Merge branch 'codex/simp-prune-tools-prompt-surface' into codex/simp-drop-assembled-section-order

# Conflicts:
#	docs/config-catalog.md
#	docs/cordis-catalog/services.md

packages/AGENTS.md

@@ -2,17 +2,16 @@
 
 These package-specific rules supplement the repo-wide [conventions](../AGENTS.md#conventions).
 
-- **Plugin export shape — namespace OR default, never both.** A *service* package exports the service class as `export default` (the Loader instantiates it). A *function/namespace* plugin exports `name` / `inject` / `Config` / `apply` as separate named exports and **must NOT add `export default`** — the cordis Loader's `unwrapExports` does `exports.default ?? exports`, so a stray default export collapses the module to the bare `apply` function and silently discards the `inject`/`name`/`Config` namespace, leaving the plugin with no injected services (it then throws `cannot get property … without inject` at load). See [docs/postmortem/0001](../docs/postmortem/0001-acp-default-export-drops-inject.md).
-- **Read an optional (non-injected) service via `ctx.get(name)`, not `ctx.<name>`.** For a service a plugin reads opportunistically but deliberately leaves out of `static inject` (e.g. `AgentLoop` reading `sessionPersistence`), the `ctx.<name>` property proxy resolves by an ancestor-only fiber walk that throws when the call arrives through a foreign traceable shadow (the service lives on a sibling fiber). `ctx.get(name)` is the topology-independent global-store lookup, strict by default (an inactive/absent backend reads as `undefined` — prefer it over the `ctx.get(name, false)` overload, which also skips the active-state check). Services that ARE in `static inject` resolve fine via `ctx.<name>`. See [docs/postmortem/0001](../docs/postmortem/0001-acp-default-export-drops-inject.md).
+- **Plugin export shape:** service packages default-export their service class; function plugins named-export `name` / `inject` / `Config` / `apply` and have no default export. Mixing the forms makes the Loader discard the function plugin's namespace ([postmortem](../docs/postmortem/0001-acp-default-export-drops-inject.md)).
+- **Optional services use `ctx.get(name)`.** Reserve `ctx.<name>` for declared injections; the property proxy is topology-sensitive, while strict `ctx.get` reads the global service store ([postmortem](../docs/postmortem/0001-acp-default-export-drops-inject.md)).
 - **A plugin shipped via `cordis.yml` needs at least one test through the REAL Loader/export path** — hand-built `ctx.plugin({...})` mounts bypass `unwrapExports` and cannot catch a broken export shape. Full testing policy (tiers, with-key generosity, real-entry-path guards): [docs/testing.md](../docs/testing.md).
 - **Typed same-process service and plugin calls are contracts, not serialization boundaries.** Prefer readonly borrowed values; materialize or defensively validate only at parser/config, queued, model/tool JSON, durable/file, worker, process, or wire boundaries.
 - **Represent one asynchronous operation with one lifecycle controller or transaction.** Separate readiness, cancellation, disposal, reservation, or sentinel state requires an independent owner or settlement boundary; otherwise fold it while preserving rollback, callback containment, and quiescence.
 
 Naming notes:
 
-- A *service* `src/index.ts` exports the service class as `export default` + all public types; a *function/namespace plugin* `src/index.ts` exports `name`/`inject`/`Config`/`apply` as named exports and NO default (the export-shape rule above).
 - `src/types.ts` contains only types — no runtime code.
 - Tests live at package level under `tests/`, not `src/__tests__/`.
-- A package's README and JSDoc are part of the change: altered behavior (config keys, defaults, error codes, wire fields) updates them in the same commit. `doc-sync` gates what it can; prose accuracy stays on the author ([the documentation standard](../docs/AGENTS.md)).
+- A package's README and JSDoc are part of the change: altered behavior (config keys, defaults, error codes, wire fields) updates them in the same commit. `doc-sync` gates what it can; apply [dsh-prose-standard](../.agents/skills/dsh-prose-standard/SKILL.md) for complete, concise prose and verify accuracy against code.
 - Package READMEs document model/token effects using the [canonical Model Experience format](../docs/cookbook/adding-a-package.md#4-write-the-package-readme).
-- Package READMEs carry `## Known Limitations and Deferred Work` or a justified [allowlist entry](../scripts/verify-package-readme-limitations.ts) ([rationale](../docs/rfc/implemented/process/2026-07-10-readme-known-limitations-gate.md)).
+- Package READMEs put durable consumer gaps and non-obvious maintainer constraints under `## Known Limitations and Deferred Work`; ordinary cleanup stays in its TODO or RFC. Packages with none use a justified [allowlist entry](../scripts/verify-package-readme-limitations.ts) ([rationale](../docs/rfc/implemented/process/2026-07-10-readme-known-limitations-gate.md)).

packages/bash/bash-local/README.md

@@ -22,7 +22,7 @@ Design surveyed against the bash tools of Claude Code, OpenCode, Codex, and pi;
 - **Spawn per call, no shell state** — every call is a fresh non-login `bash -c` (deterministic; no rc files). All four surveyed tools spawn per call. `XXX(stateful-shell)` in `src/run.ts` records the two proven stateful designs (Claude Code's cwd-only persistence; Codex's PTY exec sessions) for when real workflows demand them.
 - **Process-group kills with escalation** — children are spawned `detached` (own process group); kills send SIGTERM to the group, then SIGKILL after the `graceMs` grace (default 3s — OpenCode's escalation; pipelines and subshells die with the parent). ESRCH is tolerated; daemons that re-parent away from the group can still survive — same caveat as the surveyed tools.
 - **Tail-keep truncation + spill files** — output beyond `maxOutputBytes` keeps the in-memory TAIL (errors/results cluster at the end — pi/OpenCode rationale) while the FULL stream is appended to a temp file whose path is reported when available. If the final spill close reports a delayed writeback failure, the executor still returns the tail but withholds the path rather than advertising a possibly incomplete file.
-- **Model-friendly env + credential scrub** — `process.env` minus credential-shaped vars (`*KEY*`/`*SECRET*`/`*TOKEN*`), then `NO_COLOR=1 TERM=dumb PAGER=cat GIT_PAGER=cat` (Codex's hardcoded set) so pagers and ANSI color don't garble results. This scrub is the security control that keeps the harness's *ambient* credentials out of a spawned command. A spec's `env` is merged LAST (after the scrub), so a caller's explicit entry — a value it already holds — wins even on a credential-shaped name. The spec's `stdin`, when supplied, is written to the child and closed; with none supplied, fd 0 is `/dev/null` — the exact pre-seam default, so a command that probes stdin's file type is unaffected. Both `env`/`stdin` are set by in-process plugins (the hooks bridges); the model-facing tool doesn't expose them. See [the bash-stdin-env RFC](../../../docs/rfc/implemented/architecture/2026-06-30-bash-stdin-env-trusted-plugin-surface.md).
+- **Model-friendly environment** — ambient credential-shaped variables are removed before noninteractive terminal defaults and explicit caller entries are applied. Supplied stdin is written and closed; otherwise fd 0 is `/dev/null`. Trusted plugins use `env` and `stdin`, but the model-facing tool does not expose them. See the [bash stdin/env RFC](../../../docs/rfc/implemented/architecture/2026-06-30-bash-stdin-env-trusted-plugin-surface.md).
 - **Background tasks** — `start()` returns immediately, no timeout applies (Claude Code detaches timeouts when backgrounding), `readOutput()` is incremental with whole-stream byte offsets, and disposal kills everything. The spec's opaque `owner` token is stored on the tracked task and returned by `ownerOf(id)` — the executor never interprets it (the consumer's access policy does), and because it lives with the task here it survives a `tool-bash` HMR reload.
 
 ## Model Experience
@@ -37,6 +37,5 @@ Indirectly, through `dsh-tool-bash`, which renders this executor's bounded stdou
 - **The credential scrub is a name heuristic** — `*KEY*`/`*SECRET*`/`*TOKEN*` only; differently-named secrets (e.g. `*PASSWORD*`) pass through, and a whitelist for over-scrubbed vars is noted future work.
 - **Spill files are never deleted** — full-output recovery files (and the private per-process spill dir) accumulate under the OS tmpdir until something external cleans them.
 - **Finished background tasks are never evicted** — they stay in the task map, retaining their in-memory output tails, until executor disposal.
-- **`OutputCollector.snapshot()` / `totalBytes` are test-shaped residuals** — the live poll path uses `readFrom()` and a marked cleanup can inline the final snapshot and remove the unused public getter.
 
 The raw process handling lives in `src/run.ts`; `src/index.ts` is the service wiring.

packages/bash/bash-local/src/index.ts

@@ -1,16 +1,8 @@
 /**
- * `LocalBashExecutor`: the local-subprocess implementation of the
- * `@deepseek-ai/dsh-bash` executor seam. Spawns `bash -c` per call in its
- * own process group (see `./run.ts` for the plumbing and the agent-tool
- * survey notes), tracks background tasks, and kills everything on dispose.
- *
- * TODO(permissions/sandbox): execution policy does NOT belong here — use
- * the `tools/pre-execute` deny/ask gate (see docs/architecture.md
- * § Extending The Harness) or implement a sandboxing `BashExecutor`.
- * Reference points:
- * Claude Code wraps commands in sandbox-exec/bubblewrap; Codex applies
- * seatbelt/landlock plus an execpolicy prefix-rule engine.
- *
+ * Local-subprocess implementation of the bash seam. Each call runs in its own
+ * process group, background tasks are tracked, and disposal kills and awaits
+ * them. Execution policy belongs in `tools/pre-execute` or a sandboxing
+ * executor, not this local process layer.
  * @module @deepseek-ai/dsh-bash-local
  */
 
@@ -90,10 +82,9 @@ export class LocalBashExecutor extends BashExecutor {
     assertPositiveFinite('maxOutputBytes', this.config.maxOutputBytes)
     assertPositiveFinite('graceMs', this.config.graceMs)
     ctx.effect(() => async () => {
-      // Kill every live process group and WAIT for the processes to close so
-      // nothing outlives the fiber (HMR safety) — a TERM-trapping child is
-      // held until the SIGKILL escalation lands. The base class already
-      // silenced listeners, so these kills complete without notices.
+      // Kill every live process group and WAIT for the processes to close so nothing outlives
+      // the fiber (HMR safety) — a TERM-trapping child is held until the SIGKILL escalation
+      // lands.
       const pending: Promise<void>[] = []
       for (const task of this.tasks.values()) {
         if (task.status === 'running') {
@@ -154,23 +145,18 @@ export class LocalBashExecutor extends BashExecutor {
       stdin: spec.stdin,
       env: spec.env,
     }, this.internals).done
-    // Classify the FIRST abort reason: a BASH_TIMEOUT TimeoutReason means our
-    // timeout cut the command short; any other abort — an upstream cancel, or a
-    // foreign (outer) deadline's timeout under nesting — is aborted. Scoping to
-    // our own code keeps a nested outer deadline from reading as our timeout.
-    // Mutually exclusive by construction — the fused signal reports one cause.
+    // Classify the FIRST abort reason: a BASH_TIMEOUT TimeoutReason means our timeout cut the
+    // command short; any other abort — an upstream cancel, or a foreign (outer) deadline's
+    // timeout under nesting — is aborted.
     const timedOut = timeoutOf(d.signal, 'BASH_TIMEOUT') !== undefined
     const aborted = d.signal.aborted && !timedOut
     return { ...outcome, timedOut, aborted, timeoutMs: spec.timeoutMs }
   }
 
   start(spec: BashExecSpec): BashTask {
-    // No timeout for background tasks (matches Claude Code, which detaches
-    // the timeout when backgrounding); callers stop tasks via kill() — or
-    // via spec.signal, which the seam contract honors for background runs
-    // too (runBash wires it to the group kill). No deadline is created here,
-    // so spec.timeoutMs is ignored by design — background tasks stay
-    // timeout-free (see the timeout-library RFC).
+    // No timeout for background tasks (matches Claude Code, which detaches the timeout when
+    // backgrounding); callers stop tasks via kill() — or via spec.signal, which the seam
+    // contract honors for background runs too (runBash wires it to the group kill).
     const running = runBash({
       command: spec.command,
       cwd: spec.workdir,

packages/bash/bash-local/src/run.ts

@@ -1,23 +1,7 @@
 /**
- * Process plumbing for the local bash executor: spawn, output collection
- * with tail-keep + spill-to-disk truncation, and process-group kill with
- * SIGTERM→SIGKILL escalation.
- *
- * Everything here is deliberately free of Cordis concepts so it can be unit
- * tested in isolation; `LocalBashExecutor` owns lifecycle and configuration.
- *
- * runBash owns NO timing: it kills the process group when its `spec.signal`
- * fires and does not distinguish a timeout from a cancel. The executor fuses
- * timeout + upstream cancellation into that one signal via
- * `@deepseek-ai/dsh-timeout`'s `deadline`, and classifies the outcome from the
- * signal afterward — the timing/classification half is shared, the kill is not.
- *
- * Design notes (surveyed against Claude Code, OpenCode, Codex, and pi — see
- * the package README): spawn-per-call with `detached: true` so the child
- * leads its own process group; kills target the group (`kill(-pid)`) so
- * pipelines and subshells die with the parent. SIGTERM first, SIGKILL after a
- * grace period (OpenCode's escalation; Codex/pi jump straight to SIGKILL).
- *
+ * Process plumbing for the local bash executor: detached process-group spawn,
+ * tail-keep output with spill files, and SIGTERM→SIGKILL escalation. This layer
+ * reacts to an abort signal; the executor owns deadlines and classifies causes.
  * @module dsh-bash-local/run
  */
 
@@ -50,18 +34,9 @@ export const ENV_OVERRIDES = {
 export const SENSITIVE_ENV_PATTERN = /KEY|SECRET|TOKEN/i
 
 /**
- * `process.env` minus credential-shaped vars, plus the model-friendly
- * overrides, plus any caller-supplied `extra` entries.
+ * Build a child environment by scrubbing credential-shaped ambient variables,
+ * applying model-friendly overrides, then merging trusted caller entries last.
  *
- * Layering matters: the scrub drops `process.env` credentials, then
- * `ENV_OVERRIDES` forces the model-friendly terminal vars, then `extra` is
- * merged LAST so an explicit caller entry wins even when its name matches the
- * scrub pattern (the scrub is the control that stops the HARNESS's ambient
- * credentials leaking into a spawned command; a caller that explicitly sets a
- * var named a value it already holds, not that ambient secret). `extra` is set
- * by in-process plugins (the hooks bridges), not the model — `dsh-tool-bash`
- * builds its request from named fields only and does not forward model input
- * here (see its README, § "The tool builds its request from named args only").
  * @param extra - caller-supplied entries merged last; an explicit entry wins even against the scrub and the overrides.
  * @returns the environment to hand to `spawn` for the child process.
  */
@@ -262,10 +237,8 @@ export class OutputCollector {
       try {
         closeSync(this.spillFd)
       } catch {
-        // close can surface delayed writeback failures (for example EIO/ENOSPC)
-        // after writeSync appeared to succeed. Keep finalize total so runBash's
-        // close handler still resolves, but stop advertising a spill file that
-        // may be missing its tail.
+        // A delayed writeback failure makes the spill unreliable; keep finalize
+        // total but stop advertising that file.
         this.spillFile = undefined
       }
       this.spillFd = undefined
@@ -275,13 +248,9 @@ export class OutputCollector {
 }
 
 /**
- * Send `sig` to the process GROUP led by `pid` (requires the child to have
- * been spawned with `detached: true`). NEVER throws: kills race process exit
- * by design (ESRCH), and the other failure modes (EPERM from setuid
- * children, …) fire inside timer callbacks where a throw would crash the
- * host process — a kill that cannot be delivered is reported by the process
- * NOT dying, which callers already handle via escalation/timeouts. No-op for
- * non-positive pids (spawn never started a process).
+ * Send `sig` to a detached process group. Never throws: delivery races process
+ * exit and may run in a timer callback, so failures are contained and a
+ * non-positive pid is a no-op.
  * @param pid - the group leader's pid; non-positive means the spawn failed and the call is a no-op.
  * @param sig - the signal to deliver to the whole group.
  */
@@ -311,24 +280,13 @@ export interface RunningBash {
 }
 
 /**
- * Spawn `bash -c <command>` in its own process group and collect output.
- *
- * Outcome semantics: the returned promise REJECTS only for spawn-level
- * failures (bad cwd → ENOENT, missing binary, pre-aborted signal); every
- * runtime outcome — nonzero exit, timeout kill, abort kill, signal death —
- * RESOLVES with a {@link SpawnOutcome} describing what happened, so callers
- * shape one consistent report for the model.
- *
- * XXX(stateful-shell): per the agent-tool survey there are two proven
- * stateful designs worth revisiting — Claude Code persists ONLY cwd between
- * calls (captures `pwd -P` after each command), and Codex keeps whole PTY
- * exec sessions addressable via session ids + stdin writes. We deliberately
- * spawn a fresh non-login `bash -c` per call for determinism (no rc files,
- * no inherited shell state); revisit when real workflows demand it.
- * @param spec - the fully-resolved run (command, cwd, limits); no defaulting happens here.
- * @param internals - test-only knobs; omitted fields fall back to the private per-process spill dir.
- * @returns the live handle: pid, the two live collectors, the outcome promise, and `kill()`.
+ * Spawn one isolated `bash -c` process group and collect its output.
+ * Runtime exits resolve as {@link SpawnOutcome}; only spawn failures reject.
+ * @param spec - fully resolved command, cwd, limits, and cancellation.
+ * @param internals - test-only process and spill-directory overrides.
+ * @returns live process handle and outcome promise.
  */
+// XXX(stateful-shell): evaluate persistent cwd or PTY sessions when workflows require shell state.
 export function runBash(spec: SpawnSpec, internals: RunInternals = {}): RunningBash {
   const spillDir = internals.spillDir ?? privateSpillDir()
 
@@ -336,16 +294,7 @@ export function runBash(spec: SpawnSpec, internals: RunInternals = {}): RunningB
     throw new Error(`aborted before spawn: ${String(spec.signal.reason ?? 'aborted')}`)
   }
 
-  // stdin is a pipe ONLY when the caller supplied bytes; with none it is `ignore`
-  // (fd 0 → /dev/null) — the exact pre-seam default. This matters: a spawn pipe
-  // and /dev/null are NOT observationally identical (node's pipe is an AF_UNIX
-  // socket, so a command that probes stdin's type — `test -c /dev/stdin`, `stat
-  // /proc/self/fd/0` — sees a char device vs a socket), so the no-stdin path
-  // (every model-driven call) must keep /dev/null rather than regress to a socket.
-  // Two LITERAL `stdio` tuples (not one variable tuple): only a literal lets the
-  // typed `spawn` overload infer non-null stdout/stderr, which the
-  // `ChildProcessByStdio` annotation captures (stdin `Writable | null`; stdout/
-  // stderr the non-null `Readable` the collectors attach to without a cast).
+  // Keep absent stdin as /dev/null; literal tuples preserve non-null output types.
   const env = childEnv(spec.env)
   const child: ChildProcessByStdio<Writable | null, Readable, Readable> = spec.stdin !== undefined
     ? spawn('bash', ['-c', spec.command], { cwd: spec.cwd, env, stdio: ['pipe', 'pipe', 'pipe'], detached: true })
@@ -358,8 +307,7 @@ export function runBash(spec: SpawnSpec, internals: RunInternals = {}): RunningB
 
   let graceTimer: NodeJS.Timeout | undefined
 
-  // pid is undefined when the spawn itself fails (bad cwd, missing binary);
-  // the 'error' handler rejects `done` and kills become no-ops via pid -1.
+  // Failed spawns use pid -1 so kill remains a no-op.
   const pid = child.pid ?? -1
 
   const kill = (): void => {
@@ -368,27 +316,11 @@ export function runBash(spec: SpawnSpec, internals: RunInternals = {}): RunningB
     graceTimer = setTimeout(() => { killGroup(pid, 'SIGKILL') }, spec.graceMs)
   }
 
-  // runBash owns no timer: the executor's `run()` fuses timeout+cancel into one
-  // deadline signal (`@deepseek-ai/dsh-timeout`) and passes it here; we only
-  // listen and run the SIGTERM→grace→SIGKILL kill. Whether the abort was a
-  // timeout or an upstream cancel is classified by the executor from that
-  // signal, not tracked here.
+  // The executor owns timeout classification; this layer only reacts to abort.
   const onAbort = (): void => { kill() }
   spec.signal?.addEventListener('abort', onAbort, { once: true })
 
-  // Write stdin and close it, but ONLY when the caller supplied bytes — with no
-  // stdin, fd 0 is `ignore` (/dev/null) and `child.stdin` is null. The error
-  // handler must exist whenever we write: an unhandled 'error' on the stream
-  // would throw and crash the host. We swallow the error rather than reject
-  // `done`, and that is correct for ANY stdin-write error, not just the common
-  // one — the stdin write is BEST-EFFORT, while the command's authoritative
-  // outcome is its exit code + captured output, which the `close` handler reports
-  // regardless of whether the write landed. The expected case is EPIPE (the child
-  // exited without reading, so closing our end of a still-full pipe fails); a rare
-  // non-EPIPE pipe fault means the command ran with incomplete stdin, and it
-  // surfaces that itself through its own exit/output (e.g. a hook that gets
-  // truncated JSON errors out) — rejecting here would instead discard that real
-  // output and turn it into an opaque infrastructure error, which is worse.
+  // Stdin writes are best-effort; process exit and captured output remain authoritative.
   if (child.stdin !== null) {
     child.stdin.on('error', () => { /* stdin write is best-effort; outcome rides on exit/output. */ })
     child.stdin.end(spec.stdin)
@@ -396,8 +328,7 @@ export function runBash(spec: SpawnSpec, internals: RunInternals = {}): RunningB
 
   const done = new Promise<SpawnOutcome>((resolve, reject) => {
     child.on('error', (error) => {
-      // Spawn-level failure (ENOENT cwd, EACCES, …): no close event with
-      // meaningful output follows; clean up and reject.
+      // No meaningful close outcome follows a spawn failure.
       cleanup()
       reject(error)
     })

packages/bash/bash-local/tests/executor.spec.ts

@@ -337,7 +337,7 @@ describe('LocalBashExecutor background tasks', () => {
   })
 })
 
-describe('review fixes: lifecycle hardening', () => {
+describe('executor cancellation, callback, and disposal contracts', () => {
   it('start honors a pre-aborted or later-aborted AbortSignal', async () => {
     const { bash } = await setup()
     const controller = new AbortController()

packages/bash/bash-local/tests/run.spec.ts

@@ -189,12 +189,8 @@ describe('stdin and extra env (set by in-process plugins)', () => {
   })
 
   it('gives fd 0 the exact pre-seam type: /dev/null when no stdin, a pipe when supplied', async () => {
-    // The no-stdin path must stay observationally identical to the pre-seam
-    // `ignore` default: a command that probes stdin's file type sees a char
-    // device (/dev/null). Regressing to an always-open pipe would make fd 0 a
-    // socket (node's spawn pipe is an AF_UNIX socket, not a FIFO), flipping
-    // `test -c /dev/stdin` for every model-driven call. When bytes ARE supplied,
-    // fd 0 is that pipe (a socket), as it must be to carry them.
+    // With no bytes, fd 0 remains the pre-seam `ignore` default (/dev/null, a character device).
+    // Supplied bytes use Node's spawn pipe, which is an AF_UNIX socket rather than a FIFO.
     const none = await runBash(spec('test -c /dev/stdin && echo char || echo other')).done
     expect(none.stdout.text).toBe('char\n')
     const piped = await runBash(spec('test -S /dev/stdin && echo socket || echo other', { stdin: 'x' })).done
@@ -219,9 +215,8 @@ describe('stdin and extra env (set by in-process plugins)', () => {
   })
 
   it('does not crash or reject when the child ignores a large stdin (EPIPE)', async () => {
-    // The child exits immediately without reading; closing our end of a stdin
-    // pipe still holding ~1MiB triggers EPIPE on the write. The handler must
-    // swallow it: `done` resolves normally with the child's real exit.
+    // The child exits without reading, so closing a stdin pipe holding ~1 MiB triggers EPIPE.
+    // The handler swallows that write error and `done` reports the child's real exit.
     const big = 'x'.repeat(1024 * 1024)
     const result = await runBash(spec('exit 7', { stdin: big })).done
     expect(result.exitCode).toBe(7)
@@ -360,7 +355,7 @@ describe('abort edge cases', () => {
   })
 })
 
-describe('review fixes: env scrubbing and spill hardening', () => {
+describe('environment and spill-file hardening', () => {
   it('scrubs credential-shaped env vars from child processes', async () => {
     process.env.DSH_TEST_API_KEY = 'super-secret'
     process.env.DSH_TEST_TOKEN = 'also-secret'

packages/bash/bash-sandbox/README.md

@@ -14,7 +14,7 @@ Semantics:
 
 - **Denials are result facts.** A failed run whose stderr carries the selected backend's own denial dialect — the signatures the provider stamps on every wrap (EROFS text under bwrap, EACCES under Landlock, EPERM under Seatbelt) — is reported as `BashRunResult.sandbox.denied: true` (conservative classification, read from the collected stderr tail); every CONFINED run also carries the mode it executed under (`result.sandbox.mode`) and the provider's enforcement completeness (`result.sandbox.enforcement`: `full`, or `partial` on an older Landlock ABI).
 - **Runner failures are sandbox failures, never task failures.** A failed run matching the wrap's `runnerFailureSignatures` (the runner's own error prefix — also what the shell prints for a missing runner) means the sandbox itself broke and the command NEVER RAN; the check outranks denial classification because a runner's error text can contain denial words. The foreground path re-throws it as the structured fail-closed `SANDBOX_UNAVAILABLE` error, with the runner's first stderr line as the cause; a settled background task stamps `task.sandbox.runnerFailed` instead (no error channel remains after settle), which `bash_output` renders as its own marker.
-- **Config-time default, per-call policy.** The DEFAULT mode is fixed by this entry's config for the executor's lifetime; `resolve()` stamps it onto every spec, and an explicit request-level `sandboxMode` override — set by the tool layer only for a call whose wider mode a human granted through `ctx.approval` ([the sandbox RFC § Escalation](../../../docs/rfc/implemented/feature/2026-07-06-sandbox.md)) — makes THAT call run, classify, and report under its own mode while every neighbor keeps the default (background facts are stamped per task at settle). The capability fact `ctx.bash.sandboxMode` reports the configured default so the tool layer advertises escalation only when this executor is mounted. The model learns of the sandbox only through result facts — the static bash tool description explains the denial marker; there is no current-mode statement in the system prompt.
+- **Config default, per-call override.** `resolve()` stamps the configured sandbox mode onto each spec unless an approved request supplies a wider mode. That override affects only its call or background task. `ctx.bash.sandboxMode` reports the default so the tool advertises escalation only when supported; results report the effective mode. The model learns standing mode only from tool/result facts, not a system-prompt announcement.
 - **File effects only.** Network and process visibility are deliberately not restricted — the mode vocabulary does not pretend to cover what the backend does not enforce.
 - Process mechanics (spawn, process-group kills, output collection/spill, background tasks, credential scrub) are inherited verbatim from [`dsh-bash-local`](../bash-local/); the runner ladder, probes, and the per-platform Landlock launcher packages live with [`dsh-sandbox-local`](../../sandbox/sandbox-local/).
 
@@ -48,7 +48,7 @@ The keyless consumer-integration proofs are `tests/bwrap.e2e.ts`, `tests/landloc
 
 ### Bash tool error, indirectly
 
-**What the model sees**: If no runner can enforce a confined mode, the foreground call fails with code `SANDBOX_UNAVAILABLE` and the exact message `sandbox mode "<mode>" is requested but no sandbox backend is usable on this host; refusing to run the command unconfined. Install bubblewrap or run a Landlock-enforcing kernel (Linux), ensure sandbox-exec is usable (macOS) — Windows has no confinement backend yet — or switch the consumer to danger-full-access.` An execution-time runner failure appends ` Runner failure: <first stderr line>`.
+**What the model sees**: If no runner can enforce a confined mode, the foreground call propagates the [`SANDBOX_UNAVAILABLE` error owned by `dsh-sandbox`](../../sandbox/sandbox/README.md#confinement-error-indirectly). For an execution-time runner failure, this backend supplies the first stderr line as its detail.
 
 **Token effect**: Conditional error text is visible for that call and retained in history until compaction.
 

packages/bash/bash-sandbox/src/index.ts

@@ -1,43 +1,9 @@
 /**
- * `SandboxBashExecutor`: the sandbox-consuming implementation of the
- * `@deepseek-ai/dsh-bash` executor seam. Every spawned command is wrapped by
- * the `ctx.sandbox` provider (`@deepseek-ai/dsh-sandbox`) according to the
- * configured {@link SandboxMode}: the executor hands the provider the exact
- * `['bash', '-c', command]` argv it is about to spawn and spawns the wrapped
- * argv instead. WHICH platform runner confines it — and whether one is
- * usable at all (the provider fails CLOSED with a structured
- * `SANDBOX_UNAVAILABLE` error rather than passing the argv through) — is the
- * provider's concern (`@deepseek-ai/dsh-sandbox-local` first).
- *
- * Extends `LocalBashExecutor` so all process mechanics — spawn, process-group
- * kills, timeout escalation, output collection and spill files, background
- * tasks, the credential scrub — are the local implementation's, verbatim.
- * This package adds only the seam consumption and the result facts, which is
- * exactly the split the capability seam was designed for (a sandboxing
- * executor replaces `dsh-bash-local` without touching `dsh-tool-bash`, and
- * swapping the confinement backend never touches this package).
- *
- * A failed run whose stderr carries the selected backend's own denial
- * dialect (the signatures the provider stamps on every wrap) is classified
- * as a sandbox denial on `BashRunResult.sandbox`, and every confined result
- * also carries how completely the selected runner enforces the mode
- * (`sandbox.enforcement`, from the provider's wrap). A failure carrying the
- * backend's RUNNER-FAILURE signature instead means the sandbox itself broke
- * and the command never ran: the foreground path re-throws it as the
- * structured fail-closed `SANDBOX_UNAVAILABLE` error (late twin of the
- * provider's confine-time throw), a settled background task stamps
- * `sandbox.runnerFailed` — either way a broken sandbox can never read as a
- * failing command, and the command never slips through unconfined.
- *
- * Deny-only at the seam, escalation at the tool: a denial is a reported FACT
- * here, and the one-shot user-approved escalated retry of a denied action
- * (docs/rfc/implemented/feature/2026-07-06-sandbox.md) is driven by
- * `dsh-tool-bash` through `ctx.approval` — this executor's contribution is the
- * per-call `sandboxMode` override it honors in {@link resolve}: an escalated
- * call runs (and classifies, and reports) under ITS granted mode while every
- * neighboring call keeps its session's standing mode (or the configured
- * default when that session has no override).
- *
+ * Sandbox-consuming bash executor. It wraps the exact local bash argv through
+ * `ctx.sandbox`, inherits local process mechanics, and reports the selected
+ * mode, enforcement, and denial facts. Runner failure means the command never
+ * ran: foreground calls throw `SANDBOX_UNAVAILABLE`, while settled background
+ * tasks carry `runnerFailed`. The tool owns approval and passes per-call modes.
  * @module @deepseek-ai/dsh-bash-sandbox
  */
 
@@ -79,24 +45,11 @@ export function shellQuote(text: string): string {
 }
 
 /**
- * Conservative sandbox-denial classifier: a run counts as denied only when it
- * FAILED (nonzero exit — a signal kill is not a denial) and its stderr
- * carries one of the SELECTED BACKEND's own denial signatures — the dialect
- * the provider stamps on every wrap (`ConfinedArgv.denialSignatures`:
- * `Read-only file system` under bwrap's EROFS mounts, `Permission denied`
- * under Landlock's EACCES, `Operation not permitted` under Seatbelt's
- * EPERM). Matching the backend's dialect rather than a cross-backend union
- * keeps the classifier from claiming denials the active backend never
- * produces (bare EPERM text under a Linux runner names non-file boundaries —
- * mount, kill, ptrace — that fail the same way unsandboxed). Text inference
- * is the fallback signal until a runner provides a structured one (which
- * wins once it exists); it errs toward NOT claiming a denial, and its known
- * residual imprecision is non-sandbox text in the active dialect (an ssh
- * auth failure reads as a denial under Landlock, a refused `kill` under
- * Seatbelt).
+ * Conservatively classify a nonzero, non-signal run using only the selected
+ * backend's denial signatures. Text inference may miss a denial or match
+ * unrelated stderr in that dialect; it never uses another backend's terms.
  * @param result - the settled foreground run to classify.
- * @param signatures - the active wrap's denial dialect, case-insensitive
- *   stderr substrings.
+ * @param signatures - the active wrap's denial dialect, case-insensitive stderr substrings.
  * @returns whether the run's failure reads as a sandbox denial.
  */
 export function classifyDenial(result: BashRunResult, signatures: readonly string[]): boolean {
@@ -104,17 +57,9 @@ export function classifyDenial(result: BashRunResult, signatures: readonly strin
 }
 
 /**
- * Runner-failure classifier: a failed run whose stderr carries the SELECTED
- * BACKEND's own runner-failure signature (`ConfinedArgv.
- * runnerFailureSignatures`: the runner's error prefix, which also matches
- * the shell's runner-not-found message) means the SANDBOX itself failed and
- * the command never ran. Checked BEFORE {@link classifyDenial} — a runner's
- * error text can contain denial words (an unopenable grant root reports
- * `Permission denied`) — and surfaced as the fail-closed
- * `SANDBOX_UNAVAILABLE` error on the foreground path, `sandbox.runnerFailed`
- * on a settled background task. Same conservative-text-inference stance and
- * residual imprecision as the denial classifier (a failing task that itself
- * prints the runner's prefix reads as a runner failure).
+ * Classify a nonzero run using the selected backend's runner-failure
+ * signatures. Callers check this before denial because runner diagnostics may
+ * contain denial words; the command did not run.
  * @param result - the settled foreground run to classify.
  * @param signatures - the active wrap's runner-failure signatures,
  *   case-insensitive stderr substrings.
@@ -137,15 +82,11 @@ function matchesSignature(exitCode: number | null, stderr: string, signatures: r
 }
 
 /**
- * Sandbox-consuming bash executor. Registers as `ctx.bash` (loading it
- * INSTEAD OF `dsh-bash-local`, together with a `ctx.sandbox` provider, is
- * the whole swap — the tool layer is untouched). Its configured mode is the
- * fallback exposed by {@link sandboxMode}; `dsh-tool-bash` folds a session's
- * durable `bash/sandbox-mode` override and stamps the effective mode onto each
- * request, while an approved escalation may stamp a strictly wider mode for
- * one call. The prompt deliberately does not state the mode; each run's
- * `result.sandbox` reports what actually executed plus enforcement
- * completeness, and the tool layer renders denial or runner-failure facts.
+ * Registers as `ctx.bash` in place of the local executor and requires a
+ * `ctx.sandbox` provider; the tool layer is unchanged. The configured mode is
+ * the fallback, while a session override or approved one-shot escalation may
+ * select each call's mode. The prompt does not state the standing mode;
+ * `result.sandbox` reports the mode and enforcement actually used.
  */
 export class SandboxBashExecutor extends LocalBashExecutor {
   static inject = ['sandbox']
@@ -163,15 +104,9 @@ export class SandboxBashExecutor extends LocalBashExecutor {
   private readonly mode: SandboxMode
   private readonly workspaceRoot: string
   /**
-   * Per-task facts, keyed by task id from `start()` until the settle stamp
-   * consumes them: the mode the task runs under (per-call — an escalated task
-   * differs from its neighbors) plus its wrap facts. The seam returns facts
-   * PER WRAP — a provider may legally vary enforcement or dialect between
-   * calls — so overlapping background tasks must each classify against their
-   * OWN wrap; a single latest-wrap field would let a later `start()` clobber
-   * an earlier task's facts before it settles. A `danger-full-access` task
-   * has NO entry (nothing confined it), which is what the settle stamp keys
-   * off.
+   * Per-task mode and wrap facts retained until settlement. Overlapping tasks
+   * may use different modes or provider facts, so one latest-wrap field would
+   * misclassify earlier completions.
    */
   private readonly taskFacts = new Map<BashTaskId, {
     mode: ConfinedSandboxMode
@@ -215,11 +150,8 @@ export class SandboxBashExecutor extends LocalBashExecutor {
     }
     const confined = this.confine(spec.command, mode)
     const result = await super.run({ ...spec, command: confined.command })
-    // Runner failure outranks denial: the sandbox itself failed and the
-    // command NEVER RAN — surface the same structured fail-closed error a
-    // confine-time discovery throws (late detection, same outcome), with
-    // the runner's own first stderr line as the cause. Returning it as a
-    // task result would let a broken sandbox read as a failing command.
+    // Runner failure outranks denial because the command did not run. Throw the
+    // same fail-closed error as confine-time discovery with the first stderr line.
     if (classifyRunnerFailure(result, confined.runnerFailureSignatures)) {
       throw new SandboxUnavailableError(mode, result.stderr.text.trim().split('\n')[0])
     }
@@ -230,11 +162,8 @@ export class SandboxBashExecutor extends LocalBashExecutor {
     // Same stamped-by-resolve invariant as run().
     const mode = spec.sandboxMode as SandboxMode
     if (mode === 'danger-full-access') return super.start(spec)
-    // Sandbox facts are stamped at settle time by {@link notifyTaskDone}
-    // (denial classification runs against the settled task's collected
-    // stderr). The map entry lands synchronously after spawn, strictly
-    // before the earliest possible settle (a process exit reaches us no
-    // sooner than the next tick).
+    // Classification needs settled stderr. Store facts synchronously after
+    // spawn, before the earliest process completion can be observed.
     const confined = this.confine(spec.command, mode)
     const task = super.start({ ...spec, command: confined.command })
     const { enforcement, denialSignatures, runnerFailureSignatures } = confined
@@ -243,27 +172,16 @@ export class SandboxBashExecutor extends LocalBashExecutor {
   }
 
   /**
-   * Stamp the sandbox facts BEFORE completion listeners run: the base
-   * executor notifies from inside the task's settle path, so overriding the
-   * notification point is what makes `task.sandbox` visible to `onTaskDone`
-   * consumers and `done` awaiters alike. Each task classifies against the
-   * facts of ITS OWN wrap and reports ITS OWN mode (consumed from the
-   * per-task map here — settle is the entry's end of life): with per-call
-   * escalation, tasks under different modes settle side by side, so keying
-   * anything off the configured default would misreport them. A
-   * `danger-full-access` task has no map entry and carries no facts (nothing
-   * confined it); a signal-killed task (null exit code) is never a denial,
-   * mirroring the foreground classifier.
+   * Stamp per-task sandbox facts before completion listeners and `done` settle.
+   * Full-access tasks have no facts; signal deaths are not denials.
    */
   protected override notifyTaskDone(task: BashTask): void {
     const facts = this.taskFacts.get(task.id)
     if (facts !== undefined) {
       this.taskFacts.delete(task.id)
       const stderr = this.collectedStderr(task.id)
-      // Runner failure outranks denial (the command never ran; the runner's
-      // own error text can contain denial words). A settled task has no
-      // error channel left, so the fact IS the surface here — the foreground
-      // path throws instead.
+      // Runner failure outranks denial. Background settlement has no throw
+      // channel, so this fact is its counterpart to the foreground exception.
       const runnerFailed = matchesSignature(task.exitCode, stderr, facts.runnerFailureSignatures)
       task.sandbox = {
         mode: facts.mode,

packages/bash/bash-sandbox/tests/bwrap.e2e.ts

@@ -9,20 +9,13 @@ import { bwrapProfileArgs, LocalSandboxProvider } from '@deepseek-ai/dsh-sandbox
 import { SandboxBashExecutor } from '@deepseek-ai/dsh-bash-sandbox'
 
 /**
- * KEYLESS consumer-integration proof under bwrap: the REAL
- * `LocalSandboxProvider` (nothing forced — bwrap is the ladder's first rung,
- * so a passing probe selects it) underneath the REAL `SandboxBashExecutor`,
- * driven through the executor's public run/start paths. Verifies the WORLD
- * (files exist or don't) plus the stamped result facts — in particular that
- * bwrap's EROFS denial text classifies as `denied: true` through the
- * wrap-carried dialect; the backend-only confinement proofs live with
- * `@deepseek-ai/dsh-sandbox-local`.
+ * Keyless integration of the real provider and executor through public run/start paths. With
+ * no rung forced, a passing bwrap probe selects the ladder's first rung. The tests check world
+ * effects and stamped facts, including EROFS classification through the wrap-carried dialect;
+ * backend-only confinement is covered by `@deepseek-ai/dsh-sandbox-local`.
  *
- * Self-skips wherever the functional probe fails — no `bwrap` on PATH, or a
- * host that denies unprivileged user namespaces.
- *
- * HOME-based dirs on purpose: bwrap's `/tmp` is an ephemeral mount, so only
- * paths outside it prove the workspace-root boundary.
+ * Skips when bwrap or unprivileged user namespaces are unavailable. HOME-based paths are
+ * intentional because bwrap replaces `/tmp`, which cannot prove the workspace-root boundary.
  */
 
 const probe = spawnSync('bwrap', [...bwrapProfileArgs({ mode: 'read-only', workspaceRoot: '/' }), '--', 'true'], { timeout: 5_000, stdio: 'ignore' })

packages/bash/bash-sandbox/tests/sandbox.spec.ts

@@ -1,11 +1,8 @@
 /**
- * SandboxBashExecutor tests: the CONSUMER side of the sandbox seam. A fake
- * `ctx.sandbox` provider (injected as a real cordis service) makes wrapping,
- * policy hand-off, fail-closed propagation, classification, and fact
- * stamping all deterministic without any real runner; the real-provider
- * integration proof lives in `tests/landlock.e2e.ts`. Denials are produced
- * with plain unix permissions (a 0555 directory), which exercises the same
- * stderr signature the classifier keys on.
+ * Consumer-side `SandboxBashExecutor` tests. A fake Cordis sandbox service makes wrapping,
+ * policy hand-off, fail-closed propagation, classification, and fact stamping deterministic;
+ * real-provider integration lives in `tests/landlock.e2e.ts`. A mode-0555 directory supplies
+ * the Unix denial signature used by the classifier without requiring a real sandbox runner.
  */
 
 import { chmodSync, mkdirSync, mkdtempSync } from 'node:fs'
@@ -286,10 +283,9 @@ describe('background sandbox facts', () => {
   })
 
   it('overlapping background tasks keep their OWN wrap facts (per-task, not latest-wrap)', async () => {
-    // The seam returns facts PER WRAP — a legal provider may vary them
-    // between calls. The slow task settles AFTER the quick one started, so a
-    // latest-wrap field would classify its denial against the quick task's
-    // dialect (missing it) and stamp the wrong enforcement.
+    // Facts belong to each wrap and may vary between calls. The slow task settles after the
+    // quick task starts; a shared latest-wrap field would classify and stamp it with the wrong
+    // task's dialect and enforcement.
     const wraps: Array<Pick<ConfinedArgv, 'enforcement' | 'denialSignatures'>> = [
       { enforcement: 'partial', denialSignatures: ['permission denied'] },
       { enforcement: 'full', denialSignatures: ['read-only file system'] },

packages/bash/bash-sandbox/tests/seatbelt.e2e.ts

@@ -9,16 +9,11 @@ import { LocalSandboxProvider, seatbeltProfileArgs } from '@deepseek-ai/dsh-sand
 import { SandboxBashExecutor } from '@deepseek-ai/dsh-bash-sandbox'
 
 /**
- * KEYLESS consumer-integration proof on macOS: the REAL `LocalSandboxProvider`
- * (Linux rungs forced off, so `sandbox-exec`/Seatbelt confines) underneath
- * the REAL `SandboxBashExecutor`, driven through the executor's public
- * run/start paths. Verifies the WORLD (files exist or don't) plus the
- * stamped result facts — in particular that Seatbelt's EPERM denial text
- * classifies as `denied: true` through the wrap-carried dialect; the
- * backend-only confinement proofs live with `@deepseek-ai/dsh-sandbox-local`.
- *
- * Self-skips wherever the functional probe fails — every non-macOS host, or
- * a macOS whose `sandbox-exec` refuses the profile.
+ * Keyless macOS integration of the real provider and executor through public run/start paths.
+ * Linux rungs are forced off so Seatbelt is selected. The tests check world effects and stamped
+ * facts, including EPERM classification through the wrap-carried dialect; backend-only
+ * confinement is covered by `@deepseek-ai/dsh-sandbox-local`. Skips off macOS or when
+ * `sandbox-exec` rejects the profile.
  */
 
 const probe = spawnSync('sandbox-exec', [...seatbeltProfileArgs({ mode: 'read-only', workspaceRoot: '/' }), '--', 'true'], { timeout: 5_000, stdio: 'ignore' })

packages/bash/bash/README.md

@@ -32,7 +32,7 @@ Implementations subclass `BashExecutor`, implement the abstract methods, and cal
 
 `BashExecRequest` (command, workdir?, timeoutMs?, signal?, stdin?, env?, owner?, sandboxMode?) resolves to `BashExecSpec` (command, workdir, timeoutMs, signal?, stdin?, env?, owner, sandboxMode) before execution; `owner` and `sandboxMode` are optional on the request and **required-but-nullable** on the resolved spec, so a forgotten one is a visible `undefined` rather than a silently-absent property. `sandboxMode` is the explicit per-call sandbox-policy input: an escalation grant a human just issued ([the sandbox RFC § Escalation](../../../docs/rfc/implemented/feature/2026-07-06-sandbox.md), which outranks) or the session's standing override ([the sandbox RFC § Per-session mode switching](../../../docs/rfc/implemented/feature/2026-07-06-sandbox.md)); a sandboxing executor's `resolve()` stamps its configured default when the request carries none, and a non-sandboxing executor carries the field verbatim and confines nothing.
 
-The seam also owns the per-session mode override vocabulary (the sandbox RFC § Per-session mode switching): the log-only `'bash/sandbox-mode'` session event, the pure fold `effectiveSandboxMode(events)` (last event wins; `undefined` means "apply the executor default"), and THE write path `setSandboxMode(session, mode)` — the session log is the store, so an override survives restart by replay and two sessions can never see each other's mode. Writers must respect turn-enclosure: the ACP bridge anchors an idle switch at the next turn rather than appending between turns. The task id (`BashTaskId`) and the `owner` token (`OwnerToken`) are [branded](../../util/brand) — `OwnerToken` is a DISTINCT brand from `SessionId` (the seam never imports `dsh-session`; the `dsh-tool-bash` consumer is the single boundary that casts its `SessionId` into one). `run()` returns `BashRunResult` (exitCode, signal, timedOut, aborted, timeoutMs, stdout/stderr as `CollectedOutput`) and `start()`/`readOutput()` use `BashTask`/`BashTaskRead` for the background side. A sandboxing executor additionally stamps `sandbox` result facts on results and settled tasks (`BashSandboxInfo`: the mode it executed under, the conservative `denied` classification, and — for confined modes — the backend's `enforcement` completeness); the mode/enforcement vocabulary is owned by the [`dsh-sandbox`](../../sandbox/sandbox/) seam, and the facts are documented in [core-data-structures/bash.md](../../../docs/core-data-structures/bash.md). See `src/types.ts` for the full contracts.
+The seam owns per-session sandbox overrides through the log-only `bash/sandbox-mode` event, `effectiveSandboxMode`, and `setSandboxMode`; writers preserve turn enclosure, and replay restores the last override. `BashTaskId` and `OwnerToken` are distinct brands. Foreground `run` returns exit, timeout, cancellation, output, and optional sandbox facts; background `start` and `readOutput` use task records. A sandboxing executor reports the executed mode, conservative denial classification, and enforcement completeness. See [core-data-structures/bash.md](../../../docs/core-data-structures/bash.md) for full shapes.
 
 `stdin` and `env` are set by in-process plugins (the hooks bridges, native plugins) to feed a hook command its JSON payload on stdin and its `CLAUDE_PROJECT_DIR`/`CLAUDE_PLUGIN_ROOT` env. The model-facing `dsh-tool-bash` tool does not expose them as parameters — a model already has equivalent power through shell syntax (`FOO=bar cmd`, a heredoc), so they would be redundant tool params. This is not a security boundary: the implementation's credential scrub (not these fields) is what keeps the harness's ambient secrets out of a spawned command. They are plain optionals on the resolved spec (unlike `owner`'s required-but-nullable): a missing one means "none", the safe default. See [the bash-stdin-env RFC](../../../docs/rfc/implemented/architecture/2026-06-30-bash-stdin-env-trusted-plugin-surface.md).
 
@@ -43,5 +43,4 @@ Indirectly, through `dsh-tool-bash`, which turns executor output and sandbox fac
 ## Known Limitations and Deferred Work
 
 - **No interactive-input vocabulary** — `stdin` is written once at spawn and closed; the seam has no channel to feed a running task and no PTY session concept.
-- **Two overlapping surfaces flagged for pruning** — `BashTask.done` duplicates `onTaskDone` (shipped consumers use only the latter), and `get()`/`list()` have test-harness consumers only; both are marked in [the long-running-runtime RFC](../../../docs/rfc/proposed/architecture/2026-06-20-generic-long-running-tool-runtime.md).
 - **Foreground timeouts are always executor-owned** — a caller-owned-deadline mode on the seam is explicitly deferred by [the tool-call timeout-policy RFC](../../../docs/rfc/implemented/architecture/2026-07-07-tool-call-timeout-policy.md).

packages/bash/bash/src/index.ts

@@ -1,16 +1,6 @@
 /**
- * The bash executor seam (`ctx.bash`): an abstract service defining WHAT a
- * bash backend does — run commands, manage background tasks — without saying
- * HOW. Implementations subclass {@link BashExecutor} and register themselves
- * as the `bash` service; `@deepseek-ai/dsh-bash-local` (local subprocesses)
- * is the first. Future implementations swap in sandboxes, containers, or
- * remote exec servers without touching the tool schemas that consume them
- * (`@deepseek-ai/dsh-tool-bash`).
- *
- * The split mirrors the LLM seam (`LlmService`/`LlmAdapter`) and the
- * surveyed agents: pi hides execution behind a `BashOperations` interface
- * (local shell / SSH / VM backends), Codex behind an exec-server protocol.
- *
+ * The bash executor seam (`ctx.bash`): an abstract service defining what a bash backend does —
+ * run commands, manage background tasks — without saying how.
  * @module @deepseek-ai/dsh-bash
  */
 
@@ -39,25 +29,11 @@ declare module 'cordis' {
 }
 
 /**
- * Abstract bash execution service. Subclass, implement the abstract methods,
- * and load the subclass as a plugin — it registers as `ctx.bash` (one
- * implementation per context; loading a second throws, which is cordis'
- * standard duplicate-service behavior).
- *
- * Semantics every implementation must honor:
- * - {@link run} REJECTS only for infrastructure failures (unusable workdir,
- *   missing shell, pre-aborted signal). Nonzero exits, timeout kills, and
- *   abort kills RESOLVE with a descriptive {@link BashRunResult} — reporting
- *   a failed command is the tool layer's job, not an exception.
- * - {@link start} returns immediately; no timeout applies to background
- *   tasks (callers stop them via {@link kill} or the spec's AbortSignal).
- *   Completion must fire the {@link onTaskDone} listeners exactly once per
- *   task, and must NOT fire after the service is disposed.
- * - {@link readOutput} is incremental: consecutive reads never re-deliver
- *   output. Implementations bound their buffers; reads that lost data flag
- *   `lossy` and point at full-stream spill files when available.
- * - Disposal kills every running task and awaits their exit (no orphan
- *   processes survive `fiber.dispose()`).
+ * Registers one `ctx.bash` implementation. Runtime command failures resolve as
+ * {@link BashRunResult}; only infrastructure failures reject. Background starts
+ * return immediately without a timeout, report completion exactly once while
+ * live, and remain cancellable by signal or {@link kill}. Output reads are
+ * incremental and flag lost buffered data; disposal kills and awaits all tasks.
  */
 export abstract class BashExecutor extends Service {
   private listeners = new Set<BashTaskListener>()
@@ -74,14 +50,11 @@ export abstract class BashExecutor extends Service {
   }
 
   /**
-   * The sandbox mode this executor confines commands under BY DEFAULT, or
-   * `undefined` when it does not sandbox at all — the capability fact the
-   * tool and ACP layers read to advertise sandbox controls honestly. The
-   * getter proves a sandboxing executor is mounted and supplies its fallback
-   * mode; a session override may make the effective mode narrower or wider,
-   * so strict escalation widening is checked per call rather than encoded in
-   * this default-relative capability fact. The base class reports
-   * `undefined`; a sandboxing implementation overrides the getter.
+   * The sandbox mode this executor confines commands under BY DEFAULT, or `undefined` when it
+   * does not sandbox at all — the capability fact the tool and ACP layers read to advertise
+   * sandbox controls honestly.
+   * A session or call may override this default, so widening is evaluated per
+   * execution rather than encoded in this getter.
    * @returns the configured default mode of a sandboxing executor;
    *   `undefined` for an executor that never confines.
    */
@@ -90,12 +63,7 @@ export abstract class BashExecutor extends Service {
   }
 
   /**
-   * Resolve a caller's {@link BashExecRequest} into a fully-specified
-   * {@link BashExecSpec}, applying this implementation's config defaults and
-   * caps (working directory, default/max timeout). Consumers (tool layer)
-   * call this, then pass the result to {@link run}/{@link start} — keeping
-   * defaulting in the implementation that owns the config while the seam type
-   * stays explicit (no hidden `?? default` inside run/start).
+   * Apply implementation-owned defaults and caps to a request before execution.
    * @param request - the caller's request; omitted fields get this
    *   implementation's defaults, capped fields are clamped.
    * @returns the fully-specified spec to hand to {@link run}/{@link start}.
@@ -125,17 +93,10 @@ export abstract class BashExecutor extends Service {
   abstract get(id: BashTaskId): BashTask | undefined
 
   /**
-   * The opaque OWNER token recorded for a background task at {@link start}
-   * (from the {@link BashExecSpec}'s `owner`), or `undefined` for an unknown id
-   * OR a known-but-ownerless task. The executor stores and returns the token
-   * verbatim — it never interprets it; the access POLICY (who may read/kill a
-   * task) lives in the consumer (`@deepseek-ai/dsh-tool-bash`), which compares
-   * `ownerOf(id)` to the caller's token. Collapsing unknown-id and
-   * known-but-unowned into the same `undefined` is fine: the consumer's access
-   * gate treats `undefined` as "open", and a genuinely unknown id then fails
-   * loudly at the subsequent {@link readOutput}/{@link kill} ("unknown task").
-   * Storing ownership in the executor (disposed with ITS fiber) — not in the
-   * tool plugin — is what makes ownership survive a `tool-bash` HMR reload.
+   * The opaque OWNER token recorded for a background task at {@link start} (from the {@link
+   * BashExecSpec}'s `owner`), or `undefined` for an unknown id OR a known-but-ownerless task.
+   * The executor stores the token without interpreting policy; keeping it here
+   * lets ownership survive a consumer-plugin reload.
    * @param id - the background task id to look up ownership for.
    * @returns the token recorded at start, verbatim; undefined for an unknown
    *   id or a known-but-ownerless task.

packages/bash/bash/src/session-mode.ts

@@ -1,18 +1,9 @@
 /**
- * Per-session sandbox-mode override: the session log as the store. A runtime
- * switch (an ACP `session/set_config_option`, a test scenario) is recorded as
- * one `bash/sandbox-mode` event on the session it applies to;
- * `effective = fold(events) ?? the executor's configured default`, so an
- * override survives restart by replay, two sessions can never see each
- * other's state, and there is no external config store. The event is
- * log-only (the `approval/*` precedent): the model receives neither this event
- * nor a standing mode statement. `@deepseek-ai/dsh-tool-bash` names the mode
- * only when it renders a sandbox denial. EXECUTION honors the fold in the tool
- * layer — it stamps the effective mode onto each call's
- * `BashExecRequest.sandboxMode` (weakest-precedence: an escalation grant for
- * the call outranks it) — the executor itself stays a config-fixed default
- * plus per-call overrides.
- *
+ * Per-session sandbox-mode override stored as log-only events. Folding the log
+ * isolates sessions and survives replay; the tool stamps the override onto
+ * each call unless an approved one-shot escalation outranks it, and the
+ * executor default applies when neither exists. The model receives neither the
+ * event nor a standing-mode notice; denial results name the effective mode.
  * @module dsh-bash/session-mode
  */
 
@@ -22,11 +13,9 @@ import type { SandboxMode } from '@deepseek-ai/dsh-sandbox'
 declare module '@deepseek-ai/dsh-session' {
   interface SessionEventMap {
     /**
-     * The session's sandbox mode was switched — log-only (like `approval/*`;
-     * NOT a surface event, carries no `surfaceOp`): durable and replayable,
-     * never in the model transcript. The LAST such event is the session's
-     * override ({@link effectiveSandboxMode}); execution and ACP config-option
-     * reporting fold it without adding prompt text or a context notice.
+     * Durable log-only sandbox-mode override; never a surface event or model
+     * message. Execution and ACP option reporting fold the latest event through
+     * {@link effectiveSandboxMode} without adding a prompt notice.
      */
     'bash/sandbox-mode': { mode: SandboxMode }
   }
@@ -37,9 +26,8 @@ export const SANDBOX_MODES: readonly SandboxMode[] = ['read-only', 'workspace-wr
 
 /**
  * The session's sandbox-mode override: the last `bash/sandbox-mode` event in
- * the log, or undefined when the session never switched (callers apply the
- * executor's configured default). The pure fold — resume needs no catch-up
- * machinery because replaying the log IS the state.
+ * the log, or undefined when the session never switched and callers should use
+ * the executor default. Replay needs no separate catch-up state.
  * @param events - session events in log order (other event types are skipped).
  * @returns the mode of the last switch event, or undefined without one.
  */
@@ -52,10 +40,9 @@ export function effectiveSandboxMode(events: readonly SessionEvent[]): SandboxMo
 }
 
 /**
- * THE write path for a session's sandbox-mode override: appends exactly one
- * `bash/sandbox-mode` event — the switch IS its event; nothing mutates mode
- * state out of band. Subsequent execution and ACP config-option reporting fold
- * it on read; no prompt assembly consumes it.
+ * Append one `bash/sandbox-mode` event as the only override write path.
+ * Execution and ACP option reporting fold it on read; prompt assembly does not
+ * consume it.
  * @param session - the session the override belongs to.
  * @param mode - the mode every subsequent bash call in this session runs
  *   under (until the next switch).

packages/bash/bash/src/types.ts

@@ -71,14 +71,8 @@ export interface BashSandboxInfo {
    */
   enforcement?: SandboxEnforcement
   /**
-   * True when the executor classifies this failure as the SANDBOX RUNNER
-   * itself failing (missing binary, refused profile, fail-closed refusal
-   * before exec) — the command NEVER RAN; this is a sandbox failure, not a
-   * task failure, and it outranks `denied` (a runner's own error text can
-   * contain denial words). Only ever stamped on settled BACKGROUND tasks: a
-   * foreground run surfaces the same condition as the thrown
-   * `SANDBOX_UNAVAILABLE` error instead (the foreground path has an error
-   * channel; a settled task's facts are its only channel).
+   * The sandbox runner failed before executing the command. Set only on settled
+   * background tasks; foreground runs throw `SANDBOX_UNAVAILABLE` instead.
    */
   runnerFailed?: boolean
 }
@@ -125,17 +119,9 @@ export interface BashExecRequest {
    */
   owner?: OwnerToken | undefined
   /**
-   * Explicit per-call sandbox-policy input, overriding the executor's
-   * configured default mode for THIS call. Never a silent default: a
-   * consumer sets it only from an explicit policy source — an
-   * `'allowed-once'` grant a human just issued through `ctx.approval` (the
-   * escalation flow in the sandbox RFC § Escalation, which outranks), or the
-   * session's standing override folded from its own `bash/sandbox-mode`
-   * events (the sandbox RFC § Per-session mode switching — the user's recorded per-session
-   * choice). A sandboxing executor confines THIS call under the given mode;
-   * a non-sandboxing executor carries the field and confines nothing (the
-   * tool layer stamps neither escalation nor overrides without a sandboxing
-   * executor — see {@link BashExecutor.sandboxMode}).
+   * Explicit per-call sandbox policy. The tool stamps a session override or a
+   * one-shot approved escalation, with the grant taking precedence. Sandboxing
+   * executors honor it for this call; non-sandboxing executors do not confine.
    */
   sandboxMode?: SandboxMode | undefined
 }

packages/bash/tool-bash/README.md

@@ -22,7 +22,7 @@ The plugin also contributes the `tool:bash` prompt section (order 105) — the c
 
 `command`, `workdir`, and `timeoutMs` are resolved against the executor's config defaults via `ctx.bash.resolve()` before execution, so the executor seam (`BashExecSpec`) receives explicit `workdir`/`timeoutMs` values. The workdir default is applied in the tool layer (from the calling agent's `session.header.cwd`) BEFORE `resolve()` — the per-session cwd must come from `exec.agent`, since N sessions share one executor; only when no session cwd is available does the executor fall back to its own config / `process.cwd()`.
 
-Result text: stdout, then a `[stderr]` section, then status markers — `[sandbox: file access denied under <mode> mode]` when a sandboxing executor classified the failure as a policy denial (reported first so `[exit code: N]` stays the last line; the static description tells the model a denial is policy, not a command bug, and forbids retrying around it), `[timed out after Nms]` whenever the executor's timer fired (reported independently of how the process ended, so a command that traps SIGTERM and exits 0 still shows it), `[killed by signal: …]` for a signal death, `[exit code: N]` for a non-zero exit (reported, **not** `isError`: the model decides how to react), and `[output truncated; full output: <path>]` when the tail was kept and a safe spill file is available. If the executor knows output was dropped but cannot safely advertise a complete spill file, the path is reported as `(unavailable)`. Only infrastructure failures (spawn errors, aborts) surface as `isError` results.
+Result text contains stdout, an optional `[stderr]` section, then applicable sandbox-denial, timeout, signal, exit-code, and truncation markers. Timeout is reported independently of final exit status; nonzero exit remains a model-interpreted result rather than `isError`. Truncation links a safe complete spill file or reports it unavailable. Only infrastructure failures such as spawn errors and aborts produce `isError`.
 
 ### `bash_output`
 
@@ -34,29 +34,29 @@ Result text: stdout, then a `[stderr]` section, then status markers — `[sandbo
 
 ### Task ownership (cross-session isolation)
 
-The owning agent's session token (`session.header.id`) is stamped onto the task at spawn — passed to the executor via `resolve({ …, owner })` and stored ON THE TASK inside the executor (the `dsh-bash` `ownerOf(id)` seam), **not** in a plugin-local map. `bash_output`/`bash_kill` compare `ctx.bash.ownerOf(id)` to the caller's token (`session.header.id`) with `!== undefined` semantics and reject a task owned by a *different* session with `task <id> belongs to another session` (a task started with no agent — a non-loop caller — has no owner token and is open to anyone; a call with no `exec.agent` cannot access an owned task). Task ids are global and predictable, so under multi-session ACP this token check is the fence that stops one session's agent from reading or killing another session's background task. Because ownership lives on the task in the executor (disposed with the `dsh-bash` fiber), it **survives an independent `tool-bash` HMR reload** — closing the old plugin-local-map gap where a reload orphaned pre-reload tasks. (The `onTaskDone` listener is still effect-scoped to this plugin's `apply`, so a completion landing during the reload gap still drops its one notice — the pre-existing reload-gap drop — but the ownership fence itself is HMR-proof.)
+The executor stores the spawning session id as the task's owner. `bash_output` and `bash_kill` reject a caller with a different session id; agent-less tasks remain unowned, while agent-less calls cannot access owned tasks. Storing ownership on the task prevents predictable global ids from crossing ACP sessions and preserves the fence across tool-plugin reloads. Completion notices remain effect-scoped and may be missed during a reload gap.
 
 ## UI presentation
 
-These tools own how their calls render in a UI (an editor's tool-call card) via the `dsh-tools` `presentCall`/`presentResult` seam, each returning a `card`-tagged render intent — a UI never special-cases tool names. A FOREGROUND `bash` run declares a **terminal card**: `presentCall` returns `{ card: 'terminal', title, description?, cwd? }` — the **title** is the exact `command` ("ls -la src"), the model-written `description` rides along (rendered ABOVE the card), and `cwd` comes from the model `workdir` when given (absolute as-is, relative for the UI bridge to resolve against the session cwd; else left for the bridge to fill from the session cwd) — and `presentResult` returns `{ card: 'terminal', title?, output?, exitCode?, signal? }` carrying the raw output plus the parsed `exitCode`/`signal`, so a capable client (Zed) renders a terminal card with an exit-status pill. The result carries the raw `output`; the bridge DERIVES the ` ```console ` fenced fallback for a no-terminal-capability UI while the tool keeps model-facing result text unfenced. A `run_in_background` call is NOT a terminal (it returns a task id immediately and never streams a terminal — poll with `bash_output`) and instead returns a **generic card** (`{ card: 'generic', title, kind: 'execute', rawInput: command, content: [description] }`); an `isError` result (spawn failure / abort) likewise returns a `generic` result view with no exit pill (there is no real process exit). `bash_output`/`bash_kill` return a `generic` card with a task-scoped title ("Read output from background task bash-3" / "Kill background task bash-3") and the task id as rawInput. These methods are pure/display-only (they also run on `session/load` replay), and a malformed/older logged arg shape falls back to a generic presentation rather than throwing. See `packages/core/tools` ("Tool-owned UI presentation") and `packages/ui/acp` ("Terminal card" / "Tool-call presentation").
+UI presentation is tool-owned through `presentCall` and `presentResult`. Foreground `bash` uses a terminal card whose title is the exact command and whose optional description is separate; cwd follows an explicit `workdir`—resolved by the bridge against the session when relative—or the session cwd. Its result carries raw output plus exit or signal data, and clients without terminal support receive a bridge-derived fenced console fallback. Background runs, spawn failures, `bash_output`, and `bash_kill` use generic cards. Presenters are pure and replay-safe; malformed older arguments fall back to generic rendering. See [`dsh-tools`](../../core/tools/) and [`dsh-acp`](../../ui/acp/) for card semantics.
 
 ## Background completion notices
 
-When a background task finishes, a short notice is injected into the owning agent's session (`agent.inject()`, source `{kind: 'plugin', plugin: 'tool-bash'}`). The owning agent is found by its session token: the listener reads `ctx.bash.ownerOf(task.id)` and scans `ctx.get('agents')?.list()` for an agent whose `session.header.id` matches (read via `ctx.get` — `onTaskDone` runs on the bash fiber, a foreign fiber, so the `ctx.agents` proxy would throw). If no live agent carries that token — e.g. the owning session disconnected and its agent was disposed while the task ran on — the notice is dropped cleanly. Injection is **durable context for the next model request, not a wake-up** — an idle agent stays idle until something sends a message. That's why the tool descriptions tell the model to poll with `bash_output`.
+When a task finishes, the plugin resolves its owner token to a live agent and injects a durable completion notice. If the owner no longer exists, the notice is dropped. Injection affects the next request but does not wake an idle agent, so the model must poll with `bash_output` when it needs completion promptly.
 
 ## The tool builds its request from named args only
 
-The `BashExecRequest` seam carries optional `stdin` and `env`, used by the hooks bridges to feed a hook command its JSON payload and `CLAUDE_*` env. This tool does **not** expose them as parameters: its request is built from `command`/`workdir`/`timeoutMs`/`signal`/`owner` only, so a model that includes `env` or `stdin` keys in its tool arguments has them ignored. This is not a trust boundary — a model already has equivalent power through shell syntax (`FOO=bar cmd`, a heredoc), and the real defense against leaking the harness's ambient secrets is `dsh-bash-local`'s credential scrub, which works regardless. A regression guard drives the real tool with those extra args and asserts the resulting request carries neither field — its job is to catch a future refactor that blindly spreads `...args` into the request (which would silently forward model input into the post-scrub `env` merge), not to defend a wall. See [the bash-stdin-env RFC](../../../docs/rfc/implemented/architecture/2026-06-30-bash-stdin-env-trusted-plugin-surface.md).
+The seam supports trusted-plugin `stdin` and `env`, but the model-facing tool does not. It builds requests only from its declared arguments, signal, and owner; extra model keys are ignored. Shell syntax already provides equivalent command-level behavior, while the local executor's credential scrub protects ambient secrets. See the [stdin/env RFC](../../../docs/rfc/implemented/architecture/2026-06-30-bash-stdin-env-trusted-plugin-surface.md).
 
 ## Permissions and escalation
 
 Commands run with the executor's full authority unless a sandboxing executor ([`dsh-bash-sandbox`](../bash-sandbox/)) confines them — the deny-only sandbox reports denials as result facts, rendered here as the denial marker; per-call allow/deny/ask policy is the `tools/pre-execute` waterfall (see docs/architecture.md).
 
-On top of a denial sits the escalation gate ([the sandbox RFC § Escalation](../../../docs/rfc/implemented/feature/2026-07-06-sandbox.md)): an escalating call (`sandbox_permissions` + `justification`) resolves [`ctx.approval`](../../ui/user-approval/README.md) BEFORE anything executes — `allowed-once` stamps the granted mode onto the bash request as the seam-level `sandboxMode` override (that one call runs, classifies, and reports under the wider mode; its neighbors keep the session's effective mode), while `rejected`/`cancelled`/`unavailable` and the no-service / no-agent paths each fail closed with their own error text and execute nothing. The seam is consumed opportunistically (`ctx.get('approval')`, the dsh-tools ask-routing pattern); the grant is consumed by the very call that asked, and nothing is stored. The static description teaches — and a denied result itself prompts, via the escalation-available marker appended exactly when the fields are advertised — the SAME-TURN flow: on a denial a wider mode would cure, retry the exact command once with `sandbox_permissions` (the narrowest mode that suffices) + `justification` immediately, without detouring through chat (the approval prompt IS the user's consent); never speculatively — an escalation is grounded in a real denial (up-front only when the session already denied the same access), a prompt-stated approvals-disabled policy turns the exception off entirely, and a rejected escalation is final for that command.
+Escalating bash calls resolve `ctx.approval` before execution. `allowed-once` applies the requested mode only to that call; rejection, cancellation, unavailability, or missing approval context executes nothing and returns a distinct error. On a real denial, the model may retry the same command once in the same turn with the narrowest sufficient mode and justification; the approval prompt itself is the consent step. Escalation is never speculative, and a disabled or rejected approval is final. The [sandbox RFC](../../../docs/rfc/implemented/feature/2026-07-06-sandbox.md) owns the rationale.
 
 ## Per-session mode switching
 
-Under a sandboxing executor this plugin makes the session's standing mode override ([the sandbox RFC § Per-session mode switching](../../../docs/rfc/implemented/feature/2026-07-06-sandbox.md); the `bash/sandbox-mode` fold owned by [`dsh-bash`](../bash/README.md)) real at EXECUTION: every call is stamped `escalation grant > session override > undefined` onto `BashExecRequest.sandboxMode`; without either, the executor's `resolve()` applies its configured default. Nothing is stamped under a non-sandboxing executor (nothing would honor it) or for an agent-less caller (no session to fold). The prompt deliberately does NOT state the mode and a switch is not narrated: a standing declaration teaches the model to refuse preemptively, while the denial marker already names the mode the command ran under exactly when the boundary is hit — behavior, not belief, carries the state.
+For sandboxing executors, each call resolves mode as one-shot escalation, then session override, then executor default. Non-sandboxing and agent-less calls carry no session override. Neither the prompt nor a switch notice announces the standing mode; denial results report the effective mode when the boundary matters. See the [`dsh-bash` fold](../bash/README.md) and [sandbox switching contract](../../../docs/rfc/implemented/feature/2026-07-06-sandbox.md).
 
 ## Model Experience
 

packages/bash/tool-bash/src/index.ts

@@ -1,57 +1,10 @@
 /**
- * The model-facing bash tools: `bash`, `bash_output`, `bash_kill`. Pure
- * schema + text shaping — every process concern lives behind the `ctx.bash`
- * executor seam (`@deepseek-ai/dsh-bash`), so sandbox/permission/remote
- * executor implementations swap in without touching what the model sees.
- *
- * Background notifications: when a background task completes, a short notice
- * is injected into the owning agent's session (`agent.inject()` — the
- * documented context seam). Injection is durable context for the NEXT model
- * request, not a wake-up: an idle agent stays idle until something sends a
- * message, which is why the tool descriptions tell the model to poll with
- * `bash_output`.
- *
- * Task ownership: a background task's OWNER is an opaque token — the owning
- * agent's `session.header.id` — passed to the executor at spawn
- * (`resolve({ …, owner })`) and stored ON THE TASK inside the executor
- * (`@deepseek-ai/dsh-bash`'s `ownerOf(id)` seam), NOT in a plugin-local map.
- * `bash_output`/`bash_kill` compare `ctx.bash.ownerOf(id)` to the caller's token
- * and reject a task owned by a DIFFERENT session (`owner !== undefined && owner
- * !== caller`); an unowned task (no token — started by a non-agent caller) is
- * open to anyone. Task ids are global and predictable (`bash-1`, …); under
- * multi-session ACP (RFC 011) this token check is the fence that stops one
- * session's agent from reading or killing another session's background task.
- *
- * Storing the token on the task in the EXECUTOR (disposed with the `dsh-bash`
- * fiber), rather than in this plugin, is what makes ownership survive a
- * `tool-bash` HMR reload — a reload that reset a plugin-local map would orphan
- * a task spawned before it. (The `onTaskDone` listener is still effect-scoped
- * to this plugin's `apply`, so a
- * completion landing during the reload gap still drops its one notice — the
- * pre-existing reload-gap drop — but the ownership fence itself is HMR-proof.)
- *
- * Commands run with the executor's full authority unless a sandboxing
- * executor (`@deepseek-ai/dsh-bash-sandbox`) confines them; per-call
- * allow/deny/ask policy is the `tools/pre-execute` waterfall — see
- * docs/architecture.md § Extension And Composition. Under a sandboxing
- * executor this plugin also advertises the ESCALATION surface
- * (`sandbox_permissions`/`justification` — the sandbox RFC § Escalation,
- * docs/rfc/implemented/feature/2026-07-06-sandbox.md): a command the
- * sandbox denied may be retried once under a strictly wider mode, resolved
- * through `ctx.approval` BEFORE anything executes and failing closed on every
- * unanswerable path. The fields exist only when the mounted executor reports
- * a confining default (`ctx.bash.sandboxMode`) — a lever is never advertised
- * that the composition cannot honor.
- *
- * Per-session mode switching (the sandbox RFC § Per-session mode switching): a session may carry a
- * standing sandbox-mode override — the `bash/sandbox-mode` event fold from
- * `@deepseek-ai/dsh-bash` — which this plugin makes real at EXECUTION: each
- * call is stamped `escalation grant > session override > executor default`.
- * The prompt deliberately does NOT state the mode and no switch is narrated:
- * the model learns the boundary from the denial marker (which names the mode
- * it ran under) exactly when it matters, instead of preemptively refusing
- * work a standing declaration would discourage.
- *
+ * Model-facing `bash`, `bash_output`, and `bash_kill` tools over the executor
+ * seam. Background tasks are fenced by owning session, completion injects a
+ * durable notice, and confining executors add one-shot approval-based escalation.
+ * Notices do not wake idle agents. Ownership is stored with the executor task so
+ * it survives this plugin's reload; per-call authority is escalation grant,
+ * session override, then executor default. See the package README for the tool contract.
  * @module @deepseek-ai/dsh-tool-bash
  */
 
@@ -74,14 +27,8 @@ export const name = 'tool-bash'
 export const inject = ['tools', 'bash', 'systemPrompt']
 
 /**
- * Validate the constraints the SchemaSpec can't express. `defineTool` now
- * validates parsed args against the SchemaSpec before `execute` runs (the
- * arg-validation RFC), so type/required/enum checks are already done and `args`
- * is the validated `InferArgs` shape here. What remains are value constraints
- * the DSL has no vocabulary for: non-empty strings, a positive finite timeout,
- * and the escalation pairing (`sandbox_permissions` and `justification` travel
- * together — an approval prompt without a reason, or a reason driving nothing,
- * is a malformed ask).
+ * Validate value constraints absent from SchemaSpec: non-empty strings, a
+ * positive finite timeout, and paired escalation mode and justification.
  */
 function validateBashArgs(args: BashToolArgs): void {
   if (args.command.trim().length === 0) {
@@ -105,9 +52,7 @@ function validateBashArgs(args: BashToolArgs): void {
 }
 
 /**
- * Reject an empty `task_id`. Type and presence are guaranteed by the
- * SchemaSpec validation (the arg-validation RFC); only the non-empty constraint, which the
- * DSL can't express, is left to check here.
+ * Reject an empty `task_id`; SchemaSpec already validates type and presence.
  */
 function validateTaskId(value: string): BashTaskId {
   if (value.length === 0) {
@@ -117,10 +62,8 @@ function validateTaskId(value: string): BashTaskId {
 }
 
 /**
- * The bash tool's validated argument shape — the base parameters plus the two
- * escalation fields, which are ADVERTISED only when the mounted executor
- * reports a confining default mode (absent from the schema otherwise, so the
- * SchemaSpec validator rejects them before `execute` ever sees one).
+ * Validated bash arguments. Escalation fields are advertised only when the
+ * mounted executor reports a confining mode.
  */
 interface BashToolArgs {
   command: string
@@ -133,10 +76,8 @@ interface BashToolArgs {
 }
 
 /**
- * The strictly-wider table: what a call whose effective mode is the key may
- * escalate TO. Checked at EXECUTION, never baked into the schema — the
- * schema's enum is {@link ESCALATION_TARGETS}, because schemas are
- * registry-global while the effective mode is per-call truth.
+ * Strictly wider modes for each effective mode. Execution checks this table
+ * because the schema is global while the effective mode is per call.
  */
 const WIDER_MODES: Record<string, readonly SandboxMode[]> = {
   'read-only': ['workspace-write', 'danger-full-access'],
@@ -144,24 +85,16 @@ const WIDER_MODES: Record<string, readonly SandboxMode[]> = {
 }
 
 /**
- * The closed escalation-target vocabulary — every mode a call could ever
- * escalate TO (`read-only` is the floor; nothing escalates to it). Advertised
- * whenever the mounted executor confines: cutting the enum down to the modes
- * wider than the executor's DEFAULT would strand a session whose effective
- * mode sits below it (a `danger-full-access` default would advertise nothing
- * while a narrower-switched session stays confined with no lever).
+ * All possible escalation targets. Advertise the global set because a session
+ * override may be narrower than the executor default; execution rejects a
+ * target that is not wider for that call.
  */
 const ESCALATION_TARGETS: readonly SandboxMode[] = ['workspace-write', 'danger-full-access']
 
 /**
- * The bash tool's static description. The base text is byte-stable regardless
- * of composition (it is part of the pinned snapshot header); the escalation
- * teaching rides only when the mounted executor actually honors the fields —
- * it names the ONE sanctioned exception to the base text's "do not retry
- * another way" rule. Its deference clause ("If the session states approval
- * prompts are disabled…") points at the approval plugin's never-policy prompt
- * sentence by meaning, not by parsed wording — a rendezvous kept working by
- * that sentence continuing to open with the approvals-disabled claim.
+ * The bash tool's byte-stable base description. Escalation guidance is added
+ * only when the mounted executor can honor it, as the one exception to the
+ * ordinary no-retry guidance.
  */
 function bashDescription(escalationModes: readonly SandboxMode[]): string {
   const base = 'Execute a bash command (`bash -c`) and return its stdout/stderr. '
@@ -173,15 +106,15 @@ function bashDescription(escalationModes: readonly SandboxMode[]): string {
     + 'poll it with `bash_output` and stop it with `bash_kill`.'
   if (escalationModes.length === 0) return base
   return base + ' Attempting a command the sandbox may deny is safe and expected: run it and read the '
-    + 'marker rather than assuming the denial. When a command IS denied and a wider mode would let it '
-    + 'succeed, escalate immediately in the SAME turn — the ONE sanctioned exception to a denial: retry '
+    + 'marker rather than assuming the denial. When a command is denied and a wider mode would let it '
+    + 'succeed, escalate immediately in the same turn — the one sanctioned exception to a denial: retry '
     + 'the exact same command once with `sandbox_permissions` (the narrowest wider mode that suffices) '
     + 'plus a one-sentence `justification`. Do not detour through chat to ask permission first — the '
-    + 'approval prompt raised by that retry IS how the user consents. If the session states approval '
+    + 'approval prompt raised by that retry is how the user consents. If the session states approval '
     + 'prompts are disabled, there is no exception: a denial is final — do not set `sandbox_permissions`. '
-    + 'Never escalate speculatively: ground the request in a real denial — normally the one THIS command '
+    + 'Never escalate speculatively: ground the request in a real denial — normally the one this command '
     + 'just hit; escalating up front is fine only when this session already denied the same access. '
-    + 'A rejected escalation is final for THAT command — stop and explain, never work around '
+    + 'A rejected escalation is final for that command — stop and explain, never work around '
     + 'it — but it does not forbid attempting or escalating other commands later.'
 }
 
@@ -192,15 +125,15 @@ function streamText(output: CollectedOutput): string {
 }
 
 /**
- * Shape one finished run into the text the model sees: stdout, then a marked
- * stderr section, then exit-status markers. Non-zero exits are REPORTED, not
- * errored — the model decides how to react; only infrastructure failures
- * (spawn errors, aborts) surface as isError results.
+ * Shape one finished run into model-visible stdout, marked stderr, and status
+ * facts. Non-zero exits and sandbox denials remain ordinary results; only
+ * infrastructure failure or abort makes the tool call itself fail.
+ *
  * @param result - the completed foreground run from the executor.
- * @param escalationModes - the escalation targets this composition advertises;
- *   non-empty adds the same-turn escalation hint after a denial marker
- *   (default `[]`: no hint).
- * @returns the model-facing text: output body (or `(no output)`), then any timeout/signal/exit markers, each on its own line.
+ * @param escalationModes - the escalation targets this composition advertises; non-empty
+ *   adds the same-turn escalation hint after a denial marker (default `[]`: no hint).
+ * @returns the model-facing text: output body (or `(no output)`), then any
+ *   timeout/signal/exit markers, each on its own line.
  */
 export function renderResult(
   result: BashRunResult,
@@ -218,15 +151,12 @@ export function renderResult(
   if (body.length === 0) body = '(no output)'
 
   const markers: string[] = []
-  // The sandbox marker precedes the exit-status markers so `[exit code: N]`
-  // stays the LAST line (exitStatus() anchors its parse there). Denial is a
-  // reported fact like timeout: the model decides how to react.
+  // Keep `[exit code: N]` last so parseExitStatus() can recover it. A denial,
+  // like a timeout, remains a reported fact for the model to handle.
   if (result.sandbox?.denied) {
     markers.push(`[sandbox: file access denied under ${result.sandbox.mode} mode]`)
-    // The same-turn nudge lives at the decision point: only when this
-    // composition advertises the fields (a lever is never hinted that the
-    // schema does not offer), and inside the sandbox marker family so the
-    // exit-code marker stays the last line.
+    // Add the retry hint only when the schema advertises escalation, before
+    // the final exit marker.
     if (escalationModes.length > 0) {
       markers.push('[sandbox: escalation available — retry this exact command once with sandbox_permissions (the narrowest wider mode that suffices) + justification; the approval prompt asks the user]')
     }
@@ -247,33 +177,10 @@ export function renderResult(
   return body + markers.join('\n')
 }
 
-// ---------------------------------------------------------------------------
-// UI presentation (tool-owned). These shape how a UI (e.g. the ACP bridge)
-// renders a bash call's pending and completed states. They are display-only and
-// pure — a UI may call them during live streaming AND a session-log replay.
-// ---------------------------------------------------------------------------
+// Pure tool-owned presentation used for both live events and replay.
 
 /**
- * Pending-state presentation for a `bash` call. The TITLE is the exact `command`
- * — a `kind: 'execute'` card is rendered as a terminal whose header label IS the
- * title, and an execute-kind card HIDES `rawInput` (Zed: `should_show_raw_input
- * = !is_terminal_tool`), so the command must BE the title to be seen. This
- * mirrors the reference ACP adapters (claude-agent-acp, codex-acp), which both
- * use the bare command as an execute tool's title. The model-written
- * `description` (a readable summary) rides as a `content` text block shown ABOVE
- * the card. (Note: claude-agent-acp DROPS the description in terminal mode and
- * shows only the card; surfacing it as a content block is a deliberate
- * divergence here — we keep the human summary visible alongside the card.)
- * `rawInput` still carries the bare command for non-execute UIs that DO render it.
- *
- * `terminal` marks the call so a capable UI renders a TERMINAL card — but ONLY a
- * FOREGROUND run is a terminal: a `run_in_background` call returns a task id
- * immediately (it never streams a terminal; its output is polled via
- * `bash_output`), so it is NOT marked terminal and renders as an ordinary
- * execute card. For a foreground run the `terminal.cwd` (header) is the model
- * `workdir` when given — ABSOLUTE as-is, RELATIVE for the UI bridge to resolve
- * against the session cwd; when omitted the bridge fills the session workspace
- * cwd (this PURE presenter, args only, can't see it).
+ * Present foreground calls as terminals and background starts as generic cards.
  */
 type BashCallArgs = { command: string; description: string; workdir?: string; run_in_background?: boolean }
 
@@ -289,8 +196,7 @@ function presentBashCall(args: BashCallArgs): GenericCallView | TerminalCallView
       content: [{ type: 'text', text: args.description }],
     }
   }
-  // A foreground run IS a terminal: the command titles the card, the description
-  // renders above it, and the cwd (when the model gave a workdir) heads it.
+  // A foreground run is a terminal; an explicit workdir supplies its cwd.
   return {
     card: 'terminal',
     title: args.command,
@@ -300,26 +206,8 @@ function presentBashCall(args: BashCallArgs): GenericCallView | TerminalCallView
 }
 
 /**
- * Completed-state presentation for a `bash` call. Two parallel renderings of the
- * same output: `terminal.output` for a UI that shows a terminal card (the run's
- * stdout/stderr + status markers, exactly as the model sees them — the RAW text,
- * newlines preserved, since a terminal renderer relies on exact bytes), and a
- * fenced ```console `content` block as the fallback for a UI without terminal
- * support (the fences are a UI-only affordance, so they live here, not in the
- * model-facing result; the fenced body is trimmed of trailing blank lines for a
- * tidy block). A capable UI also gets an exit-status pill from `terminal.exitCode`
- * / `terminal.signal`, parsed from the status markers `renderResult` appended.
- *
- * Terminal output/exit is suppressed for results that are NOT a finished
- * foreground run: a `run_in_background` start (`isBackground` — the text is a
- * task-id ack, not a streamed run) and an `isError` result (a spawn failure or
- * abort — there is no real process exit to pill, and the body is an error
- * message, not `renderResult` output, so parsing it would be meaningless). Those
- * return a `generic` result whose content is the fenced ```console block. A
- * finished foreground run returns a `terminal` result carrying the RAW output
- * and the parsed exit status; the BRIDGE derives the fenced fallback from
- * `output` for a UI without terminal support, so the tool does not double-encode
- * it. A non-text result (unexpected for bash) falls through to `undefined`.
+ * Present completed foreground output as a terminal; background acknowledgements
+ * and execution errors use generic fenced output without an exit-status pill.
  */
 function presentBashResult(args: unknown, result: ToolResult): ToolResultView | undefined {
   const block = result.content.length === 1 ? result.content[0] : undefined
@@ -331,35 +219,14 @@ function presentBashResult(args: unknown, result: ToolResult): ToolResultView |
   if (isBackground || result.isError) {
     return { card: 'generic', content: [{ type: 'text', text: `\`\`\`console\n${raw.replace(/\n+$/, '')}\n\`\`\`` }] }
   }
-  // A finished foreground run: RAW output + parsed exit for the terminal card.
+  // A finished foreground run supplies raw output and parsed exit status.
   // The bridge derives the no-capability fenced fallback from `output`.
   return { card: 'terminal', output: raw, ...parseExitStatus(raw) }
 }
 
 /**
- * Recover the structured exit status from a rendered `renderResult` string — the
- * inverse of the status markers it appends. A `[killed by signal: SIG]` marker
- * yields `{signal}`; otherwise an `[exit code: N]` marker yields `{exitCode:N}`;
- * absent both we report `{exitCode:0}` (a clean run appends no marker — and a
- * trapped-timeout run that exits 0 also has none and is accurately exit 0).
- *
- * Why parse rendered text at all: `presentResult` is replay-safe and on a
- * `session/load` the ONLY thing persisted is this content text — the structured
- * `BashRunResult` is long gone — so unless the exit were added to the persisted
- * event schema (deliberately NOT done; see the terminal-rendering RFC), parsing
- * is the only channel. The match is anchored to a LEADING newline + end-of-string
- * because `renderResult` always inserts a `\n` before the marker (line ~124) onto
- * a non-empty body: a real marker is therefore always its own final line. That
- * defeats the common spoof (program output that simply ENDS in `[exit code: 5]`
- * with no trailing newline — a clean exit 0 — no longer reads as a failure).
- *
- * KNOWN RESIDUAL (inherent to the replay-only-sees-text design): a clean exit 0
- * whose body's FINAL line is itself exactly the marker text — `[exit code: N]`
- * or `[killed by signal: SIG]`, printed by the program with nothing after — is
- * still indistinguishable from a real marker and would show a wrong pill. This is
- * display-only (execution and the model-facing text are unaffected) and narrow;
- * the complete fix is to persist a structured exit on the result event, which the
- * RFC names as the escape hatch.
+ * Recover exit status from the final marked line emitted by {@link renderResult}.
+ * A program whose own final line exactly mimics a marker remains ambiguous for UI display.
  */
 function parseExitStatus(text: string): { exitCode: number } | { signal: string } {
   const signal = /\n\[killed by signal: ([^\]\n]+)\]$/.exec(text)
@@ -375,15 +242,8 @@ function presentTaskCall(verb: string, args: { task_id: string }): GenericCallVi
 }
 
 /**
- * Resolve the working directory for a bash call. Precedence: an explicit model
- * `workdir` wins; otherwise default to the calling agent's session cwd
- * (`session.header.cwd`) so each ACP session's commands run in ITS workspace,
- * not the server's launch dir. A RELATIVE model `workdir` is resolved against
- * the session cwd (the tool tells the model to pass `workdir` instead of `cd`,
- * so a relative one should be relative to the session's root, not `process.cwd()`).
- * Returns `undefined` when neither is available (no agent / headerless session /
- * no session cwd) — the executor then applies its own config/`process.cwd()`
- * default, preserving today's non-ACP behavior.
+ * Resolve an explicit workdir first, making a relative one session-cwd-relative;
+ * otherwise use the session cwd and leave executor defaulting as the fallback.
  */
 function resolveWorkdir(modelWorkdir: string | undefined, exec: { agent?: Agent }): string | undefined {
   const sessionCwd = exec.agent?.session.header.cwd
@@ -404,9 +264,7 @@ function statusLine(task: BashTask): string {
 }
 
 export function apply(ctx: Context): void {
-  // The bash tools' cross-call HABIT, which the per-tool descriptions cannot
-  // carry (they describe one call each): the exit-code marker is only useful
-  // if the model actually checks it every time.
+  // Cross-call guidance belongs in the prompt rather than one tool description.
   ctx.systemPrompt.section({
     name: 'tool:bash',
     order: 105,
@@ -414,26 +272,15 @@ export function apply(ctx: Context): void {
   })
 
   /**
-   * The caller's owner TOKEN — the owning agent's `session.header.id`, or
-   * `undefined` for a non-agent caller. Read `session.header.id` (NOT
-   * `session.id`): every other subsystem keys off the header id (the ACP bridge,
-   * both persistence backends), and the sibling `resolveWorkdir` already reads
-   * `session.header.cwd`, so using `session.id` here would be the asymmetry smell
-   * the conventions flag. The two are equal in production, but the header is the
-   * canonical identity.
+   * Return the canonical session-header id used by ACP and persistence as the
+   * task owner, or undefined for a non-agent caller.
    */
   const callerToken = (exec: { agent?: Agent }): OwnerToken | undefined =>
     exec.agent ? OwnerToken(exec.agent.session.header.id) : undefined
 
   /**
-   * Authorize a `bash_output`/`bash_kill` call against the task's stored owner
-   * token. Rejects when the task HAS an owner and it differs from the caller's
-   * token — using `!== undefined` semantics, NOT truthiness, so an empty-string
-   * token is still a real owner (never treated as unowned). An unowned task
-   * (`ownerOf` returns `undefined`) is allowed; a truly unknown id is also
-   * `undefined` here and then fails loudly at the subsequent
-   * `readOutput`/`kill` ("unknown bash task"). The conservative no-agent caller
-   * (`callerToken` undefined) cannot match an owned task and is rejected.
+   * Reject access when a task has a different session owner. Unowned tasks are
+   * allowed; unknown ids still fail in the subsequent read or kill.
    */
   const assertTaskAccess = (taskId: BashTaskId, exec: { agent?: Agent }): void => {
     const owner = ctx.bash.ownerOf(taskId)
@@ -442,15 +289,8 @@ export function apply(ctx: Context): void {
     }
   }
 
-  // Background completion → inject a notice into the owning agent's session.
-  // Find the live agent by its session id token via the agent registry, read
-  // opportunistically with `ctx.get('agents')` (NOT `ctx.agents`/static inject):
-  // this listener runs from `task.done.then` on the bash fiber — a foreign
-  // fiber — where the `ctx.agents` property proxy would throw through the
-  // traceable shadow; `ctx.get(name)` is the topology-independent lookup. No
-  // registry mounted (`undefined`) → drop the notice. Match on
-  // `agent.session.header.id`, NOT the registry key: a config agent's id differs
-  // from its session id, and the owner token IS the session id.
+  // Completion runs on the bash fiber, so use topology-independent lookup and
+  // match the executor's stored session-owner token to a live agent.
   ctx.bash.onTaskDone((task) => {
     const ownerToken = ctx.bash.ownerOf(task.id)
     if (ownerToken === undefined) return
@@ -462,62 +302,38 @@ export function apply(ctx: Context): void {
         { source: { kind: 'plugin', plugin: 'tool-bash' } },
       )
     } catch (error: unknown) {
-      // The ONE expected failure: the agent was disposed between task
-      // completion and this injection (ReactLoopAgent.inject throws
-      // `agent "<id>" is disposed`). That race is benign — drop the notice.
-      // Anything else is a real bug and must surface, not be swallowed.
+      // The one expected failure: the agent was disposed between task completion and this
+      // injection (ReactLoopAgent.inject throws `agent "<id>" is disposed`).
       if (error instanceof Error && error.message.includes('is disposed')) return
       throw error
     }
   })
 
   // The escalation surface exists whenever the mounted executor confines.
-  // Its enum is the closed target vocabulary, deliberately NOT cut down by
-  // the configured default: a session may switch to a narrower effective mode
-  // while sharing this globally registered schema. Strict widening therefore
-  // belongs to the per-call check below. An executor swap restarts this fiber
-  // (static inject) and re-registers the schema.
+  // Advertise the closed target vocabulary globally, then enforce strict
+  // widening against each call's effective session mode.
   const defaultMode = ctx.bash.sandboxMode
   const escalationModes: readonly SandboxMode[] = defaultMode === undefined ? [] : ESCALATION_TARGETS
 
   /**
-   * The session's standing mode override for an ordinary (non-escalating)
-   * call: the `bash/sandbox-mode` fold of the calling agent's log, stamped
-   * onto the request so execution follows the fold without stating it in the
-   * prompt. Weakest precedence — an escalation grant (freshly approved for
-   * exactly this call) outranks it, and without either the executor's
-   * `resolve()` applies its configured default. Undefined for a non-sandboxing
-   * executor (nothing honors it) and for agent-less callers (no session to
-   * fold).
+   * Return the calling session's folded standing mode. Approval outranks this
+   * value and the executor default applies when it is absent; non-sandboxing
+   * and agent-less calls have no override.
    */
   const sessionOverride = (exec: ToolExecution): SandboxMode | undefined =>
     defaultMode === undefined || exec.agent === undefined ? undefined : effectiveSandboxMode(exec.agent.session.events)
 
   /**
-   * Resolve a sandbox-escalation request through `ctx.approval` BEFORE
-   * anything executes. Returns the granted mode to stamp onto the bash
-   * request; throws the distinct fail-closed text for every other path (no
-   * service composed, an agent-less execution, a rejection, a cancellation,
-   * an unanswerable ask) — the registry turns the throw into this call's
-   * isError result, and nothing has run. The seam is consumed
-   * opportunistically (`ctx.get`, the dsh-tools ask-routing pattern), so a
-   * deployment without it degrades per call, never at registration.
+   * Request one-shot escalation before execution. Missing approval context,
+   * rejection, cancellation, and unavailable answers throw without running the
+   * command; the optional seam is resolved per call through `ctx.get`.
    */
   const approveEscalation = async (mode: string, justification: string, exec: ToolExecution): Promise<SandboxMode> => {
-    // Schema validation only checks ADVERTISED keys, so an unadvertised
-    // `sandbox_permissions` (no sandboxing executor) still reaches execute — reject it here so a
-    // human is never prompted to "escalate" a sandbox that is not there. When
-    // the fields ARE advertised, the registry's SchemaSpec enum has already
-    // pinned `mode` to this ladder for every caller.
+    // Reject an unadvertised escalation before prompting for a nonexistent sandbox.
     if (escalationModes.length === 0) {
       throw new Error('sandbox_permissions is not available in this composition (no sandboxing executor to escalate)')
     }
-    // Strict widening is an EXECUTION check against the call's effective
-    // mode — session override ?? executor default, the same fold ordinary
-    // calls are stamped with — deliberately not a schema constraint (the
-    // enum is the closed target vocabulary; the effective mode is per-call
-    // truth). A non-widening request fails closed here and never prompts a
-    // human.
+    // Reject sandbox widening against the call's effective mode before requesting approval.
     const effectiveMode = (sessionOverride(exec) ?? defaultMode) as SandboxMode
     if (!(WIDER_MODES[effectiveMode] ?? []).includes(mode as SandboxMode)) {
       throw new Error(`sandbox escalation to "${mode}" is not strictly wider than this call's current "${effectiveMode}" mode`)
@@ -539,8 +355,7 @@ export function apply(ctx: Context): void {
       ...exec.signal ? { signal: exec.signal } : {},
     })
     switch (outcome) {
-      // The SchemaSpec enum already pinned `mode` to the closed target
-      // vocabulary; the per-call check above proved it is strictly wider.
+      // Schema validation pins the vocabulary; the per-call check proves widening.
       case 'allowed-once': return mode as SandboxMode
       case 'rejected': throw new Error(`the user rejected escalating this command to "${mode}"`)
       case 'cancelled': throw new Error(`approval for escalating to "${mode}" was cancelled`)
@@ -580,14 +395,8 @@ export function apply(ctx: Context): void {
     },
     async execute(args: BashToolArgs, exec) {
       validateBashArgs(args)
-      // `description` is display/logging metadata only (surfaced to UIs via
-      // the tool/call session event); it is intentionally NOT forwarded to
-      // ctx.bash and has no effect on execution.
-      // An escalating call resolves approval BEFORE anything executes; every
-      // non-grant outcome throws its distinct error text and runs nothing.
-      // (validateBashArgs pinned the pairing, so the double narrow is exact.)
-      // An ordinary call carries the session's standing override instead —
-      // grant > session override > executor default (see sessionOverride).
+      // `description` is display/logging metadata only. Escalation approval
+      // completes before execution; grant > session override > executor default.
       const sandboxMode = args.sandbox_permissions !== undefined && args.justification !== undefined
         ? await approveEscalation(args.sandbox_permissions, args.justification, exec)
         : sessionOverride(exec)
@@ -603,10 +412,7 @@ export function apply(ctx: Context): void {
         ...sandboxMode !== undefined ? { sandboxMode } : {},
       }
       if (args.run_in_background === true) {
-        // Stamp the owner token (the agent's session id) onto the spec so the
-        // executor stores it on the task — the isolation fence for bash_output/
-        // bash_kill. Foreground runs pass no owner (they finish inline; nothing
-        // to fence).
+        // Store the session owner on the task for bash_output/bash_kill isolation.
         const task = ctx.bash.start(ctx.bash.resolve({ ...request, owner: callerToken(exec) }))
         return [{ type: 'text', text: `started background task ${task.id}` }]
       }
@@ -640,15 +446,11 @@ export function apply(ctx: Context): void {
       }
       text += `\n${statusLine(read.task)}`
       if (read.task.sandbox?.runnerFailed) {
-        // The sandbox RUNNER itself failed — the command never ran. The
-        // foreground path surfaces this as the structured SANDBOX_UNAVAILABLE
-        // error; a settled task's read carries the marker instead.
+        // Background settlement carries the runner-failure fact that a
+        // foreground call exposes as SANDBOX_UNAVAILABLE.
         text += `\n[sandbox: the sandbox runner itself failed under ${read.task.sandbox.mode} mode — the command did not run; this is a sandbox problem, not a command failure]`
       } else if (read.task.sandbox?.denied) {
-        // Mirrors the foreground result marker (and its same-turn escalation
-        // hint). Background denials are only classifiable once the task
-        // settles (the classifier needs the whole stderr), so the marker
-        // rides every read that sees the settled task.
+        // Mirrors the foreground result marker (and its same-turn escalation hint).
         text += `\n[sandbox: file access denied under ${read.task.sandbox.mode} mode]`
         if (escalationModes.length > 0) {
           text += '\n[sandbox: escalation available — retry this exact command once with sandbox_permissions (the narrowest wider mode that suffices) + justification; the approval prompt asks the user]'

packages/bash/tool-bash/tests/tools.spec.ts

@@ -56,12 +56,8 @@ async function setup() {
  */
 const fakeAgentDisposers = new Map<Context, (() => Promise<void> | void)[]>()
 function registerFakeAgent(ctx: Context, sessionId: string, inject: (...args: unknown[]) => void): Agent {
-  // The registry KEY (agent.id) is deliberately DIFFERENT from the session
-  // token (session.header.id) — a config agent has `agentId !== sessionId`. The
-  // owner token IS the session id, so the notice path must find the agent by
-  // `session.header.id`, NOT the registry key. Using distinct values here makes
-  // the test fail if a regression matched on the wrong field (a same-value fake
-  // would pass either way — the "hits the line but not the scenario" trap).
+  // A config agent has distinct registry (`agent.id`) and owner (`session.header.id`) tokens.
+  // Keeping them unequal makes notice lookup by the wrong field fail instead of passing by chance.
   const agent = { id: `agent-${sessionId}`, inject, session: { header: { version: 0, id: sessionId, createdAt: 0 } } } as unknown as Agent
   const dispose = ctx.agents.register(agent)
   const list = fakeAgentDisposers.get(ctx) ?? []
@@ -426,9 +422,8 @@ describe('background tools', () => {
   it('injects a completion notice into the owning agent (found via the registry by session token)', async () => {
     const ctx = await setup()
     const inject = vi.fn()
-    // The notice path looks the agent up in ctx.agents by its session token, so
-    // the agent must be REGISTERED (not merely passed to execute). Mount a
-    // registry and register a fake whose session.header.id IS the owner token.
+    // Notices look up the agent in ctx.agents by session token, so passing it to execute is not
+    // enough: the fake must be registered with a matching `session.header.id`.
     const agent = registerFakeAgent(ctx, 'bg', inject)
 
     const started = await ctx.tools.execute({
@@ -491,11 +486,8 @@ describe('background tools', () => {
   })
 
   it('drops the notice cleanly when the owning agent is gone from the registry by completion', async () => {
-    // A bash task (owned by the host-scoped bash-local fiber) can OUTLIVE its
-    // per-session agent — e.g. the ACP session disconnects and its AgentHandle
-    // disposes while the background task is still running. The owner token is
-    // still on the task, but no live agent carries it anymore, so the registry
-    // lookup finds nothing and the notice is dropped (no throw).
+    // Host-scoped bash tasks can outlive a per-session agent after an ACP disconnect. The task
+    // retains its owner token, but with no matching live agent the notice is dropped without error.
     const ctx = await setup()
     const inject = vi.fn()
     const agent = registerFakeAgent(ctx, 'bg', inject)
@@ -525,11 +517,8 @@ describe('background task ownership (cross-session isolation)', () => {
   function callAs(ctx: Context, agent: import('@deepseek-ai/dsh-agent').Agent | undefined, name: string, args: unknown) {
     return ctx.tools.execute({ callId: CallId(`own-${++callCounter}`), name, arguments: args, ...agent ? { agent } : {} })
   }
-  // Ownership is by TOKEN (session.header.id), NOT agent object identity — so
-  // each agent needs a DISTINCT session id, else every fake yields the same
-  // token and the isolation tests pass for the wrong reason (all tasks owned by
-  // the same token). The impl reads `session.header.id`, so the fakes MUST carry
-  // it.
+  // Ownership uses `session.header.id`, not object identity. Distinct ids keep the isolation tests
+  // from passing accidentally because every fake produced the same owner token.
   const fakeAgent = (sessionId: string) =>
     ({ inject: () => undefined, session: { header: { version: 0, id: sessionId, createdAt: 0 } } }) as unknown as import('@deepseek-ai/dsh-agent').Agent
 
@@ -609,11 +598,8 @@ describe('background task ownership (cross-session isolation)', () => {
   })
 
   it('ownership SURVIVES an independent tool-bash HMR reload (token lives on the executor)', async () => {
-    // The owner token lives on the TASK inside the executor (dsh-bash fiber), NOT
-    // in a tool-bash plugin-local map. So reloading ONLY tool-bash (executor +
-    // task survive) preserves ownership. This is the regression guard: a
-    // plugin-local map would make B accessible after reload, and this test would
-    // catch it.
+    // The executor task owns the token, so reloading only tool-bash preserves ownership. A
+    // plugin-local map would lose it and incorrectly expose the task to agent B.
     const ctx = new Context()
     await ctx.plugin(SystemPrompt)
     await ctx.plugin(ToolRegistry)
@@ -832,11 +818,8 @@ describe('tool-owned UI presentation (presentCall / presentResult)', () => {
   it('bash presentResult: a clean exit-0 whose output ENDS in marker-like text is NOT read as a failure', async () => {
     const ctx = await setup()
     const args = { command: 'printf "[exit code: 5]"', description: 'print' }
-    // A successful command can print text that looks like a marker. renderResult
-    // for a clean exit 0 appends NOTHING (and no trailing newline), so the body's
-    // own tail is `[exit code: 5]`. The parse requires a LEADING newline before
-    // the marker (renderResult always inserts one before a REAL marker), so this
-    // no-trailing-newline body is NOT mistaken for a failure → exitCode 0.
+    // A successful command may print marker-like text. A clean result appends no marker or
+    // newline; parsing requires the leading newline emitted for real markers, so this stays exit 0.
     const out = ctx.tools.get('bash')!.presentResult!(args, { content: [{ type: 'text', text: '[exit code: 5]' }], isError: false })
     expect(out).toEqual({ card: 'terminal', output: '[exit code: 5]', exitCode: 0 })
     // Same for a fake signal marker with no leading newline.
@@ -899,26 +882,18 @@ describe('tool-owned UI presentation (presentCall / presentResult)', () => {
 
   it('presentCall validates softly: malformed args (missing required description) return undefined, never throw', async () => {
     const ctx = await setup()
-    // defineTool wraps presentCall to soft-validate against the schema and fall
-    // back to undefined (a generic UI presentation) rather than throwing on the
-    // display path — it may run on replay of arbitrary logged args. The
-    // ToolDefinition.presentCall takes `unknown`, so a malformed shape needs no cast.
+    // `defineTool` soft-validates replayed logged args before presentation. Invalid shapes return
+    // undefined for generic UI rendering rather than throwing; `presentCall` accepts `unknown`.
     expect(ctx.tools.get('bash')?.presentCall?.({ command: 'ls' })).toBeUndefined()
   })
 })
 
 describe('the model-facing bash tool builds its request from named args only (no {...args} forward)', () => {
   /**
-   * Records every {@link BashExecRequest} the consumer hands to `resolve()`, so a
-   * test can assert what the model-facing tool DID and DID NOT forward. The `bash`
-   * tool does not expose `stdin`/`env` as parameters (bash syntax already gives a
-   * model that power), so it must build its request from named args only and
-   * never spread unknown tool-call keys into it. This guard's job is to catch a
-   * future refactor that blindly forwards `...args` — which would silently thread
-   * model input into the post-scrub `env` merge — NOT to defend a trust boundary
-   * (the credential scrub in dsh-bash-local is the security control; see the
-   * bash-stdin-env RFC). Foreground `run()` returns a canned result; `start()` is
-   * unused here.
+   * Records requests passed to `resolve()` so tests can prove the model-facing tool forwards only
+   * named arguments. It intentionally exposes neither `stdin` nor `env`; this catches a future
+   * `...args` spread into the post-scrub env merge. The credential scrub remains the security
+   * boundary; see the bash stdin/env RFC. Foreground `run()` is canned and `start()` is unused.
    */
   class RecordingBashExecutor extends BashExecutor {
     readonly requests: BashExecRequest[] = []
@@ -961,12 +936,9 @@ describe('the model-facing bash tool builds its request from named args only (no
 
   it('does not forward env/stdin even when the model includes them as extra arguments', async () => {
     const { ctx, bash } = await setupRecording()
-    // Extra args: the model includes `env` and `stdin` keys hoping they reach the
-    // executor. The bash tool's schema ignores unknown keys, and execute() builds
-    // the request from only command/workdir/timeoutMs/signal — so the recorded
-    // request carries NEITHER. (Not a security wall — the model could set an env
-    // var or feed stdin via shell syntax anyway; this just keeps the request
-    // shape honest so a future `...args` spread can't silently forward input.)
+    // Unknown `env` and `stdin` keys are ignored by the schema and named request construction.
+    // This preserves the request shape; it is not a security boundary because shell syntax can
+    // already set environment variables or feed stdin.
     await ctx.tools.execute({
       callId: CallId('no-forward-1'),
       name: 'bash',
@@ -1446,11 +1418,9 @@ describe('per-session sandbox mode (the bash/sandbox-mode fold)', () => {
   })
 
   it('escalates relative to the session effective mode, not the executor default (narrower override)', async () => {
-    // The blocker scenario: a workspace-write default with a read-only
-    // override — the sensible escalation is workspace-write, which a
-    // default-relative ladder could not even express. The static target
-    // vocabulary advertises it and the execution check accepts it as
-    // strictly wider than the CALL's effective (overridden) mode.
+    // With a workspace-write default and read-only override, escalation must return to
+    // workspace-write. The static target vocabulary exposes it, and validation compares it with
+    // the call's effective override rather than a default-relative ladder.
     const ctx = await setupModal('workspace-write', { approval: true })
     ctx.on('approval/request', () => Promise.resolve<ApprovalOutcome>('allowed-once'))
     const seen: (string | undefined)[] = []

packages/code-runtime/code-runtime-worker/README.md

@@ -29,11 +29,11 @@ Every field is validated (positive numbers) and defaulted; there are no other tu
 
 ## The worker entry, unbuilt and built
 
-`worker.ts` is deliberately erasable-only TypeScript with type-only cross-package imports: unbuilt (vitest/tsx), the host spawns `src/worker.ts` directly and Node's native type stripping loads it; built, the entry ships as the sibling CommonJS bundle `lib/worker.cjs` (its own tsdown entry). The CommonJS format is required because pkg's VFS Worker hook compiles filesystem-string entries as CommonJS. The host converts either entry URL to a filesystem string before constructing `Worker`, which works through both ordinary Node resolution and that pkg hook. The built path is pinned by `tests/built-lib.e2e.ts`, the real-load-path guard from [docs/testing.md](../../../docs/testing.md).
+Source mode loads erasable-only `src/worker.ts` through Node's native type stripping. Built mode passes the sibling `lib/worker.cjs` as a filesystem path because pkg's VFS Worker hook expects CommonJS; the same path works under ordinary Node. `tests/built-lib.e2e.ts` pins the real load path required by [docs/testing.md](../../../docs/testing.md).
 
 ## Model Experience
 
-Indirectly, through Code Mode in `dsh-tools`, which renders this worker's capped printed or returned data, exact `[dsh-code-runtime-worker] log capture truncated at <maxLogBytes> bytes` and `… [truncated]` markers, and `Error: code run failed (<kind>): <message>` failures into a retained `run_code` result while keeping binding traffic and worker internals outside context.
+Indirectly, through Code Mode in [`dsh-tools`](../../core/tools/README.md), which renders this worker's capped printed or returned data and exact `[dsh-code-runtime-worker] log capture truncated at <maxLogBytes> bytes` and `… [truncated]` markers into a retained `run_code` result. Binding traffic and worker internals stay outside context.
 
 ## Known Limitations and Deferred Work
 

packages/code-runtime/code-runtime-worker/src/bootstrap.ts

@@ -1,12 +1,7 @@
 /**
- * Worker-side execution logic, written as plain functions over an injected
- * port so the unit suite can run every line IN-PROCESS against a fake port
- * (a real worker thread is a separate V8 isolate the coverage provider
- * cannot observe). The real worker entry (`worker.ts`) is a thin
- * self-executing glue file over {@link runWorkerMain}, excluded from
- * coverage the same way `bin.ts` entrypoints are, and exercised end-to-end
- * by the integration tests that spawn real workers.
- *
+ * Worker-side execution logic, written as plain functions over an injected port so the unit
+ * suite can run every line IN-PROCESS against a fake port (a real worker thread is a separate
+ * V8 isolate the coverage provider cannot observe).
  * @module @deepseek-ai/dsh-code-runtime-worker/src/bootstrap
  */
 
@@ -96,12 +91,11 @@ export function makeConsoleShim(logs: LogBuffer): Record<(typeof CONSOLE_LEVELS)
 
 /**
  * Redirect a stream's `write` into the log buffer (the program-visible
- * `process.stdout`/`process.stderr` in the real worker), so raw writes land
- * in emission order alongside console output instead of racing down a pipe.
- * The shim keeps Node's `write(chunk[, encoding][, callback])` contract: the
- * callback fires asynchronously once the chunk is admitted (a program
- * awaiting flush completion must complete, not sit until the wall timeout),
- * even for writes the exhausted budget drops.
+ * `process.stdout`/`process.stderr` in the real worker), so raw writes land in emission order
+ * alongside console output instead of racing down a pipe. It preserves Node's optional callback
+ * contract: the callback runs asynchronously after admission, even when the log budget drops
+ * the write.
+ *
  * @param logs - the buffer captured writes are pushed into.
  * @param stream - the stream whose `write` slot is patched.
  * @param source - the log source the captured writes are attributed to.
@@ -152,16 +146,12 @@ export function truncateUtf8Bytes(text: string, maxBytes: number): string {
 }
 
 /**
- * Prepare the program's completion value for the done message: a value whose
- * MEASURED cross-boundary size fits `maxValueBytes` crosses raw — exact
- * bytes for a string, the structured-clone wire size (`v8.serialize`) for
- * everything else, so a huge container whose BOUNDED inspect rendering
- * happens to be small cannot smuggle itself past the cap. Anything else
- * (non-cloneable, or oversized) is REPLACED by its bounded `util.inspect`
- * rendering, byte-truncated ({@link truncateUtf8Bytes}) with an in-band
- * marker — the seam contract's "a non-transferable value is replaced by a
- * string rendering", extended to oversized ones so a huge return cannot
- * flood the host.
+ * Prepare the program's completion value for the done message: a value whose MEASURED
+ * cross-boundary size fits `maxValueBytes` crosses raw — exact bytes for a string, the
+ * structured-clone wire size (`v8.serialize`) for everything else, so a huge container whose
+ * bounded inspect rendering happens to be small cannot smuggle itself past the cap. Oversized
+ * or non-cloneable values are replaced by a bounded string rendering with an in-band marker.
+ *
  * @param value - the program's completion value.
  * @param maxValueBytes - the byte cap for the value.
  * @returns the done-message fragment: `{}` for `undefined`, else `{ value }`.
@@ -215,13 +205,11 @@ export function wireReplies(port: BootstrapPort, pending: Map<number, PendingCal
 }
 
 /**
- * Build the binding namespace objects the program sees: one null-prototype
- * global per namespace, each declared name an own enumerable async function
- * that bridges over the port (`__proto__`/`constructor`/`toString` are
- * ordinary keys, never prototype collisions). A non-cloneable argument
- * rejects that one call with a descriptive error; the host's reply (`ok`
- * false) rejects it likewise, so a failed tool call surfaces in the program
- * as an ordinary promise rejection.
+ * Build the binding namespace objects the program sees: one null-prototype global per
+ * namespace, each declared name an own enumerable async function that bridges over the port
+ * (`__proto__`/`constructor`/`toString` are ordinary keys, never prototype collisions).
+ * Non-cloneable arguments and host failure replies reject only the corresponding call.
+ *
  * @param data - the boot payload's namespace declarations (globals + names).
  * @param port - the port binding calls are posted to.
  * @param pending - the id-keyed map each posted call parks its handles in.
@@ -256,17 +244,12 @@ export function makeNamespaces(
 }
 
 /**
- * Run one program to settlement and post the {@link DoneMessage}: wires the
- * reply handler, materializes the namespaces and console shim, compiles the
- * type-stripped body as an async function (top-level `await`/`return`
- * work), and reports a thrown program error as the done message's `error`
- * field. Exactly one done message is ever posted.
- * @param port - the message port to the host (the real `parentPort`, or the tests' fake).
+ * Run one strict async-function body, allowing top-level `await` and `return`, and post exactly
+ * one terminal {@link DoneMessage}; a thrown program error becomes its `error` field.
+ * @param port - host message port or test double.
  * @param data - the boot payload the host sent.
- * @param streams - the stream objects whose `write` is captured (the real
- *   `process.stdout`/`process.stderr` in the worker; fakes in tests).
- * @returns resolves after the done message is posted (the tests await it;
- *   the real entry lets the worker exit naturally).
+ * @param streams - stdout/stderr objects captured as program logs.
+ * @returns after posting the done message.
  */
 export async function runWorkerMain(
   port: BootstrapPort,

packages/code-runtime/code-runtime-worker/src/index.ts

@@ -1,14 +1,8 @@
 /**
- * Worker-thread implementation of the code-execution seam: one fresh Node
- * worker per run, executing the model's TypeScript after a host-side
- * type-strip, with bindings bridged over the message port. Containment, not
- * a security boundary (bash-equivalent trust — see the Code Mode RFC's
- * trust-posture section): the worker gets an EMPTY environment, a heap cap,
- * and two independent budgets — `computeMs` metered on the worker's
- * measured event-loop busy time (a hot loop cannot hide behind a pending
- * binding call) and a never-pausing `maxWallMs` ceiling — all funneling
- * into `worker.terminate()`, which ends hot synchronous loops too.
- *
+ * Worker-thread code runtime: a fresh worker runs each host-type-stripped TypeScript program
+ * and bridges bindings over its message port. This is containment, not a security boundary:
+ * model code has bash-equivalent trust despite an empty environment, a heap cap, measured
+ * event-loop busy-time and wall-time budgets, and termination that also stops synchronous loops.
  * @module @deepseek-ai/dsh-code-runtime-worker
  */
 
@@ -282,11 +276,9 @@ export class WorkerCodeRuntime extends CodeRuntime {
       // Model code gets NO ambient environment — stronger than the scrubbed
       // env the defensive-patterns rule requires for spawned commands.
       env: {},
-      // Hermetic flags too: without this the worker inherits the host
-      // process's execArgv (a test runner's or tsx's loader hooks), which a
-      // bare isolate with an empty environment cannot satisfy. The entry
-      // needs nothing beyond native type stripping, on this repo's whole
-      // Node range.
+      // Hermetic flags too: without this the worker inherits the host process's execArgv (a
+      // test runner's or tsx's loader hooks), which a bare isolate with an empty environment
+      // cannot satisfy.
       execArgv: [],
       resourceLimits: { maxOldGenerationSizeMb: this.config.maxOldGenerationSizeMb },
       // Backstop capture: the bootstrap patches JS-level writes into its own
@@ -302,12 +294,8 @@ export class WorkerCodeRuntime extends CodeRuntime {
       const logs: CodeLogEntry[] = []
       const strayLogs: CodeLogEntry[] = []
 
-      // ONE host-side ledger for everything that lands in `logs`/`strayLogs`,
-      // whatever the path: honest port entries, FORGED port entries (model
-      // code posting `log` messages directly, bypassing the worker-side
-      // LogBuffer), and stray pipe bytes. On the first overflow it emits the
-      // same in-band marker the worker's LogBuffer would and drops the rest,
-      // so the documented cap is one shared `maxLogBytes` however it is hit.
+      // One host-side budget covers normal, forged, and stray-pipe log entries. The first
+      // overflow emits the shared in-band marker and drops everything after it.
       let logBudget = this.config.maxLogBytes
       let logsTruncated = false
       const admit = (entry: CodeLogEntry, sink: CodeLogEntry[]): void => {
@@ -331,11 +319,8 @@ export class WorkerCodeRuntime extends CodeRuntime {
       worker.stdout.on('data', captureStray('stdout'))
       worker.stderr.on('data', captureStray('stderr'))
 
-      // Settlement: exactly one outcome wins; every path funnels through
-      // here, cleans up the timers/listeners, terminates the worker, and
-      // resolves only after the worker actually exited (quiescence). Logs
-      // streamed eagerly before the settlement are kept — a timed-out or
-      // killed program still shows the model what it printed.
+      // Exactly one outcome wins. Every path cleans up, terminates, and awaits the worker;
+      // logs captured before timeout, abort, or failure remain in the result.
       let finishResolve!: () => void
       const finished = new Promise<void>((done) => { finishResolve = done })
       const finish = (result: Omit<CodeRunResult, 'logs'>): void => {
@@ -353,11 +338,8 @@ export class WorkerCodeRuntime extends CodeRuntime {
 
       const onDone = (message: WorkerToHost): void => {
         if (message.type !== 'done') return
-        // Re-cap the completion value HOST-side: the honest path already
-        // capped it in the worker (prepareValue there), but a forged done
-        // message bypasses the bootstrap entirely — without this, model code
-        // could flood the host past maxValueBytes. Honest values pass
-        // unchanged (see VALUE_RENDER_SLACK); the error text is bounded too.
+        // Re-cap forged completion traffic at the hostile boundary. Honest worker-capped values
+        // pass unchanged via VALUE_RENDER_SLACK; error text is bounded too.
         finish({
           ...prepareValue(message.value, this.config.maxValueBytes + VALUE_RENDER_SLACK),
           ...message.error ? { error: { kind: 'exception' as const, message: truncateUtf8Bytes(message.error.message, this.config.maxValueBytes) } } : {},

packages/code-runtime/code-runtime-worker/src/protocol.ts

@@ -1,11 +1,7 @@
 /**
- * Wire protocol between the host runtime and the worker bootstrap. Everything
- * crossing the message port is structured-clone-plain and versionless — both
- * ends ship in this package, always at the same version. The host treats
- * inbound traffic as HOSTILE (the worker runs model code, which can reach
- * `parentPort` via `import('node:worker_threads')` and forge any of these
- * shapes); the worker treats inbound traffic as trusted.
- *
+ * Versionless, structured-clone wire protocol between co-shipped host and worker code. The host
+ * treats inbound traffic as hostile because model code can forge `parentPort` messages; the
+ * worker trusts host replies.
  * @module @deepseek-ai/dsh-code-runtime-worker/src/protocol
  */
 

packages/code-runtime/code-runtime-worker/src/worker.ts

@@ -1,12 +1,6 @@
 /**
- * The worker-thread entrypoint: self-executing glue over
- * `bootstrap.ts`'s {@link runWorkerMain}, kept to the spawn wiring alone.
- * Like `bin.ts` CLI entrypoints, this file executes only inside a spawned
- * worker isolate — a place the coverage provider cannot observe — so it is
- * excluded from the coverage gate while every line of actual logic lives in
- * `bootstrap.ts`, unit-tested in-process; the real spawn path is pinned by
- * the integration tests that run genuine workers.
- *
+ * Spawn-only worker entrypoint over {@link runWorkerMain}. Executable logic stays in
+ * `bootstrap.ts` for in-process coverage; real-worker tests cover this glue.
  * @module @deepseek-ai/dsh-code-runtime-worker/src/worker
  */
 

packages/code-runtime/code-runtime-worker/tests/built-lib.e2e.ts

@@ -5,19 +5,10 @@ import { fileURLToPath } from 'node:url'
 import { describe, expect, it } from 'vitest'
 
 /**
- * BUILT-ARTIFACT smoke for the published package (the real-load-path guard
- * from docs/testing.md): the unit suite runs `src/` under vitest, where the
- * worker entry resolves to `src/worker.ts` — a consumer runs `lib/index.js`
- * under plain `node`, where it must resolve the sibling `lib/worker.cjs`
- * bundle instead. This spawns plain `node` (NOT tsx) from inside the package
- * directory and imports the package BY NAME, so resolution flows through the
- * real `exports` map exactly as it would from a downstream install; the
- * program exercises the type-strip, the worker spawn, the binding bridge,
- * and log capture end-to-end through the built bundles.
- *
- * It build-gates: SKIPS when the built artifacts are absent (suite run
- * without `pnpm run build`); CI runs it after the build step. KEYLESS — no
- * model is involved.
+ * Keyless built-artifact smoke: plain Node imports the package by name through its exports map,
+ * then exercises type stripping, sibling `worker.cjs` loading, bindings, and logs. Unit tests use
+ * `src/worker.ts`; this pins the downstream `lib/index.js` path. It skips when `lib/` is absent,
+ * and CI runs it after the build.
  */
 
 const pkgDir = fileURLToPath(new URL('..', import.meta.url))

packages/code-runtime/code-runtime-worker/tests/runtime.spec.ts

@@ -255,10 +255,8 @@ describe('WorkerCodeRuntime — budgets and containment (real workers)', () => {
   it('captures pipe writes that bypass the patched write slot as stray logs, capped by the same budget', async () => {
     const { runtime } = await setup({ maxLogBytes: 4 })
     const result = await runtime.run({
-      // The bootstrap patches the stream instance's own `write`; going
-      // through the prototype's slot reaches the real pipe underneath, so
-      // the bytes arrive host-side as stray data. The pauses keep the two
-      // writes in separate pipe chunks and let them land before settlement.
+      // The prototype write bypasses the patched instance and reaches the real pipe. Pauses keep
+      // writes in separate chunks and let both reach the host before settlement.
       program: `
         const write = (text) => Object.getPrototypeOf(process.stdout).write.call(process.stdout, text);
         write('abcd');

packages/code-runtime/code-runtime-worker/tsdown.config.ts

@@ -1,17 +1,9 @@
 import { defineConfig } from 'tsdown'
 
 /**
- * Package-shape override (see the root tsdown.config.ts): besides the
- * default lib/index.js bundle, the worker BOOTSTRAP ships as its own
- * sibling CommonJS entry — `new Worker(fileURLToPath(new URL('./worker.cjs', import.meta.url)))`
- * loads it as a file, so it cannot be part of the index bundle. pkg's VFS
- * Worker hook compiles string-path entries as CommonJS, so an ESM worker is
- * not viable inside the executable. TWO
- * single-entry builds, not one two-entry build: a multi-entry build emits
- * the shared bootstrap module as a `lib/bootstrap-*.js` chunk both bundles
- * import, which the package.json `files` whitelist (deliberately exact)
- * would omit from the packed artifact — each single-entry build inlines its
- * own bootstrap copy instead, keeping every shipped file self-contained.
+ * Build the index and worker as separate single-entry bundles. The sibling `worker.cjs` is loaded
+ * by file and must be CommonJS for pkg's VFS Worker hook. A multi-entry build emits an unlisted
+ * shared chunk omitted by the package's exact `files` whitelist; separate builds inline it.
  */
 export default defineConfig([
   {

packages/code-runtime/code-runtime/src/index.ts

@@ -1,18 +1,6 @@
 /**
- * The code-execution seam (`ctx.codeRuntime`): an abstract service defining
- * WHAT a code runtime does — run one model-written program against a set of
- * host-provided async bindings and report `{ value, logs, error? }` — without
- * saying HOW. Implementations subclass {@link CodeRuntime} and register
- * themselves as the `codeRuntime` service; backends may differ by execution
- * substrate (worker thread, separate process, container) and by source
- * language, both declared as readonly descriptors. The design and its
- * consumer (the tool registry's Code Mode) are specified in the Code Mode RFC
- * (docs/rfc/implemented/feature/2026-06-15-code-mode.md).
- *
- * The split mirrors the bash seam (`BashExecutor`): the runtime knows nothing
- * about tools or sessions — it is handed named async functions and a program,
- * and everything tool-shaped stays with the consumer.
- *
+ * Code-execution seam for running one model-written program against host async bindings.
+ * Runtimes know nothing about tools or sessions; consumers own those concerns.
  * @module @deepseek-ai/dsh-code-runtime
  */
 
@@ -35,26 +23,10 @@ declare module 'cordis' {
 }
 
 /**
- * Abstract code-execution service. Subclass, implement {@link run} and the
- * two descriptors, and load the subclass as a plugin — it registers as
- * `ctx.codeRuntime` (one implementation per context; loading a second throws,
- * cordis' standard duplicate-service behavior).
- *
- * Semantics every implementation must honor:
- * - {@link run} resolves with an error FIELD for every program outcome —
- *   parse/transform failures, thrown exceptions, budget expiry, abort,
- *   substrate death ({@link CodeRunFailure}'s taxonomy). It REJECTS only for
- *   caller misuse of the seam itself (e.g. a run submitted after disposal).
- * - Binding calls bridge to the caller's {@link CodeBindingFunction}s
- *   verbatim; arguments and resolutions must be structured-cloneable, and the
- *   runtime treats the program as a hostile peer (arbitrary binding names are
- *   own properties, malformed traffic is rejected or ignored, never crashes
- *   the host).
- * - Runs are isolated from each other: no state survives from one run to the
- *   next through the runtime.
- * - Disposal reaches quiescence: in-flight runs are terminated AND awaited
- *   before the service's own teardown completes (no orphan substrate survives
- *   `fiber.dispose()`).
+ * Registers one `ctx.codeRuntime` implementation. Program, budget, abort, and substrate
+ * failures resolve in {@link CodeRunResult}; only seam misuse rejects. Implementations bridge
+ * structured-cloneable bindings while treating programs as hostile peers, isolate runs from
+ * one another, and terminate and await in-flight runs during disposal.
  */
 export abstract class CodeRuntime extends Service {
   /**

packages/compact/compact-basic/README.md

@@ -6,16 +6,15 @@ This is the implementation tier of the compaction capability — see the [interf
 
 ## What it owns
 
-The abstract contract states only WHAT compaction does; this backend owns every HOW decision:
+This backend owns the compaction policy:
 
-- **Token estimation** — `estimateContentTokens()`: chars divided by the `charsPerToken` config (default 4) with per-block structural overhead (`text`/`reasoning` = `ceil(len/charsPerToken) + 4`, `tool-call` from name + arguments, `tool-result` recursive, unknown blocks via JSON length). The pressure gate estimates the NEXT request via `estimatePressure()`: the session prefix (the `agent/session-prefix` product — composed by the loop BEFORE the pre-step seam and handed through it, so the gate counts the prefix this instance will actually send in front of the history, never a stale logged one) + the derived history + the system prompt.
-- **Retention policy** — `compactIfNeeded()` walks the surface nodes tail→head summing per-node token estimates, and retains the smallest tail-run of WHOLE units (a closed step, or a single no-step node such as a pre-step `user/message` or inter-step `steering/message`) whose total reaches `retainTokens`; everything older is compacted. Retention is **turn-agnostic** — turn boundaries play no role, so a single runaway turn that alone exceeds the window compacts its OWN early closed steps rather than being retained verbatim (the failure mode that motivated dropping turn-protection: a tool-heavy turn must stay compactable or the harness dies exactly when compaction is needed). The only structural guard is **tool-pairing balance**: the compacted region's edges are balanced cuts on the surface (no unanswered tool-call crosses either edge), so it never splits a step's `assistant/message` tool-calls from their `tool/result`s. When the only compactable content left is an un-splittable open tail step, it declines (returns `null`) and retries once an older step closes. **Single-unit overflow is out of scope, by design**: if one retained unit (a single closed step, or a large pasted `user/message`) ALONE exceeds the budget, compaction cannot help and the call may go out over-budget — bounding an individual unit's size is a separate concern. `compactRegion()` enforces tool-pairing balance strictly, throwing on a boundary that would split a step. `dsh-session` exports `isToolPairingBalanced` for the check.
-- **Dynamic convergence** — no static summary-length config pretends to bound what the model will write. If framing/estimator/system overhead leaves the compacted surface above threshold, `compactIfNeeded()` re-compacts the head checkpoint up to `compactionRetries` extra times; if it still cannot get below threshold, it throws. A summary whose estimated stored size is not smaller than the shadowed content fails closed before it mutates the surface.
-- **Summarization** — `summarize()`: a `GenerateOptions` request assembled via `BlockAssembler` with a fixed system prompt that asks for a structured checkpoint (Primary Request and Intent · Key Technical Concepts · Files and Code · Errors and Fixes · Pending Tasks · Current Work · Next Step · Critical Context), every section mandatory, exact paths/commands/identifiers preserved. The request is a direct one-shot `ctx.llm.stream()` call — NOT a loop step, so it does not run `agent/request` (that seam shapes the loop's conversation requests); the model comes from `summarizationModel` falling back to the agent's own, and per-call routing happens at `llm/stream` like any other direct call. `maxTokens` is the provider-side generation cap; only text blocks from the model's reply are kept before the checkpoint is stored (reasoning is dropped so private chain-of-thought never leaks into the durable summary, and a stray `tool-call` is dropped so the synthesized `user/message` summary cannot land an orphaned call with no matching `tool-result`). The compacted region is flattened to a plain-text transcript first: text and reasoning contribute their text, and every non-text block (tool-call, tool-result, plugin-added types) contributes a type-tagged placeholder (`[tool-call: name(args)]`, `[tool-result: …]`, …) so the summarizer is told what existed rather than silently dropping it.
-- **Checkpoint framing** — the raw summary is not landed directly. `compactRegion()` wraps it in a checkpoint preamble (so a resuming model reads it as a checkpoint, not a fresh user request, and builds on the captured context rather than restating it) plus `<compacted-summary>…</compacted-summary>` tags. Because region compaction can be invoked manually, a surface may hold several checkpoints, so the framing does not claim everything after it is recent or verbatim. The tags make a prior checkpoint detectable in the transcript on the next compaction cycle: the summarization prompt then instructs the model to merge it in place (preserve still-true facts, drop stale ones) rather than re-summarize it verbatim — a cheap incremental merge that needs no extra log/event machinery. The unframed summary stays on the `compact/summary` provenance event.
-- **Surface mutation** — `compactRegion()` appends the `compact/start` → `compact/summary` → `compact/end` log records and the single `user/message` replace node carrying the framed summary (see the interface README).
-- **Auto-compaction** — an `agent/pre-step` listener delegates to `compactIfNeeded()` before every step (not just a turn's first — a tool-heavy turn grows the surface mid-turn, so a runaway turn still compacts, and per-step firing is the only moment to rescue it before overflow). `agent/pre-step` is a serial (awaited, in-order) surface-mutation checkpoint that fires after `turn/start` and BEFORE the step opens (`step/start`) and its request history is derived, so compaction mutates the surface — with its log-only `compact/*` records landing cleanly outside any step — and the loop derives once from the result: no double-derive, and the listener cannot see (or need to rewrite) an already-assembled `messages` array. The listener owns no threshold logic of its own (the single token-pressure check lives in `compactIfNeeded()`); because Cordis `serial` bails early on non-void return values, the listener returns `void` and does not use the dispatcher's bail channel as a veto surface.
-- **Failure handling** — the `compact/start … compact/end` bracket is a log-recorded lock: it makes a crash mid-summarization a detectable orphan (a `compact/start` with no `compact/end`), records provenance, and prevents a concurrent compaction. Two failure paths: a **crash** (the loop dies mid-summarization) leaves a dangling `compact/start` that is inert — `compact/*` events are log-only, the surface replacement never landed, so the full history derives fine and generic turn-repair closes the turn; a **recoverable** failure (summarization throws but the loop survives) appends `compact/end` with its `error` field set, leaving the surface untouched so the call proceeds with full history. Core session repair stays compaction-agnostic by design — it never learns about `compact/*`.
+- **Estimation** — a configurable characters-per-token heuristic counts the current session prefix supplied to pre-step, derived history, and system prompt, matching the next request rather than stale logged prefix state.
+- **Retention** — compact the oldest whole surface units while preserving a recent tail and balanced tool-call/result cuts. Turn boundaries do not protect old steps inside a runaway turn. An open indivisible tail declines until it closes; a single unit larger than the budget remains out of scope.
+- **Convergence** — retry head-checkpoint compaction up to `compactionRetries`; reject a summary that does not shrink its source, and throw if retries cannot return below threshold.
+- **Summarization** — a direct `llm/stream` call uses the configured model and cap without running the loop-only `agent/request` seam. The input transcript preserves non-text blocks as tagged placeholders; only returned text enters the checkpoint, excluding reasoning and tool calls that would leak private reasoning or create an orphaned call.
+- **Framing** — the replacement user message marks established checkpoint context with `<compacted-summary>` tags. The raw summary remains on the provenance event, and later automatic cycles merge the prior checkpoint.
+- **Lifecycle** — `compactRegion()` records its start, summary, replacement, and end. The serial `agent/pre-step` listener checks pressure before every step, outside an open step, so a tool-heavy turn remains compactable and the loop derives history once after mutation.
+- **Failure handling** — an unmatched `compact/start` is an inert crash marker because no replacement landed. Recoverable failure records an error end and leaves the surface unchanged.
 
 `estimateContentTokens()` and `summarize()` are overridable hooks: a tokenizer-based or template-based backend can subclass `BasicCompactService` and override just those, reusing the retention walk and surface plumbing. `summarize()` returns the summary blocks together with the call envelope it actually used (`{ summary, model, maxTokens? }`) — the caller logs that envelope on the `compact/summary` provenance event, so an overriding backend reports its own envelope honestly.
 

packages/compact/compact-basic/src/index.ts

@@ -1,31 +1,8 @@
 /**
- * `BasicCompactService`: the first implementation of the
- * `@deepseek-ai/dsh-compact` seam. It owns the entire compaction strategy:
- *
- * - **Token estimation** — chars/`charsPerToken` heuristic (config, default 4)
- *   with per-block structural overhead.
- * - **Retention policy** — walk surface nodes tail→head, keep recent nodes up
- *   to a token budget, compact everything older. The cutoff is snapped forward
- *   to the next balanced tool-pairing boundary so a compacted region never
- *   splits a step's tool-call/result pair (an open tail step is never crossed —
- *   compaction declines and retries once it closes).
- * - **Summarization** — a direct one-shot `ctx.llm.stream()` call assembled
- *   via `BlockAssembler` with a fixed condense-the-history system prompt;
- *   NOT a loop step, so `agent/request` never fires — interception happens
- *   at `llm/stream` like any other direct call.
- * - **Surface mutation** — a single `user/message` replace node carries the
- *   summary; `compact/*` events are log-only lock + provenance records.
- * - **Auto-compaction** — an `agent/pre-step` listener delegates to
- *   {@link BasicCompactService.compactIfNeeded} before EVERY step (so a
- *   tool-heavy turn that grows the surface mid-turn still compacts); it owns the
- *   sole token-pressure check.
- *
- * A different backend (real tokenizer, template summarizer, turn-count
- * retention) either subclasses this and overrides the {@link
- * BasicCompactService.estimateContentTokens} / {@link
- * BasicCompactService.summarize} hooks, or implements the abstract
- * {@link CompactService} from scratch.
- *
+ * Basic compaction backend. It estimates request pressure, retains a recent
+ * tool-balanced surface tail, summarizes the older head through a one-shot model
+ * call, and replaces that head with one checkpoint. Auto-compaction runs before
+ * every step so a growing turn can compact its earlier closed steps.
  * @module @deepseek-ai/dsh-compact-basic
  */
 
@@ -54,15 +31,8 @@ const SUMMARY_OPEN_TAG = '<compacted-summary>'
 const SUMMARY_CLOSE_TAG = '</compacted-summary>'
 
 /**
- * The summarization system prompt: instructs the model to condense the
- * conversation into a fixed, fully-populated structure rather than freeform
- * bullets. The fixed structure guarantees coverage of the things a resuming
- * model needs (original intent, pending work, the next step, critical context)
- * and is stable across compaction cycles, so a prior checkpoint can be merged
- * in place. The final rule keys off {@link SUMMARY_OPEN_TAG}: when the
- * transcript already contains a prior checkpoint, the model consolidates rather
- * than re-summarizing it verbatim (a cheap incremental-merge that needs no
- * extra log/event machinery — the tag travels on the summary surface node).
+ * Fixed summary structure for resumable checkpoints. A tagged prior checkpoint
+ * is merged with newer history instead of copied forward verbatim.
  */
 const SUMMARIZE_SYSTEM_PROMPT = [
   'You are a compaction engine for an AI coding assistant. Condense the conversation transcript into a structured checkpoint that lets another model resume the work with no loss of essential context.',
@@ -100,29 +70,13 @@ const SUMMARIZE_SYSTEM_PROMPT = [
   `- If the transcript already contains a ${SUMMARY_OPEN_TAG} block, it is a PRIOR checkpoint. Do not copy it forward verbatim: preserve still-true facts, drop stale ones, and merge newer information into a single consolidated summary under the same structure.`,
 ].join('\n')
 
-/**
- * Framing prepended to the landed summary so a resuming model reads it as a
- * checkpoint rather than a fresh user request, and continues the task from it.
- * It summarizes an earlier span of the conversation; the messages that follow
- * are the continuation. Because region compaction can be invoked manually, a
- * surface may hold several checkpoints, so the framing does NOT claim that
- * everything after it is recent or verbatim — only that the captured context
- * should be built on, not restated.
- */
+/** Framing that makes a landed summary established context rather than a new request. */
 const CHECKPOINT_PREAMBLE =
   'This is an automatically generated checkpoint condensing an earlier span of the conversation to free up context. Treat the captured context as established background and build on it without restating it. Continue the task directly from the messages that follow, without acknowledging this checkpoint.'
 
 /**
- * Map a terminal `FinishReason` to the error a SUMMARIZATION must throw, or
- * `undefined` for an acceptable finish. `FinishReason` is merge-extensible.
- *
- * Compaction fails CLOSED on a truncated summary: `error`, `aborted`, AND
- * `max-tokens` all raise. Unlike an ordinary agent turn — where `max-tokens` is
- * a normal "the model hit its budget" outcome the loop keeps — a summary cut off
- * at the token cap is an INCOMPLETE checkpoint, and committing it would shadow
- * (discard) the real history it summarizes. Raising here keeps the original
- * surface intact (the caller appends `compact/end` with the error and the auto
- * path proceeds with full history). `stop`/future kinds are accepted.
+ * Map a terminal summary failure to an error. A max-token finish is rejected
+ * because committing an incomplete checkpoint would shadow the full history.
  */
 function finishError(finish: FinishReason): Error | undefined {
   switch (finish.kind) {
@@ -164,25 +118,8 @@ export class BasicCompactService extends CompactService {
     this.config = resolveConfig(config)
 
     if (this.config.auto) {
-      // Auto-compaction: delegate to compactIfNeeded before EVERY step. This is
-      // LOAD-BEARING for runaway-turn survival: a tool-heavy ReAct turn appends
-      // an assistant/message and a tool/result per step, so the surface (and the
-      // derived token count) grows WITHIN a turn. The only moment to rescue a
-      // turn that alone approaches the window is the next step's pre-step
-      // checkpoint; gating to a turn's first step would let a runaway turn
-      // overflow before the next turn's check. The listener owns NO threshold
-      // logic — compactIfNeeded is the single place that decides whether to
-      // compact, and its in-progress lock serializes concurrent attempts.
-      //
-      // It runs on `agent/pre-step` (a serial surface-mutation checkpoint fired
-      // AFTER turn/start but BEFORE step/start), NOT `agent/request`: compaction
-      // mutates the session surface, and the loop derives the request `messages`
-      // AFTER this fires — so a single derive already reflects the compaction,
-      // with no double-derive and no need to rewrite an already-assembled
-      // `messages` array. Firing pre-step (outside any open step) keeps the
-      // log-only `compact/*` records and the replacement node cleanly outside a
-      // step, so a crash mid-compaction leaves an inert orphan the turn-repair
-      // closes — never a half-open step.
+      // Check before every step so a single growing turn can compact earlier closed steps.
+      // This serial pre-step seam mutates the surface outside the pending step.
       ctx.on('agent/pre-step', async (agent: Agent, _turn: number, _step: number, fullSystemPrompt: string, sessionPrefix: readonly Message[], signal: AbortSignal) => {
         try {
           const result = await this.compactIfNeeded(agent, fullSystemPrompt, sessionPrefix, signal)
@@ -289,27 +226,9 @@ export class BasicCompactService extends CompactService {
   }
 
   /**
-   * Summarize conversation text into content blocks via `ctx.llm.stream()`
-   * assembled through a `BlockAssembler`. A direct one-shot model call, NOT a
-   * loop step: it does not run the `agent/request` waterfall (that seam shapes
-   * the loop's conversation requests); per-call
-   * interception happens at `llm/stream` like any other direct call. The model
-   * comes from `BasicCompactConfig.summarizationModel`, falling back to the
-   * agent's own model.
-   * Override in a subclass for a template or remote summarizer.
-   *
-   * Honors the adapter failure contract: an adapter may report a model failure
-   * by throwing from `stream()` (propagated here) OR by ending the stream with
-   * a `finish {kind:'error'|'aborted'}` chunk — the latter is re-thrown so a
-   * provider error never yields an empty summary.
-   *
-   * Forwards `signal` into `GenerateOptions.signal` so an abort/dispose tears
-   * down the in-flight summarization rather than orphaning the model call.
-   *
-   * Returns the summary blocks TOGETHER with the call envelope it actually
-   * used (`model`, `maxTokens`) — the caller logs the envelope on the
-   * `compact/summary` provenance event, so an overriding subclass (template
-   * or remote summarizer) reports its own envelope honestly.
+   * Summarize through a direct one-shot `ctx.llm.stream()` call, not an agent
+   * step or `agent/request` dispatch. Failure finishes and truncated summaries
+   * reject; the signal is forwarded and only text reaches the checkpoint.
    *
    * @param text - plain-text rendering of the conversation region to condense.
    * @param agent - supplies the fallback model and the session id stamped on
@@ -359,42 +278,10 @@ export class BasicCompactService extends CompactService {
   // ---- Core API (implements the abstract contract) ----
 
   /**
-   * The sole token-pressure gate: estimate the NEXT request's pressure — the
-   * session prefix + the surface-derived history + the system prompt
-   * ({@link estimatePressure}) — and if it exceeds the threshold
-   * (`contextWindow * thresholdRatio`), compact
-   * the oldest surface nodes outside the `retainTokens` budget. The auto-
-   * compaction listener delegates here rather than pre-checking, so this is the
-   * only place the decision lives. The prefix counts because every request
-   * carries it in front of the history (`EpochHeader.messagePrefix`) even
-   * though it is not derived history — omitting it would under-estimate by
-   * exactly the prefix and let a deployment at the window edge skip
-   * compaction, then ship an over-window request. The loop composes the
-   * prefix BEFORE the pre-step seam and hands it through, so the gate sees
-   * this instance's actual prefix (never a previous instance's logged one —
-   * a resumed/forked instance whose contributor grew is gated on the grown
-   * value from its very first step). Compaction itself can only
-   * shrink HISTORY: a prefix that alone approaches the window is a
-   * configuration error no compactor fixes.
-   *
-   * Retention is a UNIFORM tail→head walk over the whole surface — turn
-   * boundaries play NO role. Walking node-by-node from the tail and summing
-   * token estimates, once the retained total reaches `retainTokens` the cutoff
-   * is rounded to a balanced tool-pairing boundary: if the cut before the
-   * retained node is unbalanced (an unanswered tool-call sits before it — i.e.
-   * it is mid-step), the walk continues head-ward until the cut is balanced so
-   * the whole step is retained (never splitting a step's tool-calls from their
-   * results); if it stopped on a free node (a node belonging to no step), that
-   * cut is already balanced. This always rounds toward retaining MORE (retained
-   * ≥ `retainTokens`) and is boundary-safe by construction — no separate snap
-   * pass.
-   *
-   * The compacted range is always anchored at the surface HEAD (`nodes[0]`):
-   * auto-compaction re-consolidates any prior head checkpoint into one fresh
-   * checkpoint. Declines (`null`) when nothing is over threshold, when the whole
-   * surface fits the retain budget, or when no balanced cutoff exists in the
-   * compactable range (its only content is an open tail step — retry once it
-   * closes).
+   * The sole pressure gate: count the next request's prefix, derived history,
+   * and system prompt. Above threshold, retain a recent tool-balanced tail and
+   * compact the head, reconsolidating any prior automatic checkpoint. Returns
+   * `null` when no safe or necessary range exists.
    */
   override async compactIfNeeded(
     agent: Agent,
@@ -450,13 +337,7 @@ export class BasicCompactService extends CompactService {
     agent: Agent,
     signal?: AbortSignal,
   ): Promise<CompactionResult> {
-    // Resolve the range by surface POSITION, not numeric seq interval. A prior
-    // replace lands a fresh high-seq summary node AT the shadowed range's
-    // position, so the surface order (head→tail) no longer tracks seq order —
-    // `[newSummarySeq, olderRetainedSeq, …]` is normal. Indexing into the
-    // ordered node list and slicing it is the only correct way to read a range;
-    // a `node.seq >= start && node.seq <= end` interval test would mis-collect
-    // nodes (and `start > end` would falsely reject) once that happens.
+    // Resolve by surface position: a newer replacement seq may occupy an older slot.
     const nodes = session.surface.nodes
     const startIdx = nodes.findIndex(n => n.seq === start)
     const endIdx = nodes.findIndex(n => n.seq === end)
@@ -466,14 +347,7 @@ export class BasicCompactService extends CompactService {
       throw new Error(`compactRegion: start seq ${start} (position ${startIdx}) is after end seq ${end} (position ${endIdx}) on the surface`)
     }
 
-    // The region must never split a step's assistant-message tool-calls from
-    // their tool/results (which would orphan one side and produce a transcript
-    // every provider rejects). A region is safe iff BOTH its edges are balanced
-    // cuts: the cut before `start`, and the cut after `end`. A node that belongs
-    // to no step (pre-step user message, inter-step steering, injection context)
-    // is a balanced (free) boundary; an `end` inside an open (unclosed) tail step
-    // leaves the cut after it unbalanced (the open tool-call has no result yet),
-    // so it is rejected. See dsh-session's tool-pairing balance check.
+    // Both range edges must preserve assistant tool-call/result pairing.
     const events = session.events
     if (!isToolPairingBalanced(nodes, events, start)) {
       throw new Error(`compactRegion: start seq ${start} is not a balanced boundary (would split a step's tool-call/result pair)`)
@@ -490,13 +364,8 @@ export class BasicCompactService extends CompactService {
       throw new Error('compaction already in progress')
     }
 
-    // Compaction's events (compact/* and the replacement user/message) must be
-    // turn-enclosed: the session-log contract rejects any plugin event appended
-    // outside an open turn. Auto-compaction satisfies this — it runs on the
-    // `agent/pre-step` seam, after `turn/start` and before `step/start`, so
-    // strictly inside the open turn (but outside any step). A manual call on a
-    // fully-closed session has no turn to enclose the events, so reject rather
-    // than emit an un-enclosed run.
+    // Compaction's events (compact/* and the replacement user/message) must be turn-enclosed:
+    // the session-log contract rejects any plugin event appended outside an open turn.
     const openTurn = this._openTurn(session)
     if (openTurn === null) {
       throw new Error('compactRegion: no open turn — compaction events must be enclosed in a turn')
@@ -537,13 +406,8 @@ export class BasicCompactService extends CompactService {
         ...maxTokens !== undefined ? { maxTokens } : {},
       })
 
-      // --- Surface replacement ---
-      // The user/message directly shadows all compacted surface nodes with a
-      // single replace op. It is the ONLY surface event in the compaction
-      // sequence — compact/start, compact/summary, and compact/end are log-only
-      // (surfaceOp is rejected by the compiler for non-SurfaceEventType).
-      // The landed content is FRAMED (checkpoint preamble + tag-wrapped summary);
-      // the compact/summary provenance event above holds the raw model output.
+      // --- Surface replacement --- The user/message directly shadows all compacted surface
+      // nodes with a single replace op.
       session.append('user/message', {
         content: framedSummary,
         source: { kind: 'plugin', plugin: 'compact' },
@@ -597,17 +461,8 @@ export class BasicCompactService extends CompactService {
   }
 
   /**
-   * Whether a compaction is currently in progress for `session` — an unmatched
-   * `compact/start` (no later `compact/end`) WITHIN the current turn.
-   *
-   * The scan is scoped to the current turn: walking back from the tail it stops
-   * at the first `turn/end` (the boundary closing the prior turn). A
-   * `compact/start` left orphaned by a crash mid-compaction lives in a turn that
-   * persistence repair then closes with a synthetic `turn/end`; scoping here so
-   * that a stale orphan from a PAST turn cannot wedge compaction forever (it sits
-   * before the nearest `turn/end`, so the scan never reaches it). An in-progress
-   * compaction's `compact/start` is always in the still-open current turn,
-   * before any `turn/end`, so it is still detected.
+   * Whether a compaction is currently in progress for `session` — an unmatched `compact/start`
+   * (no later `compact/end`) WITHIN the current turn.
    */
   private _isCompactionInProgress(session: Session): boolean {
     const events = session.events
@@ -650,14 +505,10 @@ export class BasicCompactService extends CompactService {
     // The whole surface fits the retain budget — nothing to compact.
     if (keepFromIdx === 0) return null
 
-    // Round the cutoff to a tool-pairing boundary: if the cut before
-    // `nodes[keepFromIdx]` is unbalanced (an unanswered tool-call sits before
-    // it — i.e. it is mid-step), extend the retained side head-ward until the
-    // cut is balanced, so the compacted range ends without splitting an
-    // assistant↔result pair. A node that belongs to no step is already a
-    // balanced (free) boundary. Decline if no balanced cut exists at or below
-    // `keepFromIdx` (the compactable range is only an un-splittable open tail
-    // step — retry once it closes).
+    // Round the cutoff to a tool-pairing boundary: if the cut before `nodes[keepFromIdx]` is
+    // unbalanced (an unanswered tool-call sits before it — i.e. it is mid-step), extend the
+    // retained side head-ward until the cut is balanced, so the compacted range ends without
+    // splitting an assistant↔result pair.
     while (keepFromIdx > 0) {
       // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
       if (isToolPairingBalanced(nodes, events, nodes[keepFromIdx]!.seq)) break
@@ -673,17 +524,7 @@ export class BasicCompactService extends CompactService {
     return { start: firstSeq, end: cutoffSeq }
   }
 
-  /**
-   * Keep ONLY text blocks from the model-produced summary before storing it.
-   *
-   * The summary lands on the surface as a synthesized `user/message` (see
-   * {@link _frameSummary}), so the only block type that is both useful and safe
-   * there is `text`. A model assistant message can otherwise carry `reasoning`
-   * (private chain-of-thought, must not leak into the durable checkpoint) and
-   * `tool-call` blocks — and a surviving `tool-call` in a user message would be
-   * an orphaned call with no matching `tool-result`, exactly the tool-pairing
-   * breakage compaction works to avoid. Filtering to text drops both.
-   */
+  /** Keep only text; checkpoints cannot contain reasoning or orphan tool calls. */
   private _textOnly(blocks: readonly ContentBlock[]): ContentBlock[] {
     return blocks.filter((block): block is Extract<ContentBlock, { type: 'text' }> => block.type === 'text')
   }

packages/compact/compact-basic/src/types.ts

@@ -48,13 +48,6 @@ export type ResolvedConfig = Required<BasicCompactConfig>
 /**
  * Default `auto`/`charsPerToken` when unset and reject nonsensical numeric knobs.
  *
- * Convergence is not a static config invariant: provider generation caps can be
- * spent on hidden or surfaced reasoning tokens, and the model may emit a summary
- * of unpredictable size. The backend instead enforces convergence dynamically:
- * each committed summary must be smaller than the content it shadows, and
- * `compactIfNeeded` may re-compact up to `compactionRetries` extra times before
- * throwing if the surface still exceeds the threshold.
- *
  * @param config - the raw, unresolved backend config.
  * @returns the validated config with `auto` and `charsPerToken` defaulted.
  */

packages/compact/compact-basic/tests/compact-basic.spec.ts

@@ -82,15 +82,7 @@ function createTestService(overrides: Partial<BasicCompactConfig> = {}): TestCom
   return new TestCompactService(new Context(), cfg({ auto: false, ...overrides }))
 }
 
-/**
- * Build a multi-turn session with surface markers (simulating real agent-loop
- * output). Compaction always runs inside an OPEN turn (the loop fires the
- * `agent/pre-step` seam after a turn's start and before a step's start), so by
- * default the session is left with a trailing open turn: turns `1..turns`
- * close, then one more `turn/start` opens with no matching `turn/end`. Pass
- * `{ leaveOpen: false }` for a fully-closed session (e.g. to assert that manual
- * compaction is rejected when no turn is open).
- */
+/** Build closed turns plus an open compaction turn unless `leaveOpen` is false. */
 function multiTurnSession(turns: number, messagesPerTurn: number = 2, opts: { leaveOpen?: boolean } = {}): Session {
   const leaveOpen = opts.leaveOpen ?? true
   const s = new Session(SessionId('test'))
@@ -211,12 +203,8 @@ function expectNoOrphanToolResults(messages: Message[]): void {
 
 describe('BasicCompactService step-alignment (never split a tool-call/result pair)', () => {
   it('compactIfNeeded rounds the retained boundary head-ward to keep a whole step (no orphaned tool-result)', async () => {
-    // 3 turns, each one step = { assistant(tool-call), tool/result }. Surface
-    // (9 nodes): user1, asst1, res1, user2, asst2, res2, user3, asst3, res3 —
-    // 10/20/10 tokens. The tail→head walk retains by whole units; the compacted
-    // region always ends on a step boundary, so no step's tool-call is split
-    // from its result. retainTokens=55 keeps the recent tail; the older steps
-    // compact intact.
+    // Retain the recent tail while the older assistant/result pairs compact as
+    // whole units; no boundary may orphan a result.
     const svc = createTestService({ contextWindow: 280, thresholdRatio: 0.5, retainTokens: 55 })
     const session = toolTurnSession(3)
 
@@ -231,12 +219,8 @@ describe('BasicCompactService step-alignment (never split a tool-call/result pai
   })
 
   it('compactIfNeeded returns null when the only compactable region is an un-splittable single step', async () => {
-    // The surface is exactly ONE step: [assistant(tool-call), tool/result]. Over
-    // threshold (by the derived role overhead), the tail→head walk stops with the
-    // retained boundary at the tool/result — which is NOT a step-aligned start (its
-    // issuing assistant precedes it in the same step). Rounding head-ward to find a
-    // clean boundary reaches index 0, so there is no step-aligned cutoff in the
-    // compactable range: compactIfNeeded declines rather than splitting the step.
+    // The only candidate cut is inside one assistant/result pair; with no safe
+    // compactable prefix, decline rather than split it.
     const s = new Session(SessionId('one-step'))
     s.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
     s.append('step/start', { turn: 1, step: 1 })
@@ -605,27 +589,16 @@ describe('BasicCompactService.compactIfNeeded', () => {
   })
 
   it('returns null when the whole surface fits the retain budget (over threshold by role/system overhead)', async () => {
-    // threshold = floor(480*0.1) = 48. The 4 surface nodes weigh 10 each (raw 40
-    // for the retention walk), but the derived estimate adds 4 role tokens per
-    // message → 56 ≥ 48, so the threshold check passes and the walk runs. The
-    // walk accumulates all 40 < retainTokens (45) without crossing the budget,
-    // so keepFromIdx reaches 0 and compaction declines.
+    // Role overhead pushes the request above its 48-token threshold, but the
+    // raw four-node retention walk remains below retainTokens=45, so all fit.
     const svc = createTestService({ contextWindow: 480, thresholdRatio: 0.1, retainTokens: 45 })
     const session = multiTurnSession(2, 1)
     expect(await compactIfNeeded(svc, session, '', 'm', SIGNAL)).toBeNull()
   })
 
   it('compacts a runaway turn: its early CLOSED steps summarize while recent steps stay verbatim', async () => {
-    // The REGRESSION that motivated dropping turn-protection. A single in-flight
-    // (open) turn has grown past the threshold on its own: several CLOSED steps,
-    // each [assistant(tool-call), tool/result]. Retention is turn-agnostic, so
-    // the turn's OWN early closed steps are eligible — they compact while the
-    // recent tail stays verbatim, and the harness survives.
-    //
-    // On the OLD layer-2 code this test FAILS: the entire open turn was retained
-    // verbatim (protectedIdx = first open-turn node = 0), so compactIfNeeded
-    // returned null and shadowedSeqs would be empty — the runaway turn could
-    // never compact and the next model call would overflow the window.
+    // Completed early steps of the open turn remain eligible; protecting the
+    // whole turn would make a runaway turn impossible to compact.
     const svc = createTestService({ contextWindow: 800, thresholdRatio: 0.1, retainTokens: 25 })
     const s = new Session(SessionId('runaway'))
     // ONE open turn with 5 closed steps; each step is [asst(tool-call), result].
@@ -665,12 +638,7 @@ describe('BasicCompactService.compactIfNeeded', () => {
   })
 
   it('compacts again after a prior summary node heads the surface (the summary stays eligible)', async () => {
-    // After the first compaction lands a replacement summary node at the head,
-    // a second compaction (still over threshold) re-consolidates it with newer
-    // context — head-anchoring means the prior checkpoint is always re-included,
-    // never stranded. retainTokens=25 leaves a couple of retained nodes after
-    // the first compaction (so the surface is [summary, …retained], not just
-    // [summary]).
+    // Head-anchored recompaction must include the previous summary and retained context.
     const svc = createTestService({ contextWindow: 800, thresholdRatio: 0.1, retainTokens: 25 })
     const s = multiTurnSession(4, 1) // turns 1-4 closed, turn 5 open (no surface yet)
 
@@ -776,10 +744,8 @@ describe('BasicCompactService blocking (compaction in progress)', () => {
   })
 
   it('is not wedged by an orphaned compact/start from a prior (now-closed) turn', async () => {
-    // A crash mid-compaction left a compact/start with no compact/end; the turn
-    // it lived in was later closed (persistence repair appends turn/end). A
-    // whole-log scan would treat that stale start as an active lock forever. The
-    // scan is scoped to the current turn, so a NEW turn compacts normally.
+    // An orphaned start in a closed repaired turn is stale; only the current
+    // turn participates in the in-progress lock.
     const svc = createTestService()
     const s = new Session(SessionId('stale-lock'))
     s.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
@@ -860,11 +826,8 @@ describe('BasicCompactService HMR safety', () => {
   })
 
   it('disposing the plugin fiber unregisters ctx.compact', async () => {
-    // Mount through the real plugin fiber (the Loader path), then dispose it and
-    // confirm the service registration is torn down. LlmService is mounted first
-    // so the service's `inject: ['llm']` resolves and the fiber activates. (The
-    // sibling-fiber ctx.llm resolution this same setup also exercises is covered
-    // under the "llm inject (real plugin-load path)" suite.)
+    // Mount through the real plugin fiber (the Loader path), then dispose it and confirm the
+    // service registration is torn down.
     const ctx = new Context()
     await ctx.plugin(LlmService)
     const fiber = await ctx.plugin(BasicCompactService, cfg({ auto: false }))
@@ -1259,11 +1222,8 @@ describe('BasicCompactService auto-compaction (agent/pre-step listener)', () =>
 
   it('summarization is interceptable at llm/stream (model routing for direct calls)', async () => {
     const { ctx, adapter } = await ctxWithModel('ROUTED SUMMARY', 'routed-model')
-    // The summarize call is a direct one-shot model call, not a loop step: it
-    // does not run agent/request (that seam shapes the loop's conversation
-    // requests). llm/stream is its interception surface, and a hand-built
-    // request is not frozen, so mutate-then-next model routing works — the
-    // adapter resolves AFTER the waterfall, so the rewrite picks the adapter.
+    // One-shot summaries bypass agent/request but remain mutable at llm/stream;
+    // adapter selection happens after the waterfall rewrite.
     ctx.on('llm/stream', (options, next) => {
       options.model = 'routed-model'
       return next()
@@ -1517,19 +1477,13 @@ describe('BasicCompactService edge cases', () => {
     const svc = createTestService()
     const s = new Session(SessionId('empties'))
     s.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
-    // Step 1: an empty-text user, an empty-reasoning assistant with NO tool-call
-    // (balanced: nothing to answer), and empty context/steering — all extract to
-    // nothing and are skipped.
     s.append('step/start', { turn: 1, step: 1 })
     s.append('user/message', { content: [{ type: 'text', text: '' }], source: { kind: 'user' } }, { surfaceOp: 'append' })
     s.append('assistant/message', { turn: 1, step: 1, content: [{ type: 'reasoning', text: '' }] }, { surfaceOp: 'append' })
     s.append('context/message', { content: [], source: { kind: 'user' } }, { surfaceOp: 'append' })
     s.append('steering/message', { turn: 1, content: [{ type: 'text', text: '' }], source: { kind: 'user' } }, { surfaceOp: 'append' })
     s.append('step/end', { turn: 1, step: 1 })
-    // Step 2: a tool exchange whose tool/result has empty content → empty
-    // extraction → skipped. The assistant carries the matching tool-call so the
-    // surface stays tool-pairing balanced; its text extracts to the tool-call
-    // placeholder (the one surviving line).
+    // Keep the log pairing-valid while the empty result covers the final message kind.
     s.append('step/start', { turn: 1, step: 2 })
     s.append('assistant/message', {
       turn: 1, step: 2,
@@ -1543,10 +1497,6 @@ describe('BasicCompactService edge cases', () => {
 
     const nodes = s.surface.nodes
     await compactRegion(svc, s, nodes[0]!.seq, nodes[nodes.length - 1]!.seq, 'm')
-    // Every empty-content message (user text, empty reasoning, empty-content
-    // tool/result, empty context, empty steering) extracted to nothing and was
-    // skipped — the only surviving line is the assistant's tool-call (which a
-    // balanced surface requires to answer the tool/result).
     expect(svc.summarizeCalls[0]!.text).toBe('Assistant: [tool-call: bash({})]')
   })
 
@@ -1594,40 +1544,26 @@ describe('BasicCompactService edge cases', () => {
 
 describe('BasicCompactService positional range (surface seqs are not monotonic after a replace)', () => {
   it('compacts a second region after the first replace lands a high-seq summary at the head position', async () => {
-    // A replace inserts the new summary node (a high seq) AT the shadowed
-    // range's surface position, so the surface becomes
-    // [highSeqSummary, …olderRetainedLowerSeqs]. A second compaction over a
-    // range whose start node has a HIGHER seq than its end node must still
-    // succeed — the range is positional, not a numeric seq interval.
+    // Replacement makes surface seqs non-monotonic. The next region is a
+    // positional span even when startSeq > endSeq.
     const svc = createTestService({ auto: false })
     const session = multiTurnSession(4, 1)
 
-    // First compaction: shadow the two oldest surface nodes.
+    // A replacement puts its high-seq summary at the surface head.
     const nodes0 = session.surface.nodes
     const first = await compactRegion(svc, session, nodes0[0]!.seq, nodes0[1]!.seq, 'm')
 
-    // The summary node now sits at the head with a seq HIGHER than the
-    // retained older nodes that follow it — the non-monotonic surface. (The
-    // head is the user/message replace node, appended after the compact/summary
-    // provenance event, so its seq is at least first.summarySeq.)
     const nodes1 = session.surface.nodes
     expect(nodes1[0]!.seq).toBeGreaterThanOrEqual(first.summarySeq)
     expect(nodes1[0]!.seq).toBeGreaterThan(nodes1[1]!.seq)
 
-    // Second compaction: shadow [summary(head) … turn-2's step end]. The start
-    // seq (the head summary node) is GREATER than the end seq (an older retained
-    // node), so the range is a SURFACE-POSITION span, not a numeric seq interval.
-    // The end must land on a step boundary (turn-2's assistant message closes
-    // its step).
     const startSeq = nodes1[0]!.seq
     const endSeq = nodes1[2]!.seq
     expect(startSeq).toBeGreaterThan(endSeq)
     const second = await compactRegion(svc, session, startSeq, endSeq, 'm')
 
-    // Exactly the three nodes at surface positions [0..2] are shadowed, in
-    // surface order — the positional slice, regardless of their seq values.
+    // Selection follows surface positions, not sequence-number order.
     expect(second.shadowedSeqs).toEqual([nodes1[0]!.seq, nodes1[1]!.seq, nodes1[2]!.seq])
-    // The surface still derives cleanly: a new head replace node + the rest.
     const finalNodes = session.surface.nodes
     expect(finalNodes[0]!.seq).toBeGreaterThanOrEqual(second.summarySeq)
     expect(session.deriveMessages().length).toBe(finalNodes.length)
@@ -1637,20 +1573,15 @@ describe('BasicCompactService positional range (surface seqs are not monotonic a
     const svc = createTestService({ auto: false })
     const session = multiTurnSession(3, 1)
 
-    // First compaction shadows the oldest two surface nodes, landing a high-seq
-    // summary node at the head.
+    // Put a high-seq summary at the head; log order would place retained older nodes first.
     const n0 = session.surface.nodes
     await compactRegion(svc, session, n0[0]!.seq, n0[1]!.seq, 'm')
 
-    // Second compaction spans [head summary … turn-2's step end]. The head's seq
-    // is higher than the older retained nodes' seqs, so a log-seq-order walk
-    // would emit the older messages BEFORE the checkpoint.
     const n1 = session.surface.nodes
     svc.summarizeCalls = []
     await compactRegion(svc, session, n1[0]!.seq, n1[2]!.seq, 'm')
 
-    // The extracted transcript follows surface order: the checkpoint (head)
-    // first, then the older retained messages — matching deriveMessages().
+    // Extraction must match surface and `deriveMessages()` order.
     const { text } = svc.summarizeCalls[0]!
     const checkpointIdx = text.indexOf('compacted-summary')
     const olderIdx = text.indexOf('turn 2 user')
@@ -1661,10 +1592,8 @@ describe('BasicCompactService positional range (surface seqs are not monotonic a
 
 describe('BasicCompactService llm inject (real plugin-load path)', () => {
   it('declares llm in static inject so a sibling fiber can resolve ctx.llm', () => {
-    // summarize() reads ctx.llm; the inject lets the cordis ctx proxy resolve a
-    // sibling LlmService when this service is mounted as its own plugin fiber.
-    // Asserting the declaration (and exercising the real mount below) guards the
-    // resolution that root-ctx unit tests cannot, since they share one fiber.
+    // summarize() reads ctx.llm; the inject lets the cordis ctx proxy resolve a sibling
+    // LlmService when this service is mounted as its own plugin fiber.
     expect(BasicCompactService.inject).toContain('llm')
   })
 

packages/compact/compact-basic/tests/compact-loop-repro.spec.ts

@@ -14,24 +14,10 @@ import { BasicCompactService } from '@deepseek-ai/dsh-compact-basic'
 import type { SurfaceEvent } from '@deepseek-ai/dsh-session'
 
 /**
- * CBR-001 regression: a compaction checkpoint that the REAL loop lands is a
- * free surface boundary (it carries no tool-call/result pair), so it must be a
- * valid region edge on BOTH sides. A surface-anchored balance check sees that;
- * the abandoned log-position scan did not.
- *
- * The loop fires the compaction seam mid-flight, so the landed checkpoint
- * `user/message{replace}` sits at a HIGH log seq positioned beside the current
- * step even though its SURFACE position is the head. A log-position forward scan
- * from the checkpoint reaches the step's own later `assistant/message` and
- * wrongly reports the checkpoint as mid-step — refusing it as a region end. A
- * SECOND compaction that re-summarizes just that head checkpoint (region end ==
- * checkpoint) therefore throws and is swallowed, so the surface never
- * re-consolidates.
- *
- * This drives a real auto-compaction through the agent-loop and asserts the
- * landed checkpoint balances on both sides AND that re-compacting it (end ==
- * checkpoint) succeeds. RED on the log-position predicates; GREEN once alignment
- * is decided from surface tool-pairing balance.
+ * CBR-001 regression through the real loop. A replacement checkpoint has a high
+ * log seq at the surface head and carries no tool pair, so both adjacent cuts
+ * must be safe and re-compacting that checkpoint alone must succeed. This pins
+ * surface-position semantics rather than raw-log scanning.
  */
 
 const TOKENS_PER_BLOCK = 10
@@ -132,14 +118,8 @@ describe('CBR-001: a real-loop checkpoint is a valid boundary on both sides', ()
       )
       expect(checkpoints.length).toBeGreaterThan(0)
 
-      // The loop fired compaction mid-flight, so each landed checkpoint sits at a
-      // high log seq beside the step it landed in, even though its SURFACE
-      // position is the head of the range it shadowed. A checkpoint carries no
-      // tool-call/result pair (only summarized prose), so every checkpoint still
-      // on the surface must be a balanced cut on BOTH sides — the cut before it
-      // (region START) and the cut after it (region END). The abandoned
-      // log-position scan reported the END as mis-aligned because the forward log
-      // scan reached the neighbouring step's assistant/message.
+      // High log position does not make a text-only checkpoint mid-step; both
+      // its start and end cuts are balanced in surface order.
       const nodes = agent.session.surface.nodes
       for (const cp of checkpoints) {
         const node = nodes.find(n => n.seq === cp.seq)

packages/compact/compact/src/index.ts

@@ -1,23 +1,9 @@
 /**
- * The compaction service seam (`ctx.compact`): an abstract service defining
- * WHAT compaction does — decide when to compact, summarize a range of
- * conversation history into a single surface node — without saying HOW.
- *
- * Implementations subclass {@link CompactService}, implement
- * {@link CompactService.compactIfNeeded} and {@link CompactService.compactRegion},
- * and load as a plugin — registering as `ctx.compact` (one implementation per
- * context). A tokenizer-, template-, or model-backed implementation can live
- * as a sibling package; callers stay on the same `ctx.compact` seam without
- * touching consumers.
- *
- * The split follows the capability-seams RFC — interface (this) /
- * implementation (`dsh-compact-basic`) / consumer (a `/compact` tool, deferred) — modeled
- * on the bash trio. Unlike `dsh-bash`, this interface necessarily
- * depends on `dsh-session` and `dsh-llm`: the contract's verbs are defined over
- * a `Session` and its output is the `ContentBlock` vocabulary. That deviation
- * from the "interface depends only on cordis" guidance is intentional and
- * recorded in the [compaction capability-seam RFC](../../../../docs/rfc/implemented/feature/2026-06-18-compaction-capability-seam.md).
- *
+ * Compaction service seam (`ctx.compact`): implementations decide when to
+ * compact and replace a history range with one summary node by subclassing
+ * {@link CompactService}. This interface necessarily depends on session and LLM
+ * vocabulary; the rationale is in the
+ * [compaction RFC](../../../../docs/rfc/implemented/feature/2026-06-18-compaction-capability-seam.md).
  * @module @deepseek-ai/dsh-compact
  */
 
@@ -42,25 +28,10 @@ declare module 'cordis' {
 }
 
 /**
- * Abstract compaction service. Subclass implement the two abstract methods,
- * and load the subclass as a plugin — it registers as `ctx.compact` (one
- * implementation per context; loading a second throws, which is cordis'
- * standard duplicate-service behavior).
- *
- * Both core methods are abstract: the contract states WHAT compaction does,
- * while the entire strategy — token estimation, retention policy, event
- * sequencing, summarization — is a HOW decision owned by the implementation.
- *
- * Implementations MUST honor:
- * - **Surface contract**: a successful compaction shadows the compacted surface
- *   nodes with a SINGLE replacement node carrying the summary. Because
- *   `SurfaceEventType` is a closed union, that node is a `user/message` with
- *   `surfaceOp: { op:'replace', start, end }`; the `compact/*` events are
- *   log-only (lock + provenance).
- * - **Blocking**: no compaction begins while another is in progress for the
- *   same session. The recommended mechanism is the log-recorded lock — append
- *   `compact/start` before the slow work and `compact/end` after (even on
- *   failure) — so the lock is visible to replay and crash recovery.
+ * Abstract compaction service. Implementations own token estimation, retention,
+ * and summarization, but a successful run must replace the selected surface span
+ * with one summary node and prevent concurrent compaction of the same session.
+ * Load one implementation per context as `ctx.compact`.
  */
 export abstract class CompactService extends Service {
   constructor(ctx: Context) {
@@ -69,43 +40,17 @@ export abstract class CompactService extends Service {
 
   /**
    * Check token pressure and compact if the conversation is too large.
-   *
-   * Estimates the NEXT request's size — the session prefix, the
-   * surface-derived history, and the system prompt — and if it exceeds the
-   * backend's threshold, compacts an older range
-   * via {@link compactRegion}, keeping recent context intact. Returns `null`
-   * when no compaction is needed.
-   *
-   * Scope and guarantees a backend MUST honor:
-   * - **Compaction acts on surface-derived history only**, but the ESTIMATE
-   *   counts everything the request carries: the loop composes the session
-   *   prefix before the pre-step seam fires and hands it here, so the gate
-   *   sees the prefix this instance will actually send (`EpochHeader.messagePrefix`
-   *   — request-only, never derived history). Non-surface context injected
-   *   downstream (into the request `messages` by a later listener) is out of
-   *   this accounting by construction.
-   * - **Head-anchored, best-effort.** Auto-compaction consolidates from the
-   *   surface HEAD up to a balanced tool-pairing cutoff, so a prior head
-   *   checkpoint is
-   *   re-summarized into one fresh checkpoint (the surface holds at most one
-   *   auto-generated checkpoint, always at the head). It is best-effort over
-   *   CLOSED steps: when the only compactable content left is an un-splittable
-   *   open tail step, it declines (`null`) and retries once that step closes.
-   * - **Single-unit overflow is out of scope.** If a single retained unit (one
-   *   closed step, or a large free node such as a pasted `user/message`) ALONE
-   *   exceeds the budget, compaction cannot help and the call may go out
-   *   over-budget. Bounding an individual unit's size is a separate concern —
-   *   as is a session prefix that alone approaches the window (a
-   *   configuration error no compactor fixes: compaction cannot shrink the
-   *   prefix).
+   * Estimate the next request, including its session prefix, derived history,
+   * and system prompt. Above threshold, compact a head-anchored range ending at
+   * a balanced tool boundary and reconsolidate any prior automatic checkpoint.
+   * Return `null` when no compaction is needed or an open tail leaves no safe
+   * cutoff. A single oversized retained unit or prefix cannot be repaired here.
    *
    * @param agent - agent context owning the session surface and model options.
    * @param fullSystemPrompt - assembled system prompt, counted toward the estimate.
-   * @param sessionPrefix - the instance's composed session prefix, counted toward the estimate.
-   * @param signal - cancellation signal. A backend summarizing via
-   *   `ctx.llm.stream()` MUST forward this into the call's `GenerateOptions.signal`
-   *   so an abort/dispose tears down the in-flight summarization rather than
-   *   leaving an orphaned model call running past the cancellation.
+   * @param sessionPrefix - the instance's composed session prefix, counted toward the
+   *   estimate.
+   * @param signal - cancellation signal; model-backed implementations must forward it.
    * @returns the compaction result, or `null` if no compaction was needed.
    */
   abstract compactIfNeeded(
@@ -117,36 +62,19 @@ export abstract class CompactService extends Service {
 
   /**
    * Forcibly compact a range of surface nodes into a single summary node.
+   * `start` and `end` name an inclusive span by surface position, not numeric seq
+   * order; replacements can make visible seqs non-monotonic. Both edges must be
+   * balanced so assistant tool calls remain paired with their results. A model-
+   * backed implementation forwards cancellation and rejects active, missing,
+   * reversed, or unbalanced ranges.
    *
-   * `start` and `end` are inclusive seqs of surface nodes to shadow; the backend
-   * summarizes their content and appends a replacement surface node. Used by the
-   * (future) `/compact` tool and internally by {@link compactIfNeeded}.
-   *
-   * The region MUST NOT split a step's `assistant/message` tool-calls from their
-   * `tool/result`s, leaving the rehydrated transcript with a dangling tool-call
-   * or an orphaned tool-result that every provider rejects. A region is safe iff
-   * both its edges are balanced cuts on the surface: the cut before `start` and
-   * the cut after `end` each have no unanswered tool-call before them. A node
-   * that belongs to no step (a pre-step user message, inter-step steering, or an
-   * injection context message) is a balanced (free) boundary; an `end` inside an
-   * open (unclosed) tail step is invalid — its tool-calls have no results yet.
-   * `dsh-session` exports `isToolPairingBalanced` for this check.
-   *
-   * @param session - the session whose surface is mutated.
-   * @param start - inclusive seq of the first surface node to compact.
-   * @param end - inclusive seq of the last surface node to compact.
-   * @param agent - agent context used by router-aware summarizers.
-   * @param signal - optional cancellation signal. A backend that summarizes via
-   *   `ctx.llm.stream()` MUST forward this into the call's `GenerateOptions.signal`
-   *   so an abort/dispose tears down the in-flight summarization rather than
-   *   leaving an orphaned model call running past the cancellation.
-   * @throws if compaction is already in progress, if `start`/`end` are not
-   *   valid surface nodes, if `start` is positioned after `end` on the surface
-   *   (the range is a surface-POSITION span, not a numeric seq interval — a
-   *   prior replace can leave the surface non-monotonic in seq order), or if
-   *   either boundary is not a balanced tool-pairing cut (would split a step's
-   *   tool-call/result pair).
-   * @returns what the compaction did (the replaced range and its summary node).
+   * @param session - session to mutate.
+   * @param start - first surface seq, inclusive.
+   * @param end - last surface seq, inclusive.
+   * @param agent - summarizer context.
+   * @param signal - optional cancellation; model-backed implementations must forward it.
+   * @throws when compaction is active or the range is missing, reversed, or unbalanced.
+   * @returns the replaced range and summary.
    */
   abstract compactRegion(
     session: Session,

packages/compact/compact/src/render.ts

@@ -1,16 +1,6 @@
 /**
- * Plain-text transcript rendering over session events: the shared projection
- * used wherever a compaction-class consumer needs "what a model once saw" as
- * readable text — a summarizer's input, or a recall tool's output.
- *
- * Extracted from the basic backend's private helpers so the summarize path and
- * the recall read path render one span identically (two renderers would drift,
- * and a recall reader would then see a different transcript than the one the
- * summary was written from). Both functions are pure over their arguments: no
- * session access beyond the provided events, no clock, no randomness — a
- * rendered span is a pure function of the log, so replay reproduces it
- * byte-identically.
- *
+ * Pure shared transcript projection for summarization and recall, so both
+ * render the same log span byte-for-byte under replay.
  * @module @deepseek-ai/dsh-compact/render
  */
 
@@ -18,14 +8,9 @@ import type { ContentBlock } from '@deepseek-ai/dsh-llm'
 import type { SessionEvent } from '@deepseek-ai/dsh-session'
 
 /**
- * Render content blocks to a single plain-text string. Text and reasoning
- * contribute their text (reasoning wrapped as `[reasoning: …]`); every other
- * block type contributes a type-tagged placeholder (`[tool-call: name(args)]`,
- * `[tool-result: …]`, …) so the reader is told what non-text content existed
- * rather than silently losing it. A `tool-result` block recurses into its
- * nested content (`[tool-result: <inner rendering>]`), falling back to a bare
- * `[tool-result]` when the nested content renders to nothing. Blocks join
- * with newlines; empty-text blocks contribute nothing.
+ * Render text directly, reasoning as a tagged span, and every other block as a
+ * type-tagged placeholder. Tool results recurse into nested content; empty
+ * blocks contribute nothing and rendered blocks join with newlines.
  *
  * @param blocks - the content blocks to render.
  * @returns the newline-joined plain-text rendering; empty string when nothing renders.
@@ -59,17 +44,9 @@ export function renderContentBlocks(blocks: readonly ContentBlock[]): string {
 }
 
 /**
- * Render a set of surface-node seqs as a `User:`/`Assistant:`/`Tool result:`
- * transcript. Walks `seqs` in the order given — callers pass surface order
- * (e.g. a `compactRegion` slice of the surface-node list), which after a
- * `replace` is NOT ascending log-seq order (a high-seq summary node can sit at
- * the head of the surface before older retained lower-seq nodes); a log-order
- * scan would render the transcript out of order.
- *
- * Only the five surface (message-producing) event types render; a seq naming
- * any other event type contributes nothing. `SessionEventMap` is
- * merge-extensible, so unknown types are simply non-message events with no
- * renderable text.
+ * Render message-producing events as a role-labeled transcript. `seqs` are
+ * walked in caller-supplied surface order, which may differ from numeric log
+ * order after replacement; non-surface and unknown merged events are skipped.
  *
  * @param events - the session log the seqs index into (`session.events`).
  * @param seqs - the surface-node seqs to render, in surface order.

packages/compact/compact/src/types.ts

@@ -1,17 +1,9 @@
 /**
  * Compaction vocabulary: the result type and the `compact/*` session events.
- *
- * Extends {@link SessionEventMap} with `compact/*` event types via declaration
- * merging. {@link SurfaceEventType} is deliberately NOT extended — `compact/*`
- * events are log-only markers (lock + provenance); only the five
- * surface-eligible types can carry `surfaceOp`. The actual surface mutation is
- * performed by a separate `user/message` event carrying the summary (see the
- * [compaction capability-seam RFC](../../../../docs/rfc/implemented/feature/2026-06-18-compaction-capability-seam.md)).
- *
- * Configuration lives in the backend, not here: the contract states WHAT
- * compaction produces, while every tunable (context window, thresholds,
- * retention budget) is a HOW decision owned by the implementation.
- *
+ * Those declaration-merged events are log-only lock/provenance markers, not
+ * surface events; a separate replacement `user/message` carries the summary.
+ * Backend packages own configuration and retention policy; see
+ * `docs/rfc/implemented/feature/2026-06-18-compaction-capability-seam.md`.
  * @module @deepseek-ai/dsh-compact/types
  */
 

packages/cordis/tool-cordis/README.md

@@ -12,7 +12,7 @@ Exact model-facing schemas: [the generated tool catalog](../../../docs/tool-cata
 
 ## Trust stance
 
-The sandbox isolates the global context only — it is not a security boundary. No Node API is provided: `require`, the timers, and `fetch` are callable traps that throw a redirect to the cordis alternative (`ctx.fs` / `ctx.web` / `ctx.bash` / `inject: ['timer']` + `ctx.setTimeout`); `process` and `Buffer` are `undefined`; `globalThis` writes stay inside. These traps steer honest code onto the cordis services; they do not contain a mount that goes looking — the host-realm helpers on the sandbox global (`harness`, `console`, `btoa`) are reachable functions, so mount code can reach the host realm and Node through one of them, which is fine because `ctx` is fully privileged anyway. The `ctx` a mounted plugin's `apply` receives is a whitelist façade — register tools, observe events, provide/consume services, use timers; framework internals (`ctx.root`, `ctx.fiber`, `ctx.extend`, `ctx.plugin`, …) are withheld — but the capabilities it does expose reach the real runtime, so load this plugin as deliberately as you would grant a bash tool.
+The sandbox isolates globals but is not a security boundary. Node globals are absent or redirect to Cordis services such as `ctx.fs`, `ctx.web`, and `ctx.bash`, and writes to `globalThis` stay local, but host-realm helpers make escape possible. Mounted plugins receive a façade without framework internals, yet its allowed services affect the live runtime. Treat this toolset like bash access; see the [design and trust stance](../../../docs/rfc/implemented/feature/2026-07-08-self-referential-cordis-toolset.md).
 
 ## Config
 

packages/cordis/tool-cordis/src/api-catalog.ts

@@ -77,14 +77,14 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
   },
   {
     key: 'approval',
-    summary: 'The `ctx.approval` service: dispatches ApprovalRequests to the `approval/request` waterfall and audits every ask/outcome pair to the requesting agent\'s session log.',
+    summary: 'Approval service that applies session policy before answerers and logs every ask/outcome pair to the requesting session.',
     methods: [
       'async request(req: ApprovalRequest): Promise<ApprovalOutcome>',
     ],
   },
   {
     key: 'bash',
-    summary: 'Abstract bash execution service.',
+    summary: 'Registers one `ctx.bash` implementation.',
     methods: [
       'abstract resolve(request: BashExecRequest): BashExecSpec',
       'abstract run(spec: BashExecSpec): Promise<BashRunResult>',
@@ -99,7 +99,7 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
   },
   {
     key: 'codeRuntime',
-    summary: 'Abstract code-execution service.',
+    summary: 'Registers one `ctx.codeRuntime` implementation.',
     methods: [
       'abstract run(request: CodeRunRequest): Promise<CodeRunResult>',
     ],
@@ -114,7 +114,7 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
   },
   {
     key: 'fs',
-    summary: 'Abstract filesystem provider service.',
+    summary: 'Abstract filesystem provider.',
     methods: [
       'abstract resolve(path: string, opts?: { cwd?: string }): Promise<FsTarget>',
       'abstract stat(target: FsTarget, signal?: AbortSignal): Promise<FsInfo | undefined>',
@@ -136,7 +136,7 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
   },
   {
     key: 'permission',
-    summary: 'The permission service (`ctx.permission`).',
+    summary: 'Owns the deployment\'s permission presets and their write path.',
     methods: [
       'current(events: readonly SessionEvent[]): string',
       'resolve(name: string): PresetSpec',
@@ -153,7 +153,7 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
   },
   {
     key: 'sessionPersistence',
-    summary: 'Abstract durable session-persistence service.',
+    summary: 'Durable append-only session storage.',
     methods: [
       'abstract create(meta: SessionHeader): Promise<void>',
       'abstract append(id: SessionId, events: readonly SessionEvent[]): Promise<void>',
@@ -206,7 +206,7 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
   },
   {
     key: 'systemPrompt',
-    summary: 'Registry service (`ctx.systemPrompt`): plugins contribute ordered text sections, tool-schema providers, and named prompt variables; the agent loop calls `assemble(context)` once per step.',
+    summary: 'Registry service for the prompt inputs assembled before each model step.',
     methods: [
       'section(section: PromptSection): () => void',
       'tools(provider: (context: AssembleContext) => ToolProviderResult): () => void',
@@ -216,7 +216,7 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
   },
   {
     key: 'tools',
-    summary: 'Tool registry (`ctx.tools`): tool plugins register definitions; the agent loop executes calls through the `tools/pre-execute` → guards → `tools/execute` → `tools/post-execute` → `tools/result` pipeline.',
+    summary: 'Tool registry and execution pipeline.',
     methods: [
       'register(definition: ToolDefinition): () => void',
       'restrict(filter: ToolRestriction): () => void',
@@ -246,7 +246,7 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
   },
   {
     key: 'workflows',
-    summary: 'Abstract workflow execution service.',
+    summary: 'Workflow execution seam.',
     methods: [
       'abstract start(request: WorkflowStartRequest): WorkflowRun',
     ],
@@ -259,13 +259,13 @@ export const EVENT_API: readonly EventApiEntry[] = [
     name: 'agent/created',
     mode: 'emit',
     signature: '\'agent/created\'(this: Scoped<Agent>, agent: Agent): void',
-    summary: 'An agent\'s fully composed scoped world was published in the AgentRegistry.',
+    summary: 'A fully configured agent and live session were published.',
   },
   {
     name: 'agent/disposed',
     mode: 'emit',
     signature: '\'agent/disposed\'(this: Scoped<Agent>, agent: Agent): void',
-    summary: 'An agent was removed from the registry.',
+    summary: 'An agent left the registry; AgentLoop emits this after driver quiescence but before session detachment and scoped-registration unwind.',
   },
   {
     name: 'agent/error',
@@ -277,37 +277,37 @@ export const EVENT_API: readonly EventApiEntry[] = [
     name: 'agent/pre-step',
     mode: 'serial',
     signature: '\'agent/pre-step\'(this: Scoped<Agent>, agent: Agent, turn: number, step: number, fullSystemPrompt: string, sessionPrefix: readonly Message[], signal: AbortSignal): Promise<void> | void',
-    summary: 'Awaited pre-step surface-mutation checkpoint, fired once per step AFTER `turn/start` (and after the prior step closed) but BEFORE this step\'s `step/start` — so anything a listener appends lands OUTSIDE the step, between `turn/start`/`step/end` and the upcoming `step/start`.',
+    summary: 'Awaited serial checkpoint for session-surface mutation after prompt assembly and before `step/start`; appends land outside the pending step.',
   },
   {
     name: 'agent/prompt-submit',
     mode: 'waterfall',
     signature: '\'agent/prompt-submit\'(this: Scoped<Agent>, agent: Agent, content: ContentBlock[], source: MessageSource, next: () => Promise<PromptDecision>): Promise<PromptDecision>',
-    summary: 'Waterfall: decide what happens to ONE drained queued message before it becomes a `user/message` — allow (optionally rewriting the prompt bytes or attaching `additionalContext`) or block it.',
+    summary: 'Allow, rewrite, or block one drained prompt before it becomes a user message.',
   },
   {
     name: 'agent/queued',
     mode: 'emit',
     signature: '\'agent/queued\'(this: Scoped<Agent>, agent: Agent, content: ContentBlock[], info: { source: MessageSource; steering: boolean }): void',
-    summary: 'A message entered the agent\'s inbox (queued or steering).',
+    summary: 'Detached, frozen content entered the agent\'s inbox.',
   },
   {
     name: 'agent/request',
     mode: 'waterfall',
     signature: '\'agent/request\'(this: Scoped<Agent>, agent: Agent, turn: number, step: number, config: LlmCallConfig, next: () => Promise<LlmCallConfig>): Promise<LlmCallConfig>',
-    summary: 'Waterfall: shape the step\'s call configuration — model switching, sampling overrides — by returning a replacement LlmCallConfig (the frozen seed is the config the loop would otherwise use).',
+    summary: 'Replace the frozen call configuration.',
   },
   {
     name: 'agent/session-prefix',
     mode: 'waterfall',
     signature: '\'agent/session-prefix\'(this: Scoped<Agent>, agent: Agent, prefix: Message[], signal: AbortSignal, next: () => Promise<Message[]>): Promise<Message[]>',
-    summary: 'Waterfall: compose the SESSION PREFIX — request-only messages placed in front of the ENTIRE derived history (directly after the provider\'s system slot) on every request this loop instance sends.',
+    summary: 'Compose request-only messages placed before derived history.',
   },
   {
     name: 'agent/session-start',
     mode: 'emit',
     signature: '\'agent/session-start\'(this: Scoped<Agent>, agent: Agent, source: SessionStartSource): void',
-    summary: 'The agent\'s session lifecycle began, fired once before its first turn.',
+    summary: 'The session lifecycle began, once before the first turn.',
   },
   {
     name: 'agent/status',
@@ -325,37 +325,37 @@ export const EVENT_API: readonly EventApiEntry[] = [
     name: 'agent/turn-continuation',
     mode: 'waterfall',
     signature: '\'agent/turn-continuation\'(this: Scoped<Agent>, agent: Agent, turn: number, defaultDecision: ContinuationDecision, next: () => Promise<ContinuationDecision>): Promise<ContinuationDecision>',
-    summary: 'Waterfall: override the turn-continuation decision via a typed ContinuationDecision.',
+    summary: 'Override whether the turn continues.',
   },
   {
     name: 'agent/turn-stop',
     mode: 'serial',
     signature: '\'agent/turn-stop\'(this: Scoped<Agent>, agent: Agent, turn: number): ContinuationStop | undefined',
-    summary: 'Serial terminal-stop checkpoint after the ordinary `agent/turn-continuation` waterfall, any `continue.reason`, and the pending-steering continuation override have been folded.',
+    summary: 'Monotonic terminal-stop checkpoint after continuation and steering are folded; a stop remains authoritative through turn close and flush: steering queued in that window is discarded, while ordinary sends survive.',
   },
   {
     name: 'approval/request',
     mode: 'waterfall',
     signature: '\'approval/request\'(this: Scoped<ApprovalService>, req: ApprovalRequest, next: () => Promise<ApprovalOutcome>): Promise<ApprovalOutcome>',
-    summary: 'Waterfall asking the composed answerers to decide one approval request.',
+    summary: 'Ask composed answerers for one decision.',
   },
   {
     name: 'fs/edit-intent',
     mode: 'waterfall',
     signature: '\'fs/edit-intent\'(target: FsTarget, actor: object | undefined, next: () => { version: FsVersion } | undefined | Promise<{ version: FsVersion } | undefined>): Promise<{ version: FsVersion } | undefined>',
-    summary: 'Single-slot decision: produce the optional version guard for the next FileSystem.editText.',
+    summary: 'Single-slot decision for the next FileSystem.editText.',
   },
   {
     name: 'fs/observed',
     mode: 'emit',
     signature: '\'fs/observed\'(target: FsTarget, version: FsVersion, actor: object | undefined): void',
-    summary: 'Record that an actor observed a target at a version, after a successful read/write/edit.',
+    summary: 'Record a successful observation.',
   },
   {
     name: 'fs/write-intent',
     mode: 'waterfall',
     signature: '\'fs/write-intent\'(target: FsTarget, actor: object | undefined, next: () => FsWriteIntent | undefined | Promise<FsWriteIntent | undefined>): Promise<FsWriteIntent | undefined>',
-    summary: 'Single-slot decision: produce the write intent for the next FileSystem.writeText.',
+    summary: 'Single-slot decision for the next FileSystem.writeText.',
   },
   {
     name: 'llm/stream',
@@ -367,25 +367,25 @@ export const EVENT_API: readonly EventApiEntry[] = [
     name: 'session/created',
     mode: 'emit',
     signature: '\'session/created\'(this: Scoped<Session>, session: Session): void',
-    summary: 'A session was created in the store.',
+    summary: 'Creation announcement during session publication.',
   },
   {
     name: 'session/disposed',
     mode: 'emit',
     signature: '\'session/disposed\'(this: Scoped<Session>, session: Session): void',
-    summary: 'A previously announced session left the store.',
+    summary: 'Emitted once when an announced session leaves the store, including publication rollback, but never for an entry whose creation announcement did not begin.',
   },
   {
     name: 'session/event',
     mode: 'emit',
     signature: '\'session/event\'(this: Scoped<Session>, session: Session, event: SessionEvent): void',
-    summary: 'An event was appended to a session log (sync, fire-and-forget).',
+    summary: 'Post-commit, fire-and-forget append feed.',
   },
   {
     name: 'session/flush',
     mode: 'parallel',
     signature: '\'session/flush\'(this: Scoped<Session>, session: Session): Promise<void> | void',
-    summary: 'Awaited durability checkpoint.',
+    summary: 'Awaited parallel durability checkpoint: every listener runs and the caller awaits all of them, with no waterfall veto.',
   },
   {
     name: 'skill/provider-added',
@@ -427,13 +427,13 @@ export const EVENT_API: readonly EventApiEntry[] = [
     name: 'system-prompt/assemble',
     mode: 'waterfall',
     signature: '\'system-prompt/assemble\'(this: Scoped<SystemPrompt>, assembly: PromptAssembly, context: AssembleContext, next: () => Promise<PromptAssembly>): Promise<PromptAssembly>',
-    summary: 'Waterfall around prompt assembly — mutate or extend the PromptAssembly (sections + tools + variables) before it is rendered.',
+    summary: 'Expert waterfall over the assembled sections, tools, and variables.',
   },
   {
     name: 'system-prompt/change',
     mode: 'emit',
     signature: '\'system-prompt/change\'(): void',
-    summary: 'A section, tool provider, or variable provider was registered or unregistered (the assembly inputs changed — possibly for one scope only).',
+    summary: 'Emitted when any prompt provider changes.',
   },
   {
     name: 'tools/change',
@@ -445,25 +445,25 @@ export const EVENT_API: readonly EventApiEntry[] = [
     name: 'tools/execute',
     mode: 'waterfall',
     signature: '\'tools/execute\'(this: Scoped<ToolRegistry>, exec: ToolExecution, next: () => Promise<ToolExecutionResult>): Promise<ToolExecutionResult>',
-    summary: 'Around-dispatch waterfall wrapping the registry\'s core tool dispatch, between the `tools/pre-execute` gate and the `tools/post-execute` seam.',
+    summary: 'Around-dispatch waterfall for timeout, retry, or metrics.',
   },
   {
     name: 'tools/post-execute',
     mode: 'waterfall',
     signature: '\'tools/post-execute\'(this: Scoped<ToolRegistry>, exec: ToolExecution, result: Readonly<ToolExecutionResult>, next: () => Promise<PostToolDecision>): Promise<PostToolDecision>',
-    summary: 'Waterfall AFTER a tool runs — where hook plugins inspect the result and accept it (optionally REPLACING the model-facing content, and/or attaching `additionalContext` for the next request) or block it with corrective `feedback` (Claude Code\'s `PostToolUse`).',
+    summary: 'Accept, replace, enrich, or block a normalized dispatch result.',
   },
   {
     name: 'tools/pre-execute',
     mode: 'waterfall',
     signature: '\'tools/pre-execute\'(this: Scoped<ToolRegistry>, exec: ToolExecution, next: () => Promise<PreToolDecision>): Promise<PreToolDecision>',
-    summary: 'Waterfall BEFORE a tool runs — the gate where sandbox, permission, and hook plugins allow or deny a call (Claude Code\'s `PreToolUse`).',
+    summary: 'Allow, deny, or ask before dispatch.',
   },
   {
     name: 'tools/result',
     mode: 'emit',
     signature: '\'tools/result\'(this: Scoped<ToolRegistry>, exec: Readonly<ToolExecution>, result: Readonly<ToolExecutionResult>): undefined',
-    summary: 'Synchronous notification of the authoritative FINAL tool outcome, after the complete pre/execute/post pipeline, final lossless-JSON validation, and outer error normalization.',
+    summary: 'Observe the frozen, lossless-JSON final outcome.',
   },
   {
     name: 'workflow/agent-end',

packages/cordis/tool-cordis/src/fiber-state.ts

@@ -1,15 +1,7 @@
 /**
- * Runtime mirror of the cordis `FiberState` const enum plus human-readable
- * labels, shared by the mount lifecycle (state reporting) and the inspect
- * renderers (plugin-list and mount-table labels).
- *
- * Cordis exposes `FiberState` as a `const enum`: there is no runtime object for
- * Node's type-stripping runner to import, so the members are mirrored here as
- * values — each typed (via the type-only import) as the cordis enum member it
- * mirrors, so enum-typed reads like `fiber.state` compare against them under a
- * shared enum type. Source of truth: vendor/cordis/src/fiber.ts (pinned; drift
- * only happens through a deliberate vendor sync).
- *
+ * Runtime mirror and labels for Cordis's `FiberState` const enum. A const enum has no runtime
+ * object to import, so these values mirror the pinned vendored definition while retaining its
+ * type.
  * @module @deepseek-ai/dsh-tool-cordis/fiber-state
  */
 

packages/cordis/tool-cordis/src/guard.ts

@@ -1,50 +1,14 @@
 /**
- * The registration boundary between sandboxed mount code and the real runtime:
- * SchemaSpec normalization + validation with teaching errors, the
- * marker-guarded `harness.defineTool` / `harness.registerTool` pair, the
- * SANDBOX CONTEXT FAÇADE a mounted plugin's `apply` receives in place of the
- * real `ctx`, and the plugin-shape helpers the mount lifecycle narrows sandbox
- * return values with.
- *
- * The façade is a WHITELIST, not a pass-through proxy. Mount code needs to do
- * exactly four things — register a tool, listen to an event, provide a service,
- * call an injected service (timers included) — so the façade exposes only those
- * verbs and the injected services, each object-valued service individually
- * wrapped (a primitive provided value passes through as-is — see
- * {@link sandboxContext}). Every framework plumbing member (`root`, `parent`, `scope`, `fiber`, `reflect`, `registry`,
- * `events`, `extend`, `isolate`, `intercept`, `plugin`, `set`, `mixin`, …) is
- * DENIED with a teaching error rather than passed through. This closes an
- * entire escape class at once: a pass-through proxy that only special-cased
- * `ctx.tools` still handed back the raw context through `ctx.root`,
- * `ctx.extend()`, or a service instance's `.ctx`, and mount code could then
- * `ctx.root.tools.register({…})` to bypass the marker check and host-realm
- * normalization — a raw vm-realm result then errors a real agent turn at the
- * session-log plainness check. The whitelist has no such hole: there is no
- * context-valued member to reach, and any injected-service method that returns
- * a `Context` is rejected (harness services never do — see {@link denyContext}).
- *
- * Two realm facts drive the tool path. Objects built inside the vm carry the vm
- * realm's `Object.prototype`, and the session log's append-time plainness check
- * (`dsh-session`'s `isJsonValue`, a prototype-identity comparison) rejects
- * foreign-realm data — so every dynamic tool's `execute` return is JSON
- * round-tripped into the host realm and shape-checked against the two
- * `ToolExecuteReturn` forms before it reaches the registry (the registry
- * trusts the shape blindly — it spreads `result.content`, so an unvalidated
- * `{ content: 'ok' }` would enter the session log as `['o','k']` and silently
- * corrupt the next model request), and the schema itself is rebuilt as fresh
- * host-realm objects. And a malformed tool
- * schema must fail at REGISTRATION, not when a later request assembles it — so
- * dynamic tool registration accepts only definitions produced by the sandbox's
- * `harness.defineTool`, which normalizes `parameters` up front.
- *
- * Normalize, don't lecture, where the input has exactly one meaning: models
- * write the JSON-Schema dialect by strong prior (the `{ type: 'object',
- * properties, required: […] }` wrapper, `type: 'integer'`, `required: false`),
- * and each rejection costs a model turn — so those convert to the SchemaSpec
- * DSL silently, and only genuinely meaningless input (an unknown type, a
- * non-boolean `required`) is rejected, with the error enumerating the valid
- * vocabulary.
+ * The registration boundary between sandboxed mount code and the real runtime: SchemaSpec
+ * normalization + validation with teaching errors, the marker-guarded `harness.defineTool` /
+ * `harness.registerTool` pair, the SANDBOX CONTEXT FAÇADE a mounted plugin's `apply` receives
+ * in place of the real `ctx`, and the plugin-shape helpers the mount lifecycle narrows sandbox
+ * return values with. The façade is a whitelist of lifecycle-safe verbs and declared services;
+ * framework internals and context-valued service returns are denied.
  *
+ * VM-realm schemas are rebuilt as host objects, and tool results are JSON-round-tripped and
+ * shape-checked before session logging. Common JSON-Schema spellings are normalized when they
+ * have one meaning; invalid vocabulary fails during registration with a teaching error.
  * @module @deepseek-ai/dsh-tool-cordis/guard
  */
 
@@ -102,7 +66,7 @@ function normalizeSchemaProp(value: unknown, path: string, forceRequired = false
   }
   // On an object property a JSON-Schema-style `required` ARRAY names required
   // children (handled by the nested unwrap below); everywhere else `required`
-  // must be a boolean, and `false` simply reads as optional.
+  // must be a boolean, and `false` means optional.
   const nestedRequiredArray = type === 'object' && Array.isArray(value.required)
   if (value.required !== undefined && typeof value.required !== 'boolean' && !nestedRequiredArray) {
     throw new Error(`harness.defineTool ${path}.required must be a boolean when present`)
@@ -195,14 +159,11 @@ function assertExecuteReturn(value: unknown): ToolExecuteReturn {
 }
 
 /**
- * The `harness.defineTool` handed into the sandbox: the real DSL, with
- * `parameters` normalized into a fresh host-realm SchemaSpec (JSON-Schema
- * wrapper unwrapped, `integer` mapped, `required: false` dropped) and the
- * tool's `execute` return normalized into the host realm via a JSON round-trip
- * (see the module doc). The round-trip projects the return onto exactly what
- * the log would durably store, and {@link assertExecuteReturn} then vets that
- * projection — so a non-JSON-serializable OR wrong-shape return surfaces as
- * that one call's teaching error instead of poisoning the turn.
+ * The `harness.defineTool` handed into the sandbox: the real DSL, with `parameters` normalized
+ * into a fresh host-realm SchemaSpec (JSON-Schema wrapper unwrapped, `integer` mapped,
+ * `required: false` dropped) and the tool's `execute` return normalized into the host realm
+ * via a JSON round-trip. Non-JSON or wrong-shape output fails that call instead of poisoning
+ * the session log.
  * @param options - the standard `defineTool` options; `parameters` may be the SchemaSpec DSL or a JSON-Schema-style wrapper.
  * @returns the marker-tagged definition `harness.registerTool` (and the guarded `ctx.tools.register`) accepts.
  */
@@ -236,15 +197,9 @@ export function sandboxRegisterTool(ctx: Context, tool: unknown): () => void {
 }
 
 /**
- * The verbs a mounted plugin may reach through the sandbox `ctx` façade,
- * beyond its injected services. `on`/`once` observe events, `provide` exposes
- * a service to other mounts, and the timer helpers schedule work — each a
- * fiber effect that unwinds on unmount. Everything else on a real cordis `ctx`
- * is framework plumbing and is denied. Forwarded LAZILY: the timer helpers are
- * mixin accessors that throw `without inject` when read on a plugin that did
- * not inject `timer`, so the façade reads `ctx[verb]` only at call time — the
- * plugin that never touches a timer never trips that, and one that does gets
- * cordis's own inject error at the call site.
+ * The verbs a mounted plugin may reach through the sandbox `ctx` façade, beyond its injected
+ * services. `on`/`once` observe events, `provide` exposes a service to other mounts, and the
+ * timer helpers schedule work — each a fiber effect that unwinds on unmount.
  */
 const CTX_VERBS = new Set(['on', 'once', 'provide', 'timeout', 'interval', 'setTimeout', 'setInterval', 'throttle', 'debounce'])
 
@@ -258,11 +213,7 @@ const CTX_VERBS = new Set(['on', 'once', 'provide', 'timeout', 'interval', 'setT
  * name/description/parameters view as `schemas()`, and nothing invocable.
  */
 function sandboxTools(ctx: Context): Record<string, unknown> {
-  // Reads resolve through the MOUNT's own scope (`scopeOf(ctx)`), mirroring
-  // where the façade's `register` lands its writes (the calling context's
-  // layer): mount code always sees the tools its own world sees — the global
-  // view for today's global mounts, its agent's view if a mount ever runs
-  // under an agent scope.
+  // Resolve reads and writes through the mount's own scope.
   return {
     register: (tool: unknown): (() => void) => sandboxRegisterTool(ctx, tool),
     schemas: () => ctx.tools.schemas(scopeOf(ctx)),
@@ -320,15 +271,8 @@ function declaredInjects(ctx: Context): Set<string> {
 }
 
 /**
- * The sandbox context façade handed to a mounted plugin's `apply` in place of
- * the real `ctx`. A whitelist (see the module doc): the registration/eventing
- * verbs, the timer helpers, a guarded `tools`, and injected services resolved
- * through a guarded `get` / property access. A service is reachable only if the
- * plugin DECLARED it in `inject` — an undeclared service is denied even when a
- * global provider exists, so cordis's activation/unload semantics (park the
- * mount when a declared provider goes away) actually bind. Every
- * framework-plumbing member is denied with a teaching error; there is no
- * context-valued member to reach.
+ * Whitelist context for mounted plugins: lifecycle-safe verbs, guarded tools, and only declared
+ * injected services. Framework plumbing is denied, and service methods cannot return a Context.
  */
 function sandboxContext(ctx: Context): Context {
   const tools = sandboxTools(ctx)
@@ -348,16 +292,8 @@ function sandboxContext(ctx: Context): Context {
       + 'Framework internals (root, fiber, registry, extend, plugin, …) are withheld by design.',
     )
   }
-  // Read a service for either access path (property or `get`). `tools` is the
-  // façade's own surface. An UNDECLARED name is denied with the teaching
-  // error; a DECLARED one resolves to the guarded service. A declared inject
-  // is required in cordis (the fiber only activates once every declared
-  // service is live), so at `apply`/`execute` time `ctx.get(name)` is present
-  // for a declared name — no undefined case to handle here. `provide()`
-  // accepts ANY value though (cross-mount composition advertises
-  // `ctx.provide('name', value)`), so a primitive or null value passes
-  // through unwrapped: Proxy throws on a non-object target, and only an
-  // object can carry a method that hands back a Context.
+  // Read a service for either access path (property or `get`). `tools` is the façade's own
+  // surface.
   const readService = (name: string): unknown => {
     if (name === 'tools') return tools
     if (!declared.has(name)) return denyRead(name)
@@ -408,20 +344,11 @@ export function isPlugin(value: unknown): value is Plugin {
 }
 
 /**
- * Wrap a plugin so its `apply` receives the sandbox context façade instead of
- * the real `ctx` (see {@link sandboxContext} and the module doc). Both
- * function-form and object-form plugins go through the same wrap; the plugin's
- * own `inject` declaration is preserved (cordis reads it from the plugin
- * object, and pending/active gating happens on the real fiber before `apply`
- * runs), so cross-mount provide/inject works unmodified.
- *
- * `ctx.effect(customCleanup)` is deliberately absent from the façade for now —
- * `on` / `provide` / `tools.register` cover every mount seen so far, and each
- * is already a fiber effect. FIXME(sandbox-effect): expose a guarded `effect`
- * once a real mount needs a bespoke disposer.
+ * Wrap a plugin so `apply` receives the sandbox context while preserving injection metadata.
  * @param plugin - the plugin the mount code returned.
  * @returns an equivalent plugin whose `apply` sees the sandbox context façade.
  */
+// FIXME(sandbox-effect): expose guarded custom effects when a mount needs bespoke cleanup.
 export function guardedPlugin(plugin: Plugin): Plugin {
   if (typeof plugin === 'function') {
     const functionPlugin = plugin as (ctx: Context, config?: unknown) => unknown

packages/cordis/tool-cordis/src/index.ts

@@ -1,37 +1,9 @@
 /**
- * The self-referential cordis toolset: three model-facing tools that let the
- * agent inspect and MODIFY the live cordis runtime it is running inside.
- *
- * - `cordis_inspect` — read-only: provided services, the flat plugin list
- *   with lifecycle states, registered tools, the dynamic mounts, and the
- *   catalog-backed `api` / `events` references.
- * - `cordis_mount` — evaluate model-written code in a `node:vm` sandbox; the
- *   code returns a cordis plugin, which is mounted as a child of a dedicated
- *   `cordis-dynamic` group fiber and tracked under an id (`dyn-1`, `dyn-2`, …).
- * - `cordis_unmount` — dispose one dynamic mount by id, awaiting quiescence.
- *
- * Everything the model's plugin registers (listeners via `ctx.on`, tools via
- * `harness.registerTool`, services via `ctx.provide`) is an effect on the
- * dynamic fiber, so unmounting — or disposing this plugin itself (HMR) — cleans
- * it all up through the ordinary cordis lifecycle. The group fiber exists
- * exactly so the dynamic mounts form ONE subtree, disposed as a unit with
- * this plugin. Design home:
- * docs/rfc/implemented/feature/2026-07-08-self-referential-cordis-toolset.md.
- *
- * The vm sandbox guards against ACCIDENTAL global pollution only, and the `ctx`
- * a mounted plugin's `apply` receives is a WHITELIST façade (register a tool,
- * observe events, provide/consume services, use timers — framework internals
- * withheld; see the guard module). Neither is a security boundary: the verbs
- * the façade DOES expose reach the real runtime unsandboxed (a mounted tool can
- * shell out through `ctx.bash`), so a deployment loads this plugin as
- * deliberately as it grants a bash tool. Design home:
- * docs/rfc/implemented/feature/2026-07-08-self-referential-cordis-toolset.md.
- *
- * Plugin export shape: named exports, NO default. The cordis Loader's
- * `unwrapExports` does `exports.default ?? exports`, so a stray default would
- * collapse the module to the bare `apply` and drop `inject`, crashing at load
- * (see docs/postmortem/0001).
- *
+ * Self-referential runtime tools: inspect live services/plugins/tools, mount a returned plugin
+ * under an owned dynamic fiber, and unmount it to quiescence. Registrations are fiber effects,
+ * so plugin disposal removes the entire dynamic subtree. The VM and context façade prevent
+ * accidental misuse, not hostile code: an allowed service such as `ctx.bash` reaches the real
+ * runtime. Named exports preserve loader injection metadata.
  * @module @deepseek-ai/dsh-tool-cordis
  */
 
@@ -75,9 +47,7 @@ type ResolvedConfig = Required<Config>
  */
 export function apply(ctx: Context, config: Config): void {
   const { vmTimeoutMs } = config as ResolvedConfig
-  // The one group fiber every dynamic mount hangs under. Mounted here (a child
-  // of this plugin's fiber) so disposing tool-cordis cascades over the whole
-  // dynamic subtree — the ordinary parent→child fiber lifecycle, nothing extra.
+  // The one group fiber every dynamic mount hangs under.
   const group = ctx.plugin({ name: 'cordis-dynamic', apply: () => {} })
 
   const mounts = new Map<string, DynamicMount>()

packages/cordis/tool-cordis/src/inspect.ts

@@ -1,11 +1,7 @@
 /**
- * Read-only renderers over the live runtime for `cordis_inspect`: the service
- * list, the flat plugin list, the registered tools, the dynamic-mount
- * table (with per-mount provides/waits), and the catalog-backed `api` /
- * `events` sections. Every renderer is a pure function of the runtime handles
- * it receives — no session state, no clock — so inspect output is exactly the
- * runtime it describes.
- *
+ * Read-only renderers over the live runtime for `cordis_inspect`: the service list, the flat
+ * plugin list, the registered tools, the dynamic-mount table (with per-mount provides/waits),
+ * and the catalog-backed `api` / `events` sections.
  * @module @deepseek-ai/dsh-tool-cordis/inspect
  */
 
@@ -131,16 +127,13 @@ function typeClosure(seeds: string[], types: readonly TypeApiEntry[]): TypeApiEn
 }
 
 /**
- * The `api` section: the generated service catalog intersected with the LIVE
- * runtime — catalogued live services render summary + method signatures, live
- * services without a catalog entry (e.g. ones another mount provides) render
- * name + owning fiber, catalog services that are not running are listed
- * tersely, the type shapes the live signatures reference follow, and the
- * inherited `ctx` surface closes the section.
+ * Render the generated catalog against the live runtime: live catalogued services with methods,
+ * uncatalogued live services with owners, absent loadable services, referenced type shapes, and
+ * inherited Context APIs.
  * @param ctx - the runtime to intersect the catalog with.
- * @param api - the service catalog (the generated one by default; injectable for tests).
- * @param inherited - the inherited `ctx` surface lines (generated by default; injectable for tests).
- * @param types - the type-shape catalog (generated by default; injectable for tests).
+ * @param api - generated service entries, replaceable in tests.
+ * @param inherited - inherited `ctx` entries, replaceable in tests.
+ * @param types - public type shapes, replaceable in tests.
  * @returns the section lines.
  */
 export function describeApi(

packages/cordis/tool-cordis/src/mount.ts

@@ -21,11 +21,8 @@ export interface DynamicMount {
 }
 
 /**
- * Mount a plugin under the group fiber and settle it. The group fiber loads
- * asynchronously right after the owning plugin's `apply`, so it is awaited
- * before hanging a child off its context. The child fiber's `await()` settles
- * its lifecycle work and rethrows a startup error (e.g. a throwing `apply`);
- * on error the fiber is disposed first — a failed mount never lingers.
+ * Await the group, mount and settle one guarded child, and dispose it before rethrowing any
+ * startup failure so a failed mount never lingers. A valid unresolved inject may remain pending.
  * @param group - the `cordis-dynamic` group fiber every mount hangs under.
  * @param plugin - the plugin the sandbox returned; wrapped with the registration guard before mounting.
  * @returns the settled child fiber (possibly pending on unsatisfied `inject`).

packages/cordis/tool-cordis/src/sandbox.ts

@@ -1,20 +1,10 @@
 /**
- * The `node:vm` sandbox `cordis_mount` code evaluates in: a fresh realm whose
- * globals are a tagged write-through console, the `harness` registration
- * helpers, the encoding primitives a bare vm context lacks, and callable traps
- * over the Node APIs the sandbox deliberately withholds. Capability access is
- * routed through cordis services, never Node built-ins: filesystem work goes
- * through `ctx.fs`, network through `ctx.web`, processes through `ctx.bash`,
- * timers through the `ctx.timer` helpers (fiber effects, unwound on unmount)
- * — so a well-behaved mount stays inspectable and disposable. That routing is
- * STEERING toward the cordis services, not containment: the sandbox guards
- * against ACCIDENTAL global pollution, and it is not a security boundary. The
- * host-realm helpers on the sandbox global (`harness`, `console`, `btoa`) are
- * reachable functions, so a mount that goes looking — e.g. through such a
- * helper's `.constructor` — can still reach the host realm; that is accepted,
- * because the `ctx` a mounted plugin's `apply` later receives is the real,
- * fully privileged runtime handle, and that is the point of the toolset.
- *
+ * The `node:vm` sandbox `cordis_mount` code evaluates in: a fresh realm whose globals are a
+ * tagged write-through console, the `harness` registration helpers, the encoding primitives a
+ * bare vm context lacks, and callable traps over the Node APIs the sandbox deliberately
+ * withholds. Traps steer filesystem, network, process, and timer work to `ctx.fs`, `ctx.web`,
+ * `ctx.bash`, and Cordis timers. This keeps cooperative mounts inspectable and disposable but
+ * is not containment: host-realm helper functions remain an escape route.
  * @module @deepseek-ai/dsh-tool-cordis/sandbox
  */
 
@@ -35,17 +25,8 @@ function taggedConsole(id: string): Record<'log' | 'info' | 'warn' | 'error' | '
 }
 
 /**
- * Per-sandbox prelude: give the vm realm's own constructors a
- * `Symbol.hasInstance` that checks BOTH realms. Model code runs against a
- * fresh vm realm, but most objects it touches are HOST-realm (the `args` a
- * tool's `execute` receives, event payloads a listener observes, service
- * return values), so a plain `x instanceof Array` / `instanceof Object` in
- * sandbox code would silently be false. The patch replaces each vm
- * constructor's own `[Symbol.hasInstance]` with "ordinary check against the
- * vm constructor OR the host counterpart" — the ordinary algorithm is a pure
- * prototype-chain walk, so calling it with the host constructor as receiver
- * needs no host-side change. ONLY vm-realm globals are modified; host
- * intrinsics are passed in as values and never touched.
+ * Patch only VM constructors so `instanceof` accepts both VM values and host values passed as
+ * arguments, events, or service results; host intrinsics remain untouched.
  */
 const DUAL_REALM_INSTANCEOF_PRELUDE = `
 (hostIntrinsics) => {
@@ -156,13 +137,10 @@ export function syntaxErrorContext(error: Error): string {
 }
 
 /**
- * Evaluate mount code as the body of an async function inside the sandbox.
- * `vmTimeoutMs` only bounds the SYNCHRONOUS portion; an async body escapes it
- * — acceptable under the module's trust stance. A parse failure is answered
- * with the offending line + caret and a teaching hint: TypeScript syntax on
- * the failing line gets the remove-annotations fix, anything else gets the
- * function-body/bracket-balance reminder (models habitually close the returned
- * plugin object with `});` as if it were a callback argument).
+ * Evaluate mount code as the body of an async function inside the sandbox. `vmTimeoutMs` only
+ * bounds the SYNCHRONOUS portion; an async body escapes it — acceptable under the module's
+ * trust stance. Parse errors include the offending line and a TypeScript-removal or bracket-
+ * balance hint.
  * @param sandbox - the contextified object from {@link createSandbox}.
  * @param code - the model-written function body; must `return` a plugin.
  * @param id - the mount id, used as the vm filename (`cordis-mount-<id>.js`).

packages/cordis/tool-cordis/tests/mount.spec.ts

@@ -48,12 +48,7 @@ describe('cordis_mount', () => {
   })
 
   it('normalizes a self-made tool\'s result into the host realm, so the session log accepts it', async () => {
-    // The model's execute builds its content blocks INSIDE the vm, where
-    // Object.prototype is a different object — dsh-session's isJsonValue (the
-    // gate every `tool/result` append runs through) compares prototype
-    // IDENTITY, so a raw foreign-realm result would error the whole turn the
-    // first time the self-made tool runs. harness.defineTool round-trips the
-    // return into host-realm JSON before it reaches the registry.
+    // VM-realm objects fail the session prototype-identity check; normalize them into host JSON.
     const ctx = await setup()
     await call(ctx, 'cordis_mount', { code: REVERSE_TOOL_CODE })
     const reversed = await call(ctx, 'reverse_text', { text: 'harness' })
@@ -94,11 +89,8 @@ describe('cordis_mount', () => {
     ['object-form blocks missing the type tag', 'return { content: [{ text: \'hi\' }] }', '{"content":[{"text":"hi"}]}'],
     ['undefined — a forgotten return', 'return undefined', 'undefined'],
   ])('rejects an execute return of %s as that one call\'s teaching error', async (_label, returnStatement, preview) => {
-    // The failure this prevents: the registry trusts the return shape
-    // (postExecute spreads result.content), so an unvalidated { content: 'ok' }
-    // would enter the session log as ['o','k'] and silently corrupt the next
-    // model request. The shape check turns it into THIS call's error instead —
-    // one well-formed text block the log and the model can digest.
+    // The registry spreads result.content, so { content: 'ok' } would become ['o','k']; reject
+    // it as this call's error before it corrupts the next request.
     const ctx = await setup()
     await call(ctx, 'cordis_mount', {
       code: `
@@ -150,10 +142,8 @@ describe('cordis_mount', () => {
   })
 
   it('accepts a JSON-Schema-style parameters wrapper and normalizes it to the DSL', async () => {
-    // The dialect models write by strong prior: the { type:'object',
-    // properties, required: […] } wrapper, `type: 'integer'`, and
-    // `required: false`. All of it has exactly one meaning — normalize instead
-    // of burning a model turn on a lecture.
+    // These common JSON-Schema spellings each have one DSL meaning, so normalize rather than
+    // consume another model turn with a rejection.
     const ctx = await setup()
     const result = await call(ctx, 'cordis_mount', {
       code: `
@@ -535,10 +525,9 @@ describe('cordis_mount', () => {
   })
 
   it('makes instanceof inside the sandbox see BOTH realms (patched vm constructors, host untouched)', async () => {
-    // The args a tool's execute receives are HOST-realm objects; without the
-    // dual-realm Symbol.hasInstance prelude, `args.items instanceof Array` in
-    // sandbox code is silently false. The patch lives on the vm realm's own
-    // constructors only — the host realm's must stay pristine.
+    // The args a tool's execute receives are HOST-realm objects; without the dual-realm
+    // Symbol.hasInstance prelude, `args.items instanceof Array` in sandbox code is silently
+    // false.
     const ctx = await setup()
     await call(ctx, 'cordis_mount', {
       code: `

packages/cordis/tool-cordis/tests/sandbox-context.spec.ts

@@ -2,13 +2,10 @@ import { describe, expect, it } from 'vitest'
 import { call, setup, text } from './helpers.ts'
 
 /**
- * The sandbox context façade is a whitelist, not a pass-through proxy: mount
- * code reaches only the registration/eventing verbs, the timer helpers, a
- * guarded `tools`, and its injected services. Every framework-plumbing member
- * that could hand back an UNGUARDED context — through which a plugin could
- * `ctx.<escape>.tools.register({…})` to bypass the marker check and host-realm
- * normalization — is denied. These are the regression guards for that escape
- * class (the review finding on the original pass-through proxy).
+ * The sandbox context façade is a whitelist, not a pass-through proxy. Mounted code reaches only
+ * registration/eventing verbs, timer helpers, guarded tools, and injected services. Framework
+ * members that expose an unguarded context are denied because they could bypass marker checks and
+ * host-realm normalization; these tests pin that escape class.
  */
 
 /** Mount a plugin whose `apply` touches one framework member, and report the error text. */
@@ -77,10 +74,8 @@ describe('sandbox context façade — escape surface is closed', () => {
 
   it('denies a service whose method returns a Context (the .ctx escape), registering nothing', async () => {
     // A cordis Service instance carries `.ctx` (a real Context), so
-    // `ctx.systemPrompt.ctx.root.tools.register(…)` would be a fresh unguarded
-    // handle. The service wrapper's return-value guard rejects any Context on
-    // the way back to sandbox code, so the escape never lands. (`systemPrompt`
-    // is in the setup harness, so the plugin activates and its apply runs.)
+    // `ctx.systemPrompt.ctx.root.tools.register(…)` would escape the façade; service-return
+    // guards reject that Context before the registration lands.
     const ctx = await setup()
     const result = await call(ctx, 'cordis_mount', {
       code: `
@@ -104,10 +99,8 @@ describe('sandbox context façade — escape surface is closed', () => {
   })
 
   it('guards an async injected-service method: a host-realm Promise resolves through the guard', async () => {
-    // The return guard's Promise arm only fires for a HOST-realm Promise
-    // (a vm-realm one is not `instanceof` the host `Promise`). Provide a
-    // host-realm service from the test, then inject + await it from a mount:
-    // the resolved value is non-Context data and passes through.
+    // The return guard's Promise arm only fires for a HOST-realm Promise (a vm-realm one is not
+    // `instanceof` the host `Promise`).
     const ctx = await setup()
     ctx.plugin({
       name: 'host-async-svc',
@@ -194,11 +187,8 @@ describe('sandbox context façade — inject gate on services', () => {
   })
 
   it('a cross-mount consumer must declare the provider — the undeclared path is refused, not left as a zombie tool', async () => {
-    // The finding's scenario: a consumer registers a tool built on a provider's
-    // service WITHOUT declaring inject. cordis would then never park the
-    // consumer when the provider unmounts, leaving a tool that fails only at
-    // execution. The gate refuses the undeclared access up front, so the
-    // dependency is always visible to cordis.
+    // Without declared inject, Cordis cannot park the consumer when its provider unmounts. The
+    // façade refuses access up front instead of leaving a zombie tool.
     const ctx = await setup()
     await call(ctx, 'cordis_mount', {
       code: 'return { name: \'greeter-provider\', apply(ctx) { ctx.provide(\'greeter\', { greet: (n) => \'hi \' + n }) } }',
@@ -231,11 +221,9 @@ describe('sandbox context façade — inject gate on services', () => {
 
 describe('sandbox tools façade — get is a read-only schema view', () => {
   it('ctx.tools.get returns a schema, not the live ToolDefinition with execute', async () => {
-    // The finding: returning the raw ToolDefinition hands mount code the
-    // tool's execute function, letting it bypass ToolRegistry.execute (and its
-    // pre/post hooks). get now returns the same name/description/parameters
-    // view as schemas(), with no execute. Asserted via a self-made tool that
-    // reports the shape it saw — world-checked, not self-reported.
+    // The finding: returning the raw ToolDefinition hands mount code the tool's execute
+    // function, letting it bypass ToolRegistry.execute (and its pre/post hooks). get now
+    // returns the same name/description/parameters view as schemas(), with no execute.
     const ctx = await setup()
     await call(ctx, 'cordis_mount', {
       code: `

packages/core/agent-core/README.md

@@ -2,7 +2,7 @@
 
 The **default executor-less, UI-less agent spine** as ONE Cordis bundle plugin. It loads the fixed set of services every harness agent needs, including the local skill provider, and forwards the loop's `agents` list as its own config — so an app package composes a working agent by adding only a front door and the swappable backends.
 
-This is the package to read to see **the whole shared plugin tree at once**: the teaching overview of the spine behind every app package.
+Read this package for the whole plugin tree and its composition order.
 
 ## The tree it loads
 
@@ -47,7 +47,7 @@ The bundle FORWARDS each field to the child that owns it: `agents` to `agent-loo
 
 ## Why a code bundle, not a shared YAML include
 
-A YAML include can dedupe the config, but it cannot OWN a `bin`, and it can only *describe* the front-door coupling in a comment and trust each leaf to obey. Moving the spine into a package, and the front-door cluster into the app packages, means the default leaf for an ACP server has no logger entry to copy wrong — "the ACP app never logs to stdout" stops being a prose warning a leaf must remember and becomes the app package's default shape (a leaf can still add a sibling logger, so the rule stays documented — but it has nothing to get wrong by default). Services register in the root store keyed by their isolate symbol, so a child loaded here is visible to the bundle's siblings (the leaf's adapter and executor) exactly as a nested `plugin-include` subtree's services were — cordis gates every read on `inject`, never on load order.
+A YAML include can deduplicate config but cannot own a bin or provide front-door defaults. App packages make stdout-safe ACP wiring the default, though a leaf can still add an unsafe logger. Bundle children register services in the root isolate-keyed store, so injected leaf siblings see them without load-order coupling.
 
 ## Model Experience
 
@@ -55,6 +55,5 @@ Indirectly, through `dsh-system-prompt`, `dsh-tool-skill`, `dsh-tool-bash`, and
 
 ## Known Limitations and Deferred Work
 
-- **FIXME: package name and location imply product core** — rename `dsh-agent-core` to `dsh-demo-bundle` and move it under `packages/support/`; it is a demo composition bundle, not the product spine.
 - **The spine set is fixed in code** — `apply()` mounts every child unconditionally (including `tool-bash`); no config excludes or replaces one, so swapping the loop or dropping a spine member means composing a different bundle.
 - **`dsh-invariants` mounts unconditionally** — this bundle has no toggle, so every composition using it pays the dev-mode relational assertions; Session's always-on validation and freezing are separate.

packages/core/agent-core/src/index.ts

@@ -1,47 +1,9 @@
 /**
- * The default executor-less, UI-less agent spine as ONE bundle plugin.
- *
- * Loads the fixed set of services every harness agent needs — `timer`, the LLM
- * service, the session store, system-prompt assembly, the tool registry, the
- * skill registry plus local skill provider, the agent registry, the dev-mode
- * invariants, the model-facing `bash` and `skill` tool schemas, and the concrete `agent-loop` — and forwards the loop's `agents`
- * list as its OWN config (default `[]`), so each app supplies its own
- * pre-created agents.
- *
- * It is deliberately NOT the whole app: the swappable choices stay OUTSIDE the
- * bundle, picked by whatever loads it.
- *  - the LLM ADAPTER (`llm-deepseek`/`llm-pi-ai`/`llm-replay`) — the bundle
- *    ships the abstract `llm` service + `tool-bash` consumer schema; the leaf
- *    registers a concrete adapter on `ctx.llm`.
- *  - the bash EXECUTOR (`bash-local` or a sandboxed impl) — the bundle ships
- *    the `bash` tool consumer; the leaf provides `ctx.bash`.
- *  - the PRESENTATION (stdio UI / ACP bridge / a logger) and the per-app infra
- *    (a console logger, `hmr`) — these are the coupled "front-door cluster" the
- *    app packages ({@link @deepseek-ai/dsh-stdio-agent},
- *    {@link @deepseek-ai/dsh-acp-agent}) bake in, NOT the shared spine.
- *  - additional SKILL PROVIDERS; the bundle ships the local filesystem provider
- *    because local skills are default agent behavior, while embedded or remote
- *    providers remain deployment choices.
- *
- * This is the interface/implementation/consumer seam at the composition level:
- * the bundle owns the shared spine, the leaf owns the backends, the app package
- * owns the front door. `timer` is in the spine (common to every front door — it
- * writes nothing to stdout); the console logger is NOT (it writes to stdout,
- * which the ACP bridge reserves for its JSON-RPC channel).
- *
- * Services register in the root store keyed by their isolate symbol, so a child
- * loaded here via `ctx.plugin(...)` is visible to the bundle's SIBLINGS (the
- * leaf's adapter and executor) exactly as a nested `plugin-include` subtree's
- * services were before this bundle existed — cordis gates every read on
- * `inject`, never on load order, so the fixed child set resolves regardless of
- * which entry loads first.
- *
- * Plugin export shape: named `name`/`Config`/`apply`, NO default export — the
- * cordis Loader's `unwrapExports` does `exports.default ?? exports`, so a stray
- * default would collapse the module to the bare `apply` function and drop the
- * `Config` schema (see docs/postmortem/0001). The keyless Loader-path smokes in
- * the app packages guard this end-to-end.
- *
+ * Default executor-less, UI-less agent spine. It bundles the common services,
+ * concrete loop, local skill provider, and model-facing bash/skill consumers;
+ * deployments still choose the LLM adapter, bash executor, and presentation.
+ * The plugin intentionally exposes named exports only because Loader default
+ * unwrapping would discard its `Config` schema (see docs/postmortem/0001).
  * @module @deepseek-ai/dsh-agent-core
  */
 
@@ -73,16 +35,13 @@ export interface SkillConfig {
 }
 
 /**
- * Bundle config: each field forwarded verbatim to the child that owns it —
- * `agents` to the agent loop (an app that pre-creates no agents, like the ACP
- * bridge, simply omits it), `persona` and `toolOrder` to the system-prompt
- * plugin (the deployment's persona section and the explicit model-facing tool
- * order), the `tools` object to the tool registry (its presentation `mode`),
- * and `skills` to the skill registry/local provider/tool consumer. Every field
- * is optional INPUT here because each owner's schema supplies the default;
- * the schema is the INTERSECTION of the owners' own schemas (with registry
- * schemas nested under their bundle keys), so validation and defaulting can
- * never drift from them.
+ * Bundle config: each field forwarded verbatim to the child that owns it — `agents` to the
+ * agent loop (an app that pre-creates no agents, like the ACP bridge, omits it),
+ * `persona` and `toolOrder` to the system-prompt plugin (the deployment's persona section and
+ * the explicit model-facing tool order), the `tools` object to the tool registry (its
+ * presentation `mode`), and `skills` to the skill registry/local provider/tool consumer.
+ * The schema intersects the owners' schemas, which supply defaults for every
+ * optional input and keep validation from drifting.
  */
 export interface Config {
   /** The agent-loop `agents` list (see dsh-agent-loop's `Config`). */
@@ -124,12 +83,7 @@ export function apply(ctx: Context, config: Config): void {
   ctx.plugin(Timer)
   ctx.plugin(LlmService)
   ctx.plugin(SessionStore)
-  // The forwarded fields are validated + defaulted by this bundle's intersected
-  // schema before apply runs, so the ?? fallbacks only narrow the
-  // optional-input TYPES — they mirror the owners' schema defaults, never
-  // introduce different ones. toolOrder has no owner-supplied default value —
-  // ABSENT means "lexicographic order" — so it is forwarded conditionally
-  // rather than via ??.
+  // Owner schemas resolve defaults; forward toolOrder only when explicitly set.
   ctx.plugin(SystemPrompt, {
     persona: config.persona ?? '',
     ...config.toolOrder !== undefined ? { toolOrder: config.toolOrder } : {},

packages/core/agent-core/tests/agent-core.spec.ts

@@ -187,15 +187,8 @@ describe('dsh-agent-core bundle', () => {
   })
 
   it('has the namespace-plugin export shape (no stray default) so the Loader keeps name/Config/apply', () => {
-    // Postmortem 0001 guard: a stray `export default apply` makes the Loader's
-    // `unwrapExports` (`exports.default ?? exports`) collapse the module to the
-    // bare `apply` function, DROPPING the named `name`/`Config`. This package has
-    // no `inject` export (it mounts children that carry their own), so that
-    // collapse would NOT crash at load — the plugin would boot but silently lose
-    // its config schema. This bundle is also never Loader-unwrapped by any smoke
-    // (the apps import it directly; the mount test namespace-mounts it), so this
-    // is its ONLY export-shape guard. Assert directly AND through the real
-    // `unwrapExports` so adding `export default` to src/index.ts fails here.
+    // A default export would make `unwrapExports` collapse this inject-less namespace and silently
+    // drop `name`/`Config`. Apps import the bundle directly, so this is its Loader-shape guard.
     expect('default' in agentCore).toBe(false)
     expect(typeof agentCore.apply).toBe('function')
 

packages/core/agent-core/tests/gen-config-catalog.spec.ts

@@ -1,18 +1,5 @@
 /**
  * Negative-path tests for the config catalog generator (`scripts/gen-config-catalog.ts`).
- *
- * The generated catalog is frozen by a regenerate-and-diff freshness gate, so
- * the freshness half is exercised by `pnpm run verify-config-catalog` in CI.
- * What a freshness diff CANNOT prove is that the generator REJECTS malformed
- * source the way it promises to — an unclassifiable package, an undocumented
- * config field, a schema key the config type does not declare, or a referenced
- * type name that resolves nowhere. These tests drive `collectConfigCatalog()`
- * against synthetic fixture packages to prove each guard fires (and that
- * well-formed packages classify and extract correctly), mirroring the
- * negative tests for gen-cordis-catalog. The spec lives in this package
- * because agent-core is the config-composition plugin (its schema is the
- * intersection of its children's), the shape the generator's cross-package
- * folding exists for.
  */
 
 import { mkdtempSync, mkdirSync, rmSync, writeFileSync } from 'node:fs'

packages/core/agent-loop/README.md

@@ -1,6 +1,6 @@
 # dsh-agent-loop
 
-THE concrete agent plugin: `ReactLoopAgent` and the loop driver. Implements the `Agent` interface and drives the session/turn/step lifecycle.
+Concrete `ReactLoopAgent` implementation and loop driver.
 
 This is the only package in the harness that contains concrete loop logic. Everything else is an abstract service or a plugin against extension seams — new behavior goes into plugins, not here.
 
@@ -8,18 +8,16 @@ This is the only package in the harness that contains concrete loop logic. Every
 
 ### Public API
 
-Creation and resume are one rollback-covered transaction: construct a private session, concrete agent, and scoped context; await optional setup; enter both registries; announce `session/created` then `agent/created`; emit `agent/session-start`; and only then start the driver. Setup receives the full scoped `Context` as trusted same-process composition code and must not drive the unpublished agent. Ordinary typed identity and option inputs are borrowed under their readonly contract, while seed events and session metadata are validated and snapshotted because they cross the durable session boundary. An optional `AbortSignal` cancels only load/setup/publication and is detached before the returned handle becomes visible.
+Creation and resume use one caller-owned transaction: compose while unpublished, enter both registries, announce lifecycle edges, then start the driver. Failure rolls back private resources; caller, handle, and provider teardown share one quiescence boundary. The interface contract and ownership order live in [`dsh-agent`](../agent/README.md) and the [agent-scope runtime RFC](../../../docs/rfc/implemented/architecture/2026-07-12-agent-scope-runtime-design.md).
 
-The caller fiber and the AgentLoop provider are co-owners. `AgentFactory.createAgent(ownerCtx, options)` and `resume(ownerCtx, options)` receive caller ownership explicitly, while the factory keeps its own dependency context for `sessions`/`llm`/`tools`/`systemPrompt`; this lets a caller inject only `agents` without shrinking the new agent's service surface. Caller unload, handle disposal, or provider unload converge on one memoized quiescence boundary. Provider shutdown waits both resource teardown and the public create/resume wrapper that observed deactivation, so no continuation can publish after dependencies disappear.
+Caller-chosen ids arbitrate only at final registry entry, so concurrent contenders may prepare but every loser rolls back. Entry-bound detach capabilities cannot remove a later same-id replacement. Teardown stops and drains—including idle-injection flushes—before detaching agent, session, and scope; ids become reusable at detach.
 
-IDs are caller-chosen and assumed globally unique; accidental UUID collisions are outside the supported model. Two concurrent operations with the same agent or session id may both prepare, but the final `enter()` calls arbitrate publication and every loser rolls its private resources back. Each detach is bound to the exact entered object, so a stale disposer cannot remove a later same-id replacement. A detach requested during a synchronous creation notification waits for that dispatch to unwind, preserving created/disposed pairing. Teardown runs stop and drain (including outstanding idle-injection flushes) → detach agent → detach session → unwind scope; IDs become reusable at detach even if private scope cleanup is still finishing. Ordinary non-vetoing `agent/*` notifications go through `agentEvents(ctx, agent)`, per-step assembly goes through `assembleContextFor(agent)`, and turn-end durability checkpoints go through `ctx.sessions.flush(session)`.
-
-- `ctx.agentLoop.create(id: string, options?: AgentOptions, meta?: { cwd?: string }): ReactLoopAgent` — synchronous no-setup create, used directly by programs and by `cordis.yml`-configured agents. It creates a fresh per-run session id `${id}-session-<uuid>` with optional metadata; the uuid avoids colliding with a prior durable log. Each call is a new session (a deliberate demo simplification — a real resume-or-create policy is a TODO). Disposed with the calling fiber.
+- `ctx.agentLoop.create(id, options?, meta?)` synchronously creates a caller-fiber-owned agent with a fresh generated session id and optional cwd. Each call starts a new session rather than applying resume-or-create policy.
 
 `AgentLoop` also implements the `AgentFactory` seam and registers itself via `ctx.agents.setFactory(this)`, so plugins create/resume agents through `ctx.agents` (the interface):
 
-- `ctx.agents.create({ agentId, sessionId, meta?, seed?, agentOptions?, setup?, signal? }): Promise<AgentHandle>` — programmatic create on a caller-supplied `sessionId`, NOT `${id}-session`. It awaits the unpublished setup transaction before returning; `meta` carries cwd/lineage/seed-boundary metadata and `seed` reconstructs a forked child prefix after the session boundary validates and snapshots the durable values. `signal` applies only until this promise settles. The resolved [`AgentHandle`](../agent/README.md) owns exact teardown.
-- `ctx.agents.resume({ agentId, resumeSessionId, agentOptions?, setup?, signal? }): Promise<AgentHandle>` — load a persisted session via `ctx.sessionPersistence` ([session persistence](../../../docs/rfc/implemented/architecture/2026-06-14-session-persistence.md)), reconstruct its history, then await setup against a fresh unpublished agent scope before rollback-covered publication. The live session id is the resumed id; turn numbering and derived history continue from the loaded log. Requires a session-persistence backend (NOT hard-injected — non-persistent demos still work; `resume` rejects with a clear error when persistence is absent). `signal` is creation-only. Returns an `AgentHandle`.
+- `ctx.agents.create({ agentId, sessionId, meta?, seed?, agentOptions?, setup?, signal? })` validates and snapshots durable seed and metadata, awaits optional composition while unpublished, creates on the supplied session id, and returns an owned [`AgentHandle`](../agent/README.md). Its signal applies only until publication.
+- `ctx.agents.resume({ agentId, resumeSessionId, agentOptions?, setup?, signal? })` loads through optional [session persistence](../../../docs/rfc/implemented/architecture/2026-06-14-session-persistence.md), continues stored history and turn numbering under the resumed session id, and follows the same unpublished setup and creation-only cancellation boundary. It rejects when no persistence backend is mounted.
 
 The config-driven `ctx.agentLoop.create()` path keeps its agent owned by the loop fiber (it discards the handle). For a programmatic agent, the handle holder is the only consumer-facing teardown capability; AgentLoop provider unload is the independent structural teardown edge, not another handle exposed to application code.
 
@@ -40,7 +38,7 @@ interface Config {
 }
 ```
 
-Agents listed in config are auto-created at startup. `cwd` applies only to fresh config-created sessions; `resumeSessionId` keeps the persisted session header. Config agents have no per-agent persona field: they use `dsh-system-prompt`'s deployment default, while programmatic factory callers can register an agent-scoped `deployment:persona` shadow in `setup`. The plugin registers the built-in `model`/`cwd` prompt variables on `ctx.systemPrompt`, resolved per step from `assembleContextFor(agent)` — the helper couples the typed agent with its matching scope selector. These are runtime facts of the agents THIS loop drives, unlike the `harness:identity` and default `deployment:persona` sections, which live on `dsh-system-prompt` so they survive a swapped loop plugin.
+Configured agents start automatically. `cwd` applies only to fresh sessions; `resumeSessionId` retains persisted metadata. They use the deployment persona. Programmatic setup can shadow it per agent. This plugin supplies the per-agent `model` and `cwd` prompt variables; harness identity and deployment persona belong to `dsh-system-prompt`.
 
 ### Exported concrete class
 
@@ -50,53 +48,9 @@ Agents listed in config are auto-created at startup. `cwd` applies only to fresh
 
 ### Loop lifecycle (`loop.ts`)
 
-The internal loop driver runs one agent for its whole lifetime:
+The driver owns one agent for its lifetime. It records turn, step, request, stream, and tool boundaries in the session log; live extension events coordinate policy around those durable facts. The [architecture turn flow](../../../docs/architecture.md#turn-flow) and generated [event catalog](../../../docs/cordis-catalog/events.md) are the authoritative sequence and signatures.
 
-```
-create agent → emit agent/session-start(source)   ⟵ once, before turn 1
-forever:
-  wait for queued messages (idle)
-  TURN (error-contained):
-    'turn/start'
-    each queued: waterfall agent/prompt-submit → allow (→ session('user/message'),
-      inject additionalContext) | block (→ session('prompt/blocked'), drop)
-    if every prompt blocked: 'turn/end'(rejected), no step  ⟵ zero-step turn
-    STEP loop:
-      drain steering
-      assembly = await systemPrompt.assemble(assembleContextFor(agent))
-                                                ⟵ renderPrompt(assembly) IS the full prompt
-      prefix ??= waterfall agent/session-prefix   ⟵ once per instance (first step): frozen
-                                                session prefix; on the header, never history
-      await serial agent/pre-step(…, prefix)  ⟵ surface mutation (compaction) outside the step;
-                                                pressure gates see the prefix the request carries
-      boundary = session.deriveMessages()   ⟵ reconstruction boundary: same sync frame,
-      session('step/start')                     strictly before step/start
-      config = waterfall agent/request       ⟵ frozen seed; return a replacement to switch
-      session('request/header'[-delta])      ⟵ the header event this request owes the log
-      stream llm.stream(freeze({header..., messages: prefix+boundary})) → session('assistant/chunk')
-      message = waterfall agent/step-result
-      session('assistant/message')
-      each tool-call: session('tool/call')
-        → tools.execute() [pre waterfall → monotonic guards → around dispatch → post waterfall → final notification]
-        → session('tool/result')
-      append buffered post-execute additionalContext as session('context/message')(s)
-      drain steering → session('steering/message')
-      cont = waterfall agent/turn-continuation → ContinuationDecision
-        ({action:'continue', reason?} records reason as next-step steering)
-      pending steering can override an ordinary stop
-      terminal = serial agent/turn-stop → ContinuationStop | undefined
-        (after ordinary decision/reason/steering folding)
-      if terminal stop, or ordinary action==stop with no pending steering: break
-    session('turn/end')
-    await session/flush
-    terminal turn: discard steering added before/during close and flush; keep ordinary queued sends
-    ordinary turn: re-enqueue leftover steering as queued
-  idle unless more queued
-```
-
-Error containment: a throwing plugin ends the **turn**, never the loop. A throwing `agent/turn-stop` policy likewise fails the turn closed. A successful terminal stop stays authoritative through `turn/end` and `session/flush`, preventing their listeners from resurrecting steering through the late fallback. Dispose mid-turn emits `agent/status('disposed')` and ends with reason `disposed`. A step that hits the model's output-token ceiling makes the turn end `max-tokens` (the rule: any `max-tokens` step in the turn surfaces as `max-tokens`; `disposed`/`aborted`/`error` still take precedence) — distinct from a clean `completed` stop.
-
-Cancellation: `agent.cancel()` is the single public stop primitive — it clears the queued + steering FIFOs, aborts the in-flight step, and drives a turn-scoped marker the driver checks at every point a turn could start or continue (right after the idle wait, after the `running` flip, before each step, and at the continuation gate) so a turn about to start is dropped. A cancelled turn ends `aborted`; a queued-but-not-started prompt never runs and cannot be batched into the cancelled turn. The marker is reset once per loop iteration, so a cancel governs exactly one turn and never leaks onto a later prompt. (The loop still aborts its own per-step `AbortController` directly on disposal and from `cancel()`; that controller is loop-internal, not a public verb.)
+Plugin failure ends the current turn, not the loop. Cancellation clears pending work and aborts the current step without leaking to the next prompt. Terminal continuation stops remain authoritative through turn close and durability flush.
 
 ### What belongs to plugins
 
@@ -128,4 +82,3 @@ Everything that goes beyond "call the model, run the tools, repeat" belongs to p
 - **No resume-or-create policy on the config path** — config-driven `create()` starts a fresh `${id}-session-<uuid>` every run (`TODO(demo)`), and a config `resumeSessionId` whose resume fails logs a warning and creates no agent.
 - **Config agents have no per-agent persona field or setup hook** — they use the deployment persona; scoped persona/tool composition is available only through the programmatic `ctx.agents.create()` / `resume()` factory options.
 - **No built-in turn budget** — the default continuation is `continue` whenever a step had tool calls or steering; bounding a runaway turn requires an `agent/turn-continuation` force-stop plugin.
-- **`runLoop`/`Inbox`/`InboxMessage` stay exported with no outside consumer** — [removal is proposed](../../../docs/rfc/proposed/simplification/2026-07-04-prune-dead-core-spine-surface.md).

packages/core/agent-loop/src/agent.ts

@@ -48,10 +48,8 @@ export interface PreparedReactLoopAgent {
 }
 
 /**
- * Construct one concrete agent together with unforgeable, instance-bound
- * lifecycle controls. The package surface deliberately exposes neither source
- * subpaths nor this helper: setup code may identify the concrete class, but it
- * cannot publish or start the factory's unpublished instance.
+ * Construct an unpublished concrete agent with instance-bound lifecycle
+ * controls. Only those paired controls can publish or start this instance.
  * @param ctx - the agent-loop service context used for driving and events.
  * @param id - the concrete agent identity.
  * @param options - loop options for the agent.
@@ -131,16 +129,7 @@ export class ReactLoopAgent implements Agent {
    * leave it set to wrongly drop a later prompt.
    */
   private cancelRequested = false
-  /**
-   * The resolved reason for the pending {@link cancel} (`reason ?? 'cancelled'`),
-   * read by the driver loop's marker branches so a turn dropped in a
-   * marker-only window (pre-step / continuation, where no `AbortController`
-   * carries the reason) ends with the SAME `{kind:'aborted', reason}` the
-   * mid-step abort path produces from `abort.signal.reason`. Without this the
-   * caller's `cancel(reason)` would be silently replaced by the literal
-   * 'cancelled' whenever the cancel landed outside a running step — making the
-   * logged reason race-dependent and the public `reason?` param half-effective.
-   */
+  /** Pending cancellation reason, preserved even outside an active step signal. */
   private cancelReason = 'cancelled'
   private disposed: Promise<void>
   private resolveDisposed!: () => void
@@ -179,11 +168,7 @@ export class ReactLoopAgent implements Agent {
   private setStatus(status: AgentStatus): void {
     if (this._status === status || this._status === 'disposed') return
     this._status = status
-    // Release quiescence waiters on a transition OUT of running BEFORE emitting
-    // (the disposer handles the disposed transition separately). Settling first
-    // means a throwing `agent/status` subscriber cannot starve a `whenIdle()`
-    // waiter (docs/defensive-patterns.md "contain callback exceptions" — a lifecycle await must
-    // not hang on one bad listener).
+    // Settle first so a throwing status listener cannot starve quiescence waiters.
     if (status !== 'running') this.settleIdleWaiters()
     agentEvents(this.loopCtx, this).emit('agent/status', status)
   }
@@ -269,18 +254,8 @@ export class ReactLoopAgent implements Agent {
       // Decide the durability checkpoint from the log: an accepted one-shot
       // turn must be flushed even when its message append was the failing step.
       const turnRecorded = this.session.events.some(e => e.type === 'turn/start' && e.data.turn === turn)
-      // Checkpoint the one-shot turn for durability, exactly as the loop does at
-      // every turn/end. The loop is NOT running (we are idle), so nothing else
-      // will flush this turn. Fire-and-forget with error containment: inject()
-      // is synchronous, and a persistence backend failing must not throw into
-      // the caller (e.g. a tool-bash task-done callback). Disposal still drains
-      // independently, so a slow flush is safe. The task is tracked until it
-      // settles: driver disposal awaits every pending idle-injection checkpoint
-      // before unregistering the agent or detaching the session. A flush failure
-      // is reported via agent/error (step 0 — the idle-injection convention,
-      // there is no real step) AND the logger, mirroring the loop's post-turn/end
-      // flush path so plugins monitoring agent/error see idle-injection
-      // persistence failures too. A throwing agent/error listener is contained.
+      // Keep inject() synchronous: report checkpoint failures live instead of
+      // rejecting the caller, and track the task so disposal still drains it.
       if (turnRecorded) {
         // Through the store's flush (the carrier owner), never a raw parallel.
         const flush = this.loopCtx.sessions.flush(this.session).catch((error: unknown) => {
@@ -290,10 +265,7 @@ export class ReactLoopAgent implements Agent {
           agentEvents(this.loopCtx, this).emit('agent/error', turn, 0, err)
         })
         this.pendingIdleFlushes.add(flush)
-        // Attach the same retirement callback to both settlement arms so even a
-        // logger failure in the catch above cannot become an unhandled rejection.
-        // Teardown uses allSettled for the same reason: a reporting failure must
-        // not strand ownership.
+        // Retire on either settlement path.
         const retire = (): void => { this.pendingIdleFlushes.delete(flush) }
         void flush.then(retire, retire)
       }
@@ -301,15 +273,7 @@ export class ReactLoopAgent implements Agent {
   }
 
   cancel(reason?: string): void {
-    // Arm-gate: only mark a cancellation when there is actually work to cancel —
-    // a running turn, an in-flight step, or queued/steering work. An idle cancel
-    // with nothing pending is a true no-op; arming the marker then would wrongly
-    // drop the NEXT legitimate prompt (the marker is consumed only at the loop's
-    // turn-decision points, which an idle parked loop does not reach until woken
-    // by a real send()). Note the gate canNOT be `status === 'running'` alone:
-    // the pre-step window (a send() queued but the loop not yet flipped to
-    // running) has status `idle` with `hasQueued` true, and the marker exists
-    // precisely to cover it.
+    // Arm only for current work; an idle marker would cancel the next prompt.
     if (this._status === 'running' || this.currentAbort !== undefined || this.#inbox.hasQueued || this.#inbox.hasSteering) {
       this.cancelRequested = true
       // Capture the resolved reason for the marker-only windows (pre-step /
@@ -329,29 +293,14 @@ export class ReactLoopAgent implements Agent {
   }
 
   /**
-   * Resolve once the agent has reached quiescence after settling out of
-   * `running`. If it is already disposed, awaits {@link done} (the loop-exit
-   * promise) — `agent/status('disposed')` fires in the disposer BEFORE the
-   * driver loop has unwound, so it is NOT itself a quiescence signal. If it is
-   * idle AND has no queued work, resolves immediately. Otherwise queues an
-   * internal waiter (see {@link idleWaiters}) released on the next
-   * running→idle/disposed transition, resolving on `idle` directly (the turn
-   * fully ended) or chaining {@link done} on `disposed` (wait for the loop to
-   * actually exit). Implements the {@link Agent.whenIdle} contract: a non-owner
-   * quiescence-observation hook, distinct from teardown (a lifecycle owner stops
-   * and unregisters via `AgentHandle.dispose()`, whose driver boundary awaits
-   * both {@link done} and outstanding idle-injection flushes, not through this).
+   * Resolve immediately when idle with no queued work, on the next quiescent
+   * idle transition otherwise, or after driver exit when already disposed.
+   * This observes quiescence; it does not own teardown.
    */
   whenIdle(): Promise<void> {
     if (this._status === 'disposed') return this.done
     if (this._status !== 'running' && !this.#inbox.hasQueued) return Promise.resolve()
-    // Register an internal waiter (resolved by settleIdleWaiters on the next
-    // running→idle/disposed transition), NOT an effect-scoped `ctx.on` listener:
-    // a concurrent fiber disposal runs this agent's listener disposers, which
-    // could remove a `ctx.on` waiter before the `disposed` transition fires and
-    // hang the promise. On disposal the disposer settles the waiter AND we chain
-    // `done` here for true loop-exit quiescence (status flips to disposed before
-    // the loop unwinds); a plain idle transition resolves directly.
+    // Agent-owned waiters survive concurrent fiber disposal.
     return new Promise<void>((resolve) => {
       this.idleWaiters.push(() => {
         resolve(this._status === 'disposed' ? this.done : undefined)
@@ -387,12 +336,7 @@ export class ReactLoopAgent implements Agent {
       isCancelled: () => this.cancelRequested,
       cancelReason: () => this.cancelReason,
       clearCancel: () => { this.cancelRequested = false },
-      // Settle whenIdle() waiters WITHOUT a status transition — the pre-step
-      // cancel-skip path drops the about-to-run turn and re-parks without ever
-      // flipping running→idle, so a waiter registered in the pre-step window
-      // (status idle, hasQueued was true) would otherwise hang. This emits no
-      // agent/status, so an ACP agent/status listener never sees a spurious idle
-      // that would resolve a freshly-queued prompt as cancelled.
+      // Pre-step cancellation re-parks without emitting a status transition.
       settleIdle: () => { this.settleIdleWaiters() },
     })
   }
@@ -432,11 +376,8 @@ export class ReactLoopAgent implements Agent {
     // cleanup. The normal loop contains turn failures itself; allSettled is the
     // final lifecycle backstop for anything outside those boundaries.
     await Promise.allSettled([this.done])
-    // No new inject() can start after the synchronous disposed transition.
-    // Loop because settled tasks retire themselves in promise reactions that
-    // may run beside this continuation; either the set is empty or this waits
-    // the exact remaining quiescence boundary. allSettled keeps a failure in
-    // error reporting from skipping registry/session/scope disposers.
+    // Repeat because settled flushes retire in adjacent promise reactions;
+    // allSettled keeps reporting failures from skipping ownership teardown.
     while (this.pendingIdleFlushes.size > 0) {
       await Promise.allSettled([...this.pendingIdleFlushes])
     }

packages/core/agent-loop/src/index.ts

@@ -74,12 +74,9 @@ function signalAbortError(id: AgentId, signal: AbortSignal): Error {
 }
 
 /**
- * One create/resume transaction from caller ownership through unpublished
- * setup, rollback-covered publication, and final quiescent teardown.
- *
- * The class deliberately owns the state machine in one place. Registries only
- * arbitrate identity at their final `enter()` calls; before that point every
- * resource is private to this transaction.
+ * Caller-owned create/resume transaction through rollback-covered publication
+ * and quiescent teardown. Resources remain private until the final registry
+ * entry arbitrates identity.
  */
 class AgentCreationTransaction {
   private active = true

packages/core/agent-loop/src/loop.ts

@@ -1,9 +1,7 @@
 /**
- * The agent loop driver: one `runLoop()` invocation drives one agent for its
- * whole lifetime. Error-contained at the turn level — a throwing plugin ends
- * the turn, never kills the loop. See the JSDoc on `runLoop()` for the full
- * lifecycle pseudo-code.
- *
+ * Drives one agent across queued durable turns. Turn failures are contained so
+ * later work can run; the session log, not this driver, owns conversation state.
+ * See docs/rfc/implemented/architecture/2026-06-18-agent-lifecycle-and-ownership-seams.md.
  * @module dsh-agent-loop/loop
  */
 
@@ -25,33 +23,12 @@ import type { Inbox } from './inbox.ts'
 /** An Error with an optional machine-readable code (e.g., from LlmError or a throwing plugin). */
 type CodedError = Error & { code?: string }
 
-/**
- * Normalize an arbitrary thrown value into a coded Error. A real Error passes
- * through (its `code`, if any, is preserved by {@link errorData}); a non-Error
- * throw is wrapped in a {@link HarnessError} with code `UNKNOWN` and the
- * original value chained as `cause`, so a bad throw still carries a routable
- * code instead of degrading to a bare message.
- */
+/** Normalize thrown values while preserving an existing error code. */
 function toError(error: unknown): CodedError {
   return error instanceof Error ? error : new HarnessError(String(error), 'UNKNOWN', { cause: error })
 }
 
-/**
- * Map a model-call {@link FinishReason} to the step error it should raise, or
- * `undefined` when the step completed normally.
- *
- * Adapters report provider/transport failures one of two sanctioned ways (see
- * the StreamChunk contract in dsh-llm): throw from `stream()` (handled by the
- * caller's try/catch), OR end the stream with a finish-error/aborted chunk
- * (the only option for adapters that can't throw mid-stream, e.g.
- * library-backed ones). This translates the latter into a thrown step error
- * so the turn ends error/aborted (the failure recorded on `turn/end.reason`),
- * never as a normal `completed` assistant message.
- *
- * `FinishReason` is merge-extensible (plugins/adapters can add `kind`s), so
- * the switch handles the known terminal-failure kinds and treats every other
- * kind — `stop`, `tool-calls`, `max-tokens`, future additions — as success.
- */
+/** Convert terminal failure finishes into step errors; unknown extensible finishes remain successful. */
 function finishError(finish: FinishReason): CodedError | undefined {
   switch (finish.kind) {
     case 'error': {
@@ -78,19 +55,7 @@ function errorData(err: CodedError): { message: string; code?: string } {
   return { message: err.message, ...typeof err.code === 'string' ? { code: err.code } : {} }
 }
 
-/**
- * The turn-end contribution of a step's *successful* finish, or `undefined`
- * when the step finished ordinarily (a plain `completed`).
- *
- * {@link finishError} has already converted `error`/`aborted` finishes into
- * thrown step errors, so the finishes that reach here are `stop`,
- * `tool-calls`, `max-tokens`, or a future merge-extensible kind. Only
- * `max-tokens` carries forward as a distinct {@link TurnEndReason}: a step that
- * hit the output-token ceiling ended the turn cut-short rather than by the
- * model's choice. `stop`/`tool-calls`/unknown kinds contribute nothing beyond
- * the default `completed`. {@link runTurn} applies this with the rule "any
- * `max-tokens` step in the turn makes the turn end `max-tokens`".
- */
+/** Map a successful max-token finish onto the turn reason; other successful finishes add nothing. */
 function stepFinishReason(finish: FinishReason): TurnEndReason | undefined {
   switch (finish.kind) {
     case 'max-tokens':
@@ -103,11 +68,7 @@ function stepFinishReason(finish: FinishReason): TurnEndReason | undefined {
   }
 }
 
-/**
- * Ambient handles the loop driver receives from the agent. Decouples the
- * pure function `runLoop` from the mutable ReactLoopAgent fields, making the
- * loop testable without a real agent.
- */
+/** Mutable agent controls supplied to the loop driver. */
 export interface LoopHandle {
   /** Native-private agent inbox handed to the driver only at internal startup. */
   readonly inbox: Inbox
@@ -116,122 +77,37 @@ export interface LoopHandle {
   /** Resolves when the agent is disposed — unblocks the idle wait. */
   disposed: Promise<void>
   isDisposed(): boolean
-  /**
-   * Whether a `cancel()` is pending for the current turn. The driver checks this
-   * at every decision point where a turn could start or continue (right after
-   * the idle wait, after the `running` flip, before each step, and at the
-   * continuation gate) and drops the about-to-run / continuing turn. Reset once
-   * per loop iteration via {@link clearCancel} after the turn returns, so the
-   * marker governs exactly one cancellation and never leaks to a later prompt.
-   */
+  /** Whether cancellation is pending for the current loop iteration. */
   isCancelled(): boolean
-  /**
-   * The resolved reason for the pending cancel (`reason ?? 'cancelled'`), read
-   * by the marker branches (pre-step / continuation) so a turn dropped where no
-   * `AbortController` carries the reason still records the caller's
-   * `cancel(reason)` value — matching the mid-step abort path. Only meaningful
-   * when {@link isCancelled} is true.
-   */
+  /** Resolved pending-cancellation reason; meaningful only while {@link isCancelled} is true. */
   cancelReason(): string
   /** Clear the cancel marker (called once per iteration after the turn returns). */
   clearCancel(): void
-  /**
-   * Settle pending `whenIdle()` waiters WITHOUT a status transition. Used by the
-   * pre-step cancel-skip path: it drops the about-to-run turn and re-parks at the
-   * idle wait, so no `running→idle` transition fires to settle a `whenIdle()`
-   * waiter that was registered in the pre-step window — this settles it directly
-   * (it emits no `agent/status`, so an ACP `agent/status` listener never sees a
-   * spurious idle that would resolve a freshly-queued prompt as cancelled).
-   */
+  /** Settle idle waiters when pre-running cancellation skips a turn, without emitting `agent/status`. */
   settleIdle(): void
 }
 
 /**
- * The agent loop. One invocation drives one agent for its whole lifetime:
- *
- * ```
- * create agent → emit agent/session-start(source)    ⟵ once, before turn 1
- * forever:
- *   wait for queued messages (idle)
- *   TURN (error-contained — a throwing plugin ends the turn, never the loop):
- *     'turn/start'; each queued msg: waterfall agent/prompt-submit    ⟵ durable turn boundary (no agent/* mirror)
- *       allow → session('user/message'…) (+ inject additionalContext) | block → drop
- *     every prompt blocked → 'turn/end'(rejected), 0 steps
- *     STEP loop:
- *       drain steering → session('steering/message')  ⟵ catches late steering
- *       assembly = ctx.systemPrompt.assemble(assembleContextFor(agent)) ⟵ waterfall system-prompt/assemble
- *                                                        (scope-filtered; scoped sections/tools join); renderPrompt
- *                                                        (persona section + {{variables}}) IS the full prompt
- *       prefix ??= waterfall agent/session-prefix    ⟵ once per loop instance (first step): frozen
- *                                                        session prefix; logged on the header, never
- *                                                        session history (scope-filtered, fused dispatch)
- *       await events.serial('agent/pre-step', …, prefix) ⟵ surface mutation (compaction) OUTSIDE the step;
- *                                                        pressure gates see the prefix the request carries
- *       boundary = session.deriveMessages()           ⟵ the reconstruction boundary: snapshot in the
- *       session('step/start')                            same sync frame, strictly before step/start
- *       config = waterfall agent/request(config)      ⟵ frozen seed; a returned replacement switches
- *       session('request/header'|'request/header-delta')  ⟵ the header event this request owes the
- *                                                        log (initial/resume anchor, delta, fallback)
- *       req = freeze({header..., messages: prefix+boundary, sessionId, signal})
- *       stream ctx.llm.stream(req)                    ⟵ waterfall llm/stream (raw chunks, frozen req)
- *         session('assistant/chunk')
- *       msg = waterfall agent/step-result             ⟵ BEFORE the log append, so the
- *       session('assistant/message' {content, usage?})   session records what actually ran
- *       each tool-call in msg (sequential, abort-checked):
- *         session('tool/call'); ctx.tools.execute()   ⟵ tools/pre-execute (allow/deny/ask)
- *                                                        → dispatch → tools/post-execute
- *         session('tool/result')
- *       append buffered post-execute additionalContext → session('context/message')(s)
- *       drain steering → session('steering/message')
- *       session('step/end')                           ⟵ durable step boundary (no agent/* mirror)
- *       cont = waterfall agent/turn-continuation       ⟵ ContinuationDecision; default
- *         {action: hadToolCalls||steered ? 'continue':'stop'}; a continue.reason is
- *         recorded as next-step steering
- *       if action==stop && steering arrived (step/end/continuation listeners): continue anyway
- *       terminal = serial agent/turn-stop              ⟵ stop or abstain; after all ordinary
- *                                                        continuation and steering folding
- *       if terminal: discard pending steering and break
- *       if action==stop: break
- *     session('turn/end')                             ⟵ durable turn boundary (no agent/* mirror)
- *     await ctx.sessions.flush(session)               ⟵ durability checkpoint (store-owned carrier)
- *     re-enqueue leftover steering as queued          ⟵ steering is never stranded
- *   idle (emit agent/status) unless more queued
- * ```
+ * Drive queued batches as durable turns until disposal. Plugin failures end the
+ * current turn without terminating the driver.
  * @param ctx - the plugin context the loop reaches events (agent/…, session/flush) and services (systemPrompt, llm, tools) through.
  * @param agent - the agent this invocation drives for its whole lifetime (its inbox, session, and options).
  * @param handle - the bridge to the agent's mutable state: status/abort setters plus the disposal and cancel-marker reads.
  */
 export async function runLoop(ctx: Context, agent: ReactLoopAgent, handle: LoopHandle): Promise<void> {
-  // Per-instance transmission bookkeeping: whether THIS loop instance has
-  // anchored the log's header fold yet (its first request logs a
-  // 'initial'/'resume' request/header snapshot). Everything else the request
-  // needs is read from the session log itself — the loop holds no
-  // conversation state (the reconstructability RFC).
+  // Per-instance prefix and request-header state; conversation history remains in the session log.
   const transmission = createTransmissionLog()
 
   const { session } = agent
-  // The fused agent-subject dispatcher: every agent/* dispatch below carries
-  // the agent's scope (an `agent.ctx` listener hears only this agent) with
-  // the subject injected — one spelling, checked by the dev invariants.
+  // Fused subject and scope carrier for every agent event below.
   const events = agentEvents(ctx, agent)
 
   while (!handle.isDisposed()) {
     await handle.inbox.waitForQueued(handle.disposed)
     if (handle.isDisposed()) break
 
-    // Pre-step cancel (window 1): a `cancel()` landed after a `send()` woke the
-    // idle wait but before we flip to `running`. The cancelled queued/steering
-    // work is already cleared by `cancel()`. Clear the marker, then:
-    //   - if NOTHING new is queued, drop the about-to-run turn and re-park,
-    //     settling any `whenIdle()` waiter DIRECTLY (no running→idle transition
-    //     fires here to settle it) and WITHOUT emitting `agent/status` (an ACP
-    //     listener must not see a spurious idle that resolves a freshly-queued
-    //     prompt as cancelled);
-    //   - if a NEW prompt was queued AFTER the cancel (a send() that raced in
-    //     before the loop resumed), the marker was for the cancelled work only —
-    //     fall through and run the new prompt's turn. Do NOT settle waiters here:
-    //     a whenIdle() waiter must wait for that new turn's running→idle, not
-    //     resolve before it runs (the quiescence contract).
+    // Cancellation between wake and `running` skips only the cancelled work;
+    // a replacement prompt still runs and owns the eventual idle transition.
     if (handle.isCancelled()) {
       handle.clearCancel()
       if (!handle.inbox.hasQueued) {
@@ -242,18 +118,8 @@ export async function runLoop(ctx: Context, agent: ReactLoopAgent, handle: LoopH
 
     handle.setStatus('running')
 
-    // Pre-step cancel (window 2): `setStatus('running')` emits `agent/status`
-    // SYNCHRONOUSLY, so a `running` listener can `cancel()` in the gap between the
-    // check above and `runTurn`. Mirror window 1: clear the marker, then
-    //   - if NOTHING new is queued, drop the about-to-run turn and transition
-    //     back to `idle` (`running` was already emitted, so a real idle
-    //     transition balances the status AND settles `whenIdle()` waiters);
-    //   - if a NEW prompt was queued AFTER the cancel (a `running` listener that
-    //     cancels then sends), the marker was for the cancelled work only — fall
-    //     through and run the new prompt's turn (status is already `running`), so
-    //     a `whenIdle()` waiter resolves on THAT turn's running→idle, not before
-    //     it runs. Settling here would resolve quiescence while the replacement
-    //     is still queued and unrun (the same early-resolve race window 1 fixes).
+    // A synchronous `running` listener can cancel before `runTurn`; balance the
+    // status only when no replacement prompt was queued by that listener.
     if (handle.isCancelled()) {
       handle.clearCancel()
       if (!handle.inbox.hasQueued) {
@@ -262,24 +128,13 @@ export async function runLoop(ctx: Context, agent: ReactLoopAgent, handle: LoopH
       }
     }
 
-    // Re-derive the turn number from the log each iteration (do NOT keep a local
-    // counter): an idle `agent.inject()` can append its own one-shot turn while
-    // the loop waits above, so the next real turn must continue from whatever
-    // turn number is actually last in the log — a stale counter would collide.
+    // Idle injection can add a turn, so derive the next number from the log.
     const turn = lastTurnNumber(session) + 1
     let terminalStopped = false
     try {
       terminalStopped = await runTurn(ctx, events, agent, handle, turn, transmission)
     } catch (error: unknown) {
-      // Backstop: runTurn rethrows only a PRE-turn throw (the invariant guard
-      // before turn/start) — no turn/start was appended, so no turn is open and
-      // none is owed. A session `error` here would land outside any turn (after
-      // the previous turn/end), where the persistence backend drops it as a
-      // crash tail (the turn-enclosure RFC). Report via agent/error + the logger only; the
-      // driver survives and moves on.
-      // Acceptance and internal dispatch validation can reject before
-      // turn/start commits. Report that supported pre-turn failure without
-      // inventing a turn/end for a turn that never opened.
+      // Pre-turn failure has no durable boundary to close; report it without appending outside a turn.
       const err = toError(error)
       ctx.logger.warn(`agent "${agent.id}": turn ${turn} failed before it started: ${err.message}`)
       try {
@@ -287,21 +142,10 @@ export async function runLoop(ctx: Context, agent: ReactLoopAgent, handle: LoopH
       } catch { /* contained: a throwing agent/error listener must not kill the driver */ }
     }
 
-    // Reset the cancel marker UNCONDITIONALLY here, after the turn returns and
-    // before the next iteration's idle wait. NOT gated on the idle transition
-    // below: a `send()` that lands during the cancelled turn's flush window makes
-    // `hasQueued` true at the `setStatus('idle')` guard, so an idle-gated reset
-    // would never fire and the stale marker would wrongly drop that next prompt's
-    // turn. Resetting per iteration scopes the marker to exactly the turn that was
-    // cancelled.
+    // Reset per iteration, including when a prompt arrives during the flush window.
     handle.clearCancel()
 
-    // Steering that arrived too late to join an ordinary turn (turn-end
-    // listeners, flush) becomes queued input so it is never stranded. A
-    // terminal-stop owner is the deliberate exception: discard the steering
-    // again after the close + flush window so terminal policy cannot be undone
-    // after its in-turn drain. Ordinary queued sends live in a separate FIFO and
-    // remain untouched.
+    // Late steering becomes queued input unless terminal policy stopped the turn.
     for (const message of handle.inbox.drainSteering()) {
       if (!terminalStopped) handle.inbox.enqueue(message)
     }
@@ -315,10 +159,7 @@ async function runTurn(
 ): Promise<boolean> {
   const { session } = agent
 
-  // --- Pre-turn. A throw here (the invariant guard) is owed NO turn/end —
-  // turn/start has not been appended — so it propagates to runLoop's backstop
-  // untouched. The queued messages are drained here but appended AFTER
-  // turn/start (below), so every event in the log lives inside a turn.
+  // Drain before opening the turn, but append only after `turn/start`.
   const queued = handle.inbox.drainQueued()
   const first = queued[0]
   /* v8 ignore next 3 -- invariant guard: runLoop only calls runTurn when hasQueued */
@@ -331,28 +172,17 @@ async function runTurn(
   let errorReported = false
   let terminalStopped = false
 
-  // Close the open step exactly once (idempotent via stepOpen). Post-commit
-  // session/event observers are contained by Session; a pre-commit validator
-  // failure still escapes so the outer recovery path may retry the boundary or
-  // fail loudly without pretending an uncommitted step/end exists.
+  // Close the committed step once; pre-commit validation failure still escapes.
   const closeStep = (): void => {
     if (!stepOpen) return
     session.append('step/end', { turn, step })
     stepOpen = false
   }
 
-  // Record a step/turn failure exactly once: set the error reason (carrying the
-  // failing `step` — the durable failure lives entirely on turn/end.reason, there
-  // is no separate session error event) and emit agent/error (contained — trap: a
-  // throwing agent/error listener must not re-escape and strand the turn).
-  // Disposal and abort set `reason` directly without calling this (they are not
-  // failures).
+  // Record the durable turn failure once and contain the live error notification.
   const failTurn = (err: CodedError): void => {
     if (errorReported) return
     errorReported = true
-    // The turn is still open here. Post-commit observers cannot escape append,
-    // and a pre-commit turn/end veto leaves no closing boundary to overwrite.
-    // Set the reason that the next successful closeTurn will append.
     reason = { kind: 'error', step, ...errorData(err) }
     try {
       events.emit('agent/error', turn, step, err)
@@ -362,9 +192,7 @@ async function runTurn(
     }
   }
 
-  // Close the turn. Post-commit observer failures are contained by Session;
-  // pre-commit validation failures escape to recovery instead of being mistaken
-  // for a committed boundary. Turn boundaries are durable session events only.
+  // Pre-commit validation failure escapes rather than masquerading as a committed boundary.
   const closeTurn = (): void => {
     session.append('turn/end', { turn, reason })
   }
@@ -414,11 +242,7 @@ async function runTurn(
     }
 
     while (true) {
-      // A fully-blocked batch (every prompt vetoed by prompt-submit) opens a
-      // zero-step turn that ends `rejected`: break BEFORE the first step so the
-      // boundary stays balanced (turn/start → turn/end) and the block is a
-      // durable in-turn fact. `anyAllowed` never changes inside the loop, so this
-      // only ever fires on the first iteration.
+      // A fully blocked batch closes its zero-step turn as rejected.
       if (!anyAllowed) {
         reason = { kind: 'rejected', reason: lastBlockReason }
         break
@@ -437,48 +261,20 @@ async function runTurn(
       const abort = new AbortController()
       handle.setAbort(abort)
 
-      // Assemble the system prompt for this step. Done HERE (before step/start)
-      // because the pre-step seam needs it: compaction measures token pressure
-      // against the system prompt (it counts toward the budget). runStep reuses
-      // this same assembly for the request, so the prompt is assembled once per
-      // step. renderPrompt IS the full prompt — the persona is the order-0
-      // section (owned by dsh-system-prompt) and `{{variable}}`
-      // interpolation happens in the render, so there is no separate join.
+      // Assemble once before pre-step so pressure checks and the request share the same prompt.
       const assembly = await ctx.systemPrompt.assemble(assembleContextFor(agent))
       const fullSystemPrompt = renderPrompt(assembly)
 
-      // Interruption landing after assembly: dispose() or cancel() in a
-      // turn-start listener (or a listener whose promise resolved before the
-      // await above) arms either handle.isDisposed() or handle.isCancelled().
-      // The Abort was created first, so any concurrent abort also lands on it.
-      // Drop the about-to-start step WITHOUT running the seam — no step is open
-      // yet, so end the turn accordingly (disposed wins for an unambiguous
-      // reason).
+      // Cancellation or disposal during assembly ends the turn before any step opens.
       if (handle.isCancelled() || handle.isDisposed()) {
         handle.setAbort(undefined)
         reason = handle.isDisposed() ? { kind: 'disposed' } : { kind: 'aborted', reason: handle.cancelReason() }
         break
       }
 
-      // Compose the session prefix ONCE per loop instance, lazily before the
-      // instance's first pre-step: request-only messages placed in front of
-      // the ENTIRE derived history on every request this instance sends. It
-      // MUST precede the pre-step seam so compaction gates on THIS instance's
-      // prefix — reading a previous instance's logged prefix would let a
-      // resumed/forked instance whose contributor grew skip compaction and
-      // ship an over-window first request. The result is deep-cloned
-      // (decoupled from listener-held references), deep-frozen, and cached on
-      // the transmission bookkeeping, so reuse is structural — the prefix
-      // cannot change mid-session and the provider prefix cache holds by
-      // construction (resume = a new instance = a recompose, anchored by its
-      // 'resume' snapshot). The prefix is not session history — the header
-      // event in runStep is its only durable record
-      // (EpochHeader.messagePrefix). The frozen empty seed serves both the
-      // listener chain and the no-listener fallback: a contribution is a
-      // RETURNED extension of `await next()`, never an in-place push. This
-      // runs OUTSIDE the step, before the boundary snapshot: a composing
-      // listener's session append lands before the boundary and joins the
-      // CURRENT request.
+      // Compose the request-only prefix once per loop instance before pressure
+      // checks. It precedes all derived history and is recorded only in the
+      // request header, not as session history.
       if (transmission.sessionPrefix === undefined) {
         const emptyPrefix: Message[] = deepFreeze([])
         const composed = await events.waterfall(
@@ -486,16 +282,7 @@ async function runTurn(
           () => Promise.resolve(emptyPrefix),
         )
 
-        // Interruption landing during prefix composition: mirror the assembly
-        // window above — drop the about-to-start step without running the
-        // seam, and DISCARD the composition instead of caching it. An
-        // abort-aware listener may have returned a degraded fallback under
-        // the firing signal; committing it would ship a prefix no request
-        // ever used (and no header ever logged) on this instance's next real
-        // request. The next turn recomposes under a live signal — the cache
-        // only ever holds a fully composed prefix. The cache-hit path needs
-        // no such check: nothing awaits between the assembly check above and
-        // the pre-step seam.
+        // Never cache an interrupted composition; the next turn recomposes it.
         if (handle.isCancelled() || handle.isDisposed()) {
           handle.setAbort(undefined)
           reason = handle.isDisposed() ? { kind: 'disposed' } : { kind: 'aborted', reason: handle.cancelReason() }
@@ -504,19 +291,7 @@ async function runTurn(
         transmission.sessionPrefix = deepFreeze(structuredClone(composed))
       }
 
-      // Pre-step surface-mutation checkpoint (compaction), fired OUTSIDE the
-      // step: after `turn/start` (and the prior step's close) but before
-      // `step/start`, so a compaction's log-only `compact/*` records and its
-      // replacement node land cleanly outside any step (honest structure that
-      // crash-safety relies on — a dangling `compact/start` sits before the
-      // synthetic `turn/end` repair appends). Serial (awaited, in order, no
-      // veto): each listener completes its surface mutation before the next, so
-      // concurrent listeners cannot interleave their `session.append`s. A
-      // throwing listener escapes to the outer catch, which closes the (not-yet-
-      // open) step as a no-op and ends the turn via failTurn — a broken
-      // pre-step plugin ends the turn, not the loop. The composed session
-      // prefix rides along so token-pressure listeners count everything the
-      // request will actually carry.
+      // Await surface mutations outside the step; pressure checks receive the pending prefix.
       await events.serial('agent/pre-step', turn, step, fullSystemPrompt, transmission.sessionPrefix, abort.signal)
 
       // Interruption landing during the pre-step seam: do not open an empty step.
@@ -526,16 +301,8 @@ async function runTurn(
         break
       }
 
-      // The reconstruction boundary (the reconstructability RFC): the request's
-      // messages are snapshotted HERE, in the same synchronous frame as the
-      // step/start append directly below — so the snapshot is exactly the
-      // derivation over the log prefix strictly before step/start's seq.
-      // Anything appended later by the request-window inject seam or a
-      // concurrent task lands after the boundary and joins the NEXT request.
-      // session/event itself is observe-only: append reentrancy is rejected
-      // until the current callback list drains. An external reconstructor
-      // recovers these exact messages by folding the surface over
-      // events[0..stepStartSeq).
+      // Snapshot the exact log prefix before step/start: the reconstruction
+      // boundary. Appends after this synchronous snapshot join the next request.
       const boundaryMessages = session.deriveMessages()
 
       session.append('step/start', { turn, step })
@@ -582,13 +349,7 @@ async function runTurn(
         break
       }
 
-      // The successful step's finish reason carries forward: a `max-tokens`
-      // step makes the whole turn end `max-tokens` (the ACP RFC's rule "any
-      // max-tokens step surfaces as max-tokens"). `stepFinishReason` returns
-      // `max-tokens` or `undefined`, so a later ordinary step never resets a
-      // max-tokens turn back to completed, and a never-truncated turn keeps the
-      // default `completed`. The disposal/abort/error branches above and the
-      // continuation-window disposal check below override this — they win.
+      // Preserve max-token completion unless a later disposal, abort, or error wins.
       const stepReason = stepFinishReason(stepOutcome.finish)
       if (stepReason) reason = stepReason
 
@@ -610,24 +371,16 @@ async function runTurn(
         break
       }
 
-      // A forced `continue` may carry model-facing context: record it as
-      // next-STEP steering (the steering channel), so the continued turn's next
-      // iteration drains it before its request — the typed twin of the /goal
-      // step/end-steer pattern.
+      // A continuation reason becomes next-step steering.
       if (decision.action === 'continue' && decision.reason) {
         handle.inbox.steer({ content: decision.reason.content, source: decision.reason.source })
       }
       let shouldContinue = decision.action === 'continue'
 
-      // Steering from step/end session-event or continuation listeners (the
-      // /goal pattern) demands the model see it — it overrides a stop decision;
-      // the next iteration's drain records it.
+      // Pending steering overrides an ordinary stop.
       if (!shouldContinue && handle.inbox.hasSteering) shouldContinue = true
 
-      // Terminal policy runs only AFTER the extensible continuation waterfall,
-      // its optional reason, and late steering have all been folded. Unlike the
-      // waterfall, this serial seam is monotonic: the first stop bail wins, and
-      // no later listener or steering override can resurrect the turn.
+      // Terminal policy is monotonic and runs after ordinary continuation folding.
       let terminalStop = false
       try {
         const stop = await events.serial('agent/turn-stop', turn)
@@ -640,19 +393,12 @@ async function runTurn(
       }
       if (terminalStop) {
         terminalStopped = true
-        // A continuation reason or listener may have queued steering before the
-        // terminal checkpoint. Discard only steering (never ordinary queued
-        // prompts) so it cannot become a next step or be re-enqueued as a fresh
-        // turn by runLoop's late-steering fallback.
+        // Terminal stop discards steering but preserves ordinary queued prompts.
         handle.inbox.drainSteering()
         shouldContinue = false
       }
 
-      // A cancel that landed during the continuation window — after the step's
-      // AbortController was cleared (setAbort(undefined)) but before the next
-      // step starts — has no controller to observe it, so the turn-scoped marker
-      // ends the turn here. cancel() also cleared the steering FIFO, so the
-      // override above did not re-arm continuation.
+      // The marker catches cancellation after the step controller was cleared.
       if (handle.isCancelled()) {
         reason = { kind: 'aborted', reason: handle.cancelReason() }
         break
@@ -668,19 +414,11 @@ async function runTurn(
     // Normal / inline-error loop exit: close the turn.
     closeTurn()
   } catch (error: unknown) {
-    // Decide whether this turn opened from the LOG, not a speculative flag. A
-    // pre-commit validator or acceptance failure leaves no turn/start and owes
-    // no turn/end, so it propagates to runLoop's backstop. Once turn/start is
-    // present, this path balances any committed step and records the failure.
+    // Close only a turn whose start committed to the log.
     const turnStartLogged = session.events.some(e => e.type === 'turn/start' && e.data.turn === turn)
     if (!turnStartLogged) throw error
     closeStep()
-    // Choose the close reason. Disposal wins only if no error was already
-    // reported: a turn disposed mid-step sets reason=disposed in the step-error
-    // branch (without reporting an error), so preserve disposed rather than
-    // overwrite it. Otherwise a mid-step throw on a live agent is a real
-    // failure → failTurn. (errorReported is mutated only inside the failTurn
-    // closure, which the analyzer can't follow, hence the inline lint-disable.)
+    // Preserve an established disposal reason; otherwise report the failure.
     if (handle.isDisposed() && !errorReported) { // eslint-disable-line @typescript-eslint/no-unnecessary-condition
       reason = { kind: 'disposed' }
     } else {
@@ -689,19 +427,11 @@ async function runTurn(
     closeTurn()
   }
 
-  // Durability checkpoint: persistence plugins drain write-behind buffers.
-  // A failing persistence plugin is reported but doesn't kill the agent.
-  // Through the store's flush (the carrier owner), never a raw parallel.
+  // Flush through the store-owned durability checkpoint without killing the driver on failure.
   try {
     await ctx.sessions.flush(session)
   } catch (error: unknown) {
-    // The turn is already closed (turn/end appended above) and flush must run
-    // AFTER turn/end to be a checkpoint — so there is no in-turn position left
-    // for a session `error` event. Appending one here would land it after the
-    // last turn/end, where the persistence backend treats it as a crash tail
-    // and drops it on resume (the turn-enclosure RFC: every event is turn-enclosed). Report
-    // the failure via agent/error + the logger only; persistence keeps the
-    // buffered events for the next flush/dispose, so nothing is lost.
+    // The turn is closed, so report the failed flush live rather than append outside a turn.
     const err = toError(error)
     ctx.logger.warn(`agent "${agent.id}": session/flush failed at turn ${turn}: ${err.message}`)
     try {
@@ -722,13 +452,12 @@ function drainSteering(agent: ReactLoopAgent, inbox: Inbox, turn: number): boole
   return messages.length > 0
 }
 
-/** One step: build the request from the boundary snapshot + the step's
- * header → compose the session prefix if this instance has none yet → log
- * the header event the request owes → stream model → record → execute
- * tools. The caller assembles the
- * system prompt, fires the `agent/pre-step` seam, snapshots the derivation,
- * and opens the step BEFORE calling this, so `boundaryMessages` is exactly
- * the surface prefix at step/start and already reflects any compaction. */
+/**
+ * Run one committed step: transform call config, log the request header, build
+ * the request from the cached prefix plus the step-boundary snapshot, stream and
+ * record the response, then execute tools. The caller has already assembled the
+ * prompt, run `agent/pre-step`, snapshotted history, and opened the step.
+ */
 async function runStep(
   ctx: Context,
   events: AgentEventDispatch,
@@ -743,40 +472,23 @@ async function runStep(
 ): Promise<{ hadToolCalls: boolean; finish: FinishReason }> {
   const { session, options } = agent
 
-  // Seed the call config: the first request of THIS loop instance seeds from
-  // current AgentOptions — explicit options always win over the logged
-  // baseline, which is what keeps fork model-overrides and resume-time
-  // reconfiguration correct. Later steps seed from the log's folded header,
-  // which by then is exactly what this instance last logged.
-  // One deep-cloned, frozen seed serves BOTH the listener chain and the
-  // no-listener fallback: structuredClone decouples it from the session's
-  // cached header fold (a raw reference would let a delegating listener
-  // mutate the fold in place and silently skip the delta log), and the freeze
-  // makes in-place shaping unrepresentable — a switch is a RETURNED
-  // replacement, which the header event below records.
+  // Seed the first request from agent options and later requests from the logged header;
+  // detach and freeze so listeners must return an attributable replacement.
   const seedConfig: LlmCallConfig = deepFreeze(structuredClone(transmission.loggedHeader
     // eslint-disable-next-line @typescript-eslint/no-non-null-assertion -- loggedHeader ⟹ a snapshot is in the log
     ? session.requestHeader()!.config
     : { model: options.model ?? '' }))
 
-  // Shape the call config: listeners return a replacement to switch model or
-  // sampling (the seed is frozen — content shaping is not expressible here;
-  // model-visible content flows through the log channels). The header event
-  // below records whatever the request ACTUALLY uses, so a listener's switch
-  // is a logged, reconstructable fact, never silent drift.
+  // Listener replacements are recorded in the request header before dispatch.
   const config = await events.waterfall('agent/request', turn, step, seedConfig, () => Promise.resolve(seedConfig))
   if (!config.model) {
     throw new Error(`agent "${agent.id}" has no model: set AgentOptions.model or supply one via the agent/request waterfall`)
   }
 
-  // The session prefix was composed (once per instance) before this step's
-  // pre-step seam — the caller guarantees it, so the cache is always set here.
   // eslint-disable-next-line @typescript-eslint/no-non-null-assertion -- runTurn composes the prefix before every runStep call
   const sessionPrefix = transmission.sessionPrefix!
 
-  // The request header (the log's request/header* vocabulary): canonical form,
-  // recorded before dispatch so the log always explains the request —
-  // including the session prefix, which no other event carries.
+  // Record the canonical header, including the otherwise-unlogged prefix, before dispatch.
   const header = canonicalHeader({
     config,
     ...system ? { system } : {},
@@ -785,11 +497,7 @@ async function runStep(
   })
   recordRequestHeader(session, transmission, header)
 
-  // Build and freeze: the request is a pure function of (boundary snapshot,
-  // logged header) — llm/stream listeners and adapters read it, mutation
-  // throws. sessionId + frozen is the loop-built marker the dev invariant
-  // keys on. Message order: header.messagePrefix, then the boundary
-  // snapshot — the reconstruction equation the invariant recomputes.
+  // Freeze the logged header plus boundary snapshot; the prefix precedes derived history.
   const request: GenerateOptions = deepFreeze({
     model: header.config.model,
     messages: [...header.messagePrefix ?? [], ...boundaryMessages],
@@ -813,26 +521,16 @@ async function runStep(
     assembler.push(chunk)
   }
 
-  // Adapters report provider/transport failures one of two sanctioned ways
-  // (see the StreamChunk contract in dsh-llm): throw from stream() — already
-  // handled by the caller's try/catch — OR end the stream with a
-  // finish-error/aborted chunk. finishError() maps the latter to the step
-  // error to raise (turn ends error/aborted, not a normal completed message).
+  // Normalize failure finish chunks into the same path as thrown stream errors.
   const stepError = finishError(assembler.finish)
   if (stepError) throw stepError
 
   if (assembler.finish.kind === 'max-tokens') {
     let message: Message = withoutToolCalls(assembler.message())
     message = withoutToolCalls(await events.waterfall('agent/step-result', turn, step, message, () => Promise.resolve(message)))
-    // Fire the assistant/message when there is content OR usage: a max-tokens
-    // step can be cut off with empty content but still carry token accounting,
-    // and assistant/message is the only host for usage (there is no standalone
-    // usage event). An empty-content assistant/message is skipped by
-    // deriveMessages(), so hosting usage on it never injects a spurious assistant
-    // turn into derived history.
+    // Preserve usage even when max-token truncation produced no content.
     if (message.content.length > 0 || assembler.usage) {
-      // A max-tokens finish is itself a streamed `finish` chunk, so chunkSeqs is
-      // never empty here — pass the provenance unconditionally.
+      // The finish chunk guarantees non-empty provenance here.
       session.append(
         'assistant/message',
         { turn, step, content: message.content, ...(assembler.usage ? { usage: assembler.usage } : {}) },
@@ -842,20 +540,11 @@ async function runStep(
     return { hadToolCalls: false, finish: assembler.finish }
   }
 
-  // The step-result waterfall runs BEFORE the session append so the log (the
-  // source of truth for derived history and replay) records the message that
-  // tool dispatch actually uses.
+  // Record the post-waterfall message that tool dispatch uses.
   let message: Message = assembler.message()
   message = await events.waterfall('agent/step-result', turn, step, message, () => Promise.resolve(message))
 
-  // Same content-or-usage guard as the max-tokens branch: a step that finishes
-  // with neither assembled content nor usage (e.g. a bare `stop` finish that
-  // streamed nothing) records no assistant/message — an empty-content message
-  // exists only to host usage, and deriveMessages() skips it either way, so
-  // appending one with no usage would be a pure trace-only row.
-  //
-  // sourceEventSeqs records the assistant/chunk provenance, but is omitted when
-  // no chunks streamed (the surface invariant rejects an empty sourceEventSeqs).
+  // Empty messages exist only to carry usage; omit empty provenance.
   if (message.content.length > 0 || assembler.usage) {
     session.append(
       'assistant/message',
@@ -864,15 +553,9 @@ async function runStep(
     )
   }
 
-  // --- Tool execution (sequential; parallel execution is a TODO) ---
-  // ToolRegistry.execute converts tool failures (including aborts) into
-  // isError results, so abort is re-checked around every call here.
+  // Tool execution stays sequential; recheck abort around each normalized result.
   const toolCalls = message.content.filter(block => block.type === 'tool-call')
-  // Per-step buffer of `additionalContext` attached by tools/post-execute
-  // listeners. Appended as context/message(s) only AFTER every tool/result for
-  // the step, so a multi-call step keeps tool-call/result adjacency
-  // (interleaving context between a call's result and the next call's would
-  // break the pairing the next model request relies on).
+  // Buffer context until all results are appended to preserve call/result adjacency.
   const pendingContext: HookContext[] = []
   for (const call of toolCalls) {
     /* v8 ignore next -- signal.reason always set: cancel()/disposal provide a default */
@@ -884,12 +567,8 @@ async function runStep(
     } catch {
       parsedArguments = call.arguments
     }
-    // TODO(pre-tool-input-rewrite): tools/pre-execute deliberately cannot rewrite
-    // `arguments` — tool/call (the audit record) and assistant/message (the
-    // model-history source) are logged BEFORE execute, and live consumers (ACP,
-    // tool-bash presentation) read the pre-execution args, so an execution-only
-    // rewrite would desync the UI from what ran. Designing that consistently is
-    // its own proposed RFC (docs/rfc/proposed/feature/…-pre-tool-input-rewrite.md).
+    // TODO(pre-tool-input-rewrite): Keep logged history and live presentation aligned;
+    // see docs/rfc/proposed/feature/2026-06-30-pre-tool-input-rewrite.md.
     const result = await ctx.tools.execute({
       callId: call.id,
       name: call.name,
@@ -905,23 +584,18 @@ async function runStep(
       content: result.content,
       isError: result.isError,
       ...result.error ? { error: result.error } : {},
-      // The tool's private presentation payload (e.g. a result-time diff),
-      // persisted so a UI bridge reproduces the card on replay.
+      // Persist tool-owned presentation data for replay.
       ...result.meta !== undefined ? { meta: result.meta } : {},
     }, { surfaceOp: 'append', sourceEventSeqs: [callEvent.seq] })
-    // Buffer (don't append yet) any post-execute additionalContext for this call.
     if (result.additionalContext) pendingContext.push(result.additionalContext)
-    // signal CAN flip during the await above (abort() inside a tool);
-    // the analyzer can't see through the await boundary.
+    // The signal may flip while the tool is awaited.
     /* v8 ignore start -- signal.reason default unreachable: cancel()/disposal always set it */
     // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
     if (signal.aborted) throw new Error(String(signal.reason ?? 'aborted'))
     /* v8 ignore stop */
   }
 
-  // Append buffered post-execute context AFTER every tool/result, preserving
-  // tool-call/result adjacency across the whole batch. inject() appends into the
-  // open turn (a context/message at its chronological position).
+  // Append buffered context after the complete result batch.
   for (const context of pendingContext) {
     agent.inject(context.content, { source: context.source })
   }
@@ -944,13 +618,8 @@ export function lastTurnNumber(session: Session): number {
 }
 
 /**
- * Whether a turn is currently open in the session log (a `turn/start` with no
- * matching later `turn/end`). Decided from the LOG, not agent status: status
- * can be `running` while no turn is open (an `agent/status` listener firing
- * before `turn/start`, or the post-`turn/end` flush window before status
- * returns to idle), so status is not a reliable open-turn signal. Used by
- * `inject()` to choose between appending into an open turn vs. wrapping the
- * injection in its own one-shot turn (the turn-enclosure RFC).
+ * Whether the session log has an unmatched `turn/start`. Agent status is not
+ * sufficient during pre-start and post-end windows.
  * @param session - the session whose log is inspected.
  * @returns true when the log's last turn boundary is a `turn/start` with no matching `turn/end` yet.
  */

packages/core/agent-loop/src/request-log.ts

@@ -1,12 +1,7 @@
 /**
- * Per-loop-instance transmission bookkeeping for the reconstructability
- * contract: which header event to append before a request so the session log
- * always explains the request (the reconstructability RFC). The loop is
- * otherwise transmission-stateless — the comparison baseline is the log's own
- * folded header (`Session.requestHeader()`), so resume and fork need no
- * special path: a fresh loop instance simply logs a `'resume'` snapshot on
- * its first request and deltas from there.
- *
+ * Per-loop-instance request-header bookkeeping for reconstructability. The
+ * comparison baseline is the header folded from the session log, so a fresh
+ * loop instance needs no special resume or fork state.
  * @module dsh-agent-loop/request-log
  */
 
@@ -37,22 +32,10 @@ export function createTransmissionLog(): TransmissionLog {
 }
 
 /**
- * Append whatever header event this request owes the log, so folding the log
- * reproduces the header the request was built under. Exactly one of four
- * things happens:
- *
- * 1. This loop instance has not logged a header yet → a full `request/header`
- *    snapshot anchors the fold: reason `'initial'` when the log has no header
- *    events at all (a new conversation), `'resume'` when it does (process
- *    restart, fork seed — the boundary itself is a recorded fact, so the
- *    snapshot is appended even when nothing changed).
- * 2. The header equals the folded baseline → nothing; the log already
- *    explains this request.
- * 3. It differs and the delta round-trips (`applyHeaderDelta` on the baseline
- *    reproduces the header exactly) → a `request/header-delta`.
- * 4. It differs and the delta encoding cannot express the change (a pure tool
- *    reordering) → a full snapshot with reason `'fallback'`; deltas are an
- *    encoding optimization, never a correctness dependency.
+ * Append whatever header event makes the log reproduce this request's header.
+ * The first request from an instance always records a full `initial` or `resume`
+ * snapshot. Later requests record nothing when unchanged, a round-tripping
+ * delta when expressible, or a full `fallback` snapshot otherwise.
  *
  * @param session - the session whose log explains the request.
  * @param state - this loop instance's bookkeeping (mutated on first log).

packages/core/agent-loop/tests/agent.spec.ts

@@ -167,10 +167,8 @@ describe('ReactLoopAgent', () => {
     let flushes = 0
     ctx.on('session/flush', () => { flushes += 1 })
 
-    // Non-serializable injected content makes Session.append throw AFTER
-    // turn/start was recorded. The turn/end must still be appended (finally),
-    // AND the durability checkpoint must still fire — the balanced turn is in
-    // memory and a crash before the next turn/dispose would otherwise lose it.
+    // Invalid injected content throws after turn/start. `finally` must still append turn/end and
+    // flush the balanced in-memory turn so a crash cannot lose it before the next checkpoint.
     expect(() => {
       agent.inject([{ type: 'text', text: 'x', bad: 1n } as never], { source: { kind: 'plugin', plugin: 'p' } })
     }).toThrow(/non-JSON-serializable/)
@@ -252,26 +250,20 @@ describe('ReactLoopAgent', () => {
   })
 
   it('disposer is idempotent (double-stop)', async () => {
-    // Create a bare ReactLoopAgent and start it through the package-internal
-    // test seam. Then call its disposer twice — the second call hits the
-    // early-return branch.
+    // The internal start seam exposes one idle driver's disposer for repeated invocation.
     const ctx = new Context()
     await ctx.plugin(SessionStore)
     const session = ctx.sessions.create(SessionId('test'))
     const prepared = prepareReactLoopAgent(ctx, AgentId('bare'), { model: 'mock' }, session)
     const { agent } = prepared
 
-    // Start the loop to get the disposer; the agent waits for messages
-    // (idle, never-resolving cancel), so it will stay idle.
     prepared.markPublished()
     const dispose = prepared.startDriver()
 
-    // First dispose
     const firstDisposal = dispose()
     expect(agent.status).toBe('disposed')
     await firstDisposal
 
-    // Second dispose — idempotent, no throw
     await expect(dispose()).resolves.toBeUndefined()
     expect(agent.status).toBe('disposed')
   })
@@ -366,10 +358,8 @@ describe('ReactLoopAgent', () => {
   })
 
   it('whenIdle() subscribed while running resolves via done when the agent is then disposed', async () => {
-    // Covers the waiter's disposed arm: whenIdle() queues an internal waiter
-    // while running (not the fast path), then the disposer settles it and chains
-    // `done` (loop exit), not an eager resolve. A bare ReactLoopAgent + direct
-    // internal driver disposer keeps the emit synchronous.
+    // Queue the internal waiter while running, then dispose the bare driver. Its disposed branch
+    // must chain the loop's `done` promise rather than resolve before exit.
     const ctx = new Context()
     await ctx.plugin(LlmService)
     await ctx.plugin(SessionStore)
@@ -395,11 +385,8 @@ describe('ReactLoopAgent', () => {
   })
 
   it('whenIdle() subscribed while running survives a FIBER dispose (no hung promise)', async () => {
-    // The waiter is internal agent state, NOT an effect-scoped ctx.on listener:
-    // disposing the OWNING fiber runs the agent's listener disposers, which would
-    // have dropped a ctx.on-based waiter before the 'disposed' transition and
-    // hung the promise. With internal waiters, the fiber disposer still settles
-    // it. Regression for the round-3 whenIdle finding.
+    // The waiter is agent-owned state, not an effect-scoped listener that owner disposal would
+    // remove before the disposed transition. Fiber teardown must still settle it.
     const adapter = new MockAdapter(['hang'])
     const ctx = await harness(adapter)
     let agent!: ReactLoopAgent
@@ -417,10 +404,8 @@ describe('ReactLoopAgent', () => {
   })
 
   it('whenIdle() on a disposed agent awaits the loop exit (done), not just the status flip', async () => {
-    // The disposer emits agent/status('disposed') BEFORE the driver loop
-    // unwinds, so whenIdle() must chain `done` (true quiescence) on the
-    // disposed path. Dispose a running agent, then assert whenIdle() resolves
-    // only after `done` — i.e. the loop has actually exited.
+    // Disposed status is emitted before the driver unwinds. `whenIdle()` must chain `done` so it
+    // resolves only after true loop exit.
     const adapter = new MockAdapter(['hang'])
     const ctx = await harness(adapter)
     let agent!: ReactLoopAgent

packages/core/agent-loop/tests/cancel.spec.ts

@@ -1,12 +1,9 @@
 /**
- * Tests for the queue-aware `Agent.cancel()` primitive. `cancel()` is the
- * broad verb — it clears queued + steering work, aborts an in-flight step, and
- * drops a turn about to start — whereas a bare step abort (the loop's private
- * `AbortController`) kills only the current step and leaves the queue intact.
- * These tests exercise every window where a cancel can land (idle, pre-step,
- * mid-step, continuation) and the marker's arm/reset rules that keep a cancel
- * from leaking to a later prompt or hanging `whenIdle()`.
- *
+ * Tests for the queue-aware `Agent.cancel()` primitive. `cancel()` is the broad verb — it
+ * clears queued + steering work, aborts an in-flight step, and drops a turn about to start —
+ * whereas a bare step abort (the loop's private `AbortController`) kills only the current step
+ * and leaves the queue intact. The suite covers every landing window plus marker
+ * reset and `whenIdle()` quiescence.
  * @module dsh-agent-loop/tests/cancel
  */
 
@@ -95,10 +92,8 @@ describe('Agent.cancel()', () => {
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
-    // Queue work, then register a whenIdle() waiter while in the pre-step window
-    // (status idle, hasQueued true) — it does NOT take the fast path. Then cancel.
-    // The skip path must settle this waiter directly (no running→idle transition
-    // ever fires), or it would hang forever.
+    // This waiter cannot rely on a running→idle transition because cancellation
+    // drops the turn before it runs; the skip path must settle it directly.
     send(agent, 'q')
     const idle = agent.whenIdle()
     agent.cancel('pre-step')
@@ -234,12 +229,8 @@ describe('Agent.cancel()', () => {
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
-    // The first composition is interrupted mid-waterfall and — like an
-    // abort-aware listener bailing on a firing signal — contributes nothing.
-    // Caching that degraded result would silently strip the prefix from every
-    // later request of this instance; the loop must discard it and recompose
-    // on the next send, and the SECOND composition's value must be what the
-    // wire and the header log carry.
+    // The interrupted first composition must not cache its degraded empty value;
+    // the next prompt recomposes and logs/sends the fresh prefix.
     const opener: Message = { role: 'user', content: [{ type: 'text', text: 'fresh opener' }] }
     let compositions = 0
     ctx.on('agent/session-prefix', async (_agent, _prefix, _signal, next): Promise<Message[]> => {
@@ -268,10 +259,8 @@ describe('Agent.cancel()', () => {
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
-    // A turn/start listener fires right after turn/start is appended, BEFORE any
-    // AbortController is installed for the step. Cancelling there must still drop
-    // the step (the turn-scoped marker, not the step AbortController, is what
-    // catches this) — no model step runs.
+    // A turn/start listener fires before a step controller exists, so the
+    // turn-scoped marker—not step abort—must drop the pending step.
     let streamed = false
     ctx.on('session/event', (_s, event) => { if (event.type === 'assistant/chunk') streamed = true })
     const dispose = ctx.on('session/event', (session, event) => {
@@ -400,10 +389,8 @@ describe('Agent.cancel()', () => {
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
 
-    // setStatus('running') emits agent/status SYNCHRONOUSLY, so a running
-    // listener can cancel in the gap between the loop's pre-step check and
-    // runTurn. The second check (after the running flip) must drop the turn —
-    // runTurn would otherwise throw on the now-empty queue.
+    // `agent/status` is synchronous, so cancellation can land after the first
+    // pre-step check; the second check must drop the now-empty turn.
     let streamed = false
     ctx.on('session/event', (_s, event) => { if (event.type === 'assistant/chunk') streamed = true })
     const dispose = ctx.on('agent/status', (subject, status) => {
@@ -421,11 +408,7 @@ describe('Agent.cancel()', () => {
   })
 
   it('window 2: whenIdle() does NOT resolve early when a running listener cancels then queues replacement work', async () => {
-    // The window-1 early-resolve race has a window-2 twin: a synchronous
-    // agent/status('running') listener cancels the about-to-run turn AND queues a
-    // replacement. window 2 must NOT settle waiters (via setStatus('idle')) while
-    // the replacement is still queued-and-unrun — it must fall through and run it,
-    // so whenIdle() resolves on the replacement turn's running→idle, not before.
+    // Cancellation must not settle idle while replacement work remains queued.
     const adapter = new MockAdapter([textResponse('A reply'), textResponse('B reply')])
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
@@ -451,11 +434,8 @@ describe('Agent.cancel()', () => {
   })
 
   it('whenIdle() does NOT resolve early when a new prompt is queued during a pre-step cancel', async () => {
-    // The subtle race: a whenIdle() waiter is registered for prompt A; cancel()
-    // clears A; prompt B is queued BEFORE the loop resumes from the idle wait.
-    // The window-1 cancel branch must NOT settle the waiter while B is still
-    // queued-and-unrun — whenIdle() must wait for B's turn to actually run and
-    // settle (the quiescence contract), not resolve before B's first event.
+    // The subtle race: a whenIdle() waiter is registered for prompt A; cancel() clears A;
+    // prompt B is queued before the loop resumes from the idle wait.
     const adapter = new MockAdapter([textResponse('A reply'), textResponse('B reply')])
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
@@ -465,9 +445,8 @@ describe('Agent.cancel()', () => {
     agent.cancel('drop A')     // arms marker, clears A
     send(agent, 'B')           // B races in before the loop resumes
 
-    // whenIdle() must resolve only AFTER B's turn fully ran — by which point B's
-    // user message and a turn/end are in the log. (Before the fix it resolved
-    // immediately, with zero events, then B ran afterward.)
+    // whenIdle() must resolve only after B's turn fully ran — by which point B's user message
+    // and a turn/end are in the log.
     await idle
     expect(userTexts(agent)).toContain('B')
     expect(agent.session.events.some(e => e.type === 'turn/end')).toBe(true)

packages/core/agent-loop/tests/config-session-id.spec.ts

@@ -101,9 +101,8 @@ describe('config-driven session id', () => {
     await waitForIdle(ctx1, a1)
     await ctx1.fiber.dispose()
 
-    // Run 2: a CONFIG agent with resumeSessionId continues that session. The
-    // resume is deferred until sessionPersistence loads (ctx.inject), so wait
-    // for the agent to appear, then assert it is on the resumed id with history.
+    // Resume waits for the injected persistence service, so poll until the
+    // config-created agent appears with its stored history.
     const ctx2 = new Context()
     await ctx2.plugin(LlmService)
     await ctx2.plugin(SessionStore)

packages/core/agent-loop/tests/contract-regressions.spec.ts

@@ -39,7 +39,7 @@ function send(agent: ReactLoopAgent, text: string) {
   agent.send([{ type: 'text', text }])
 }
 
-describe('HIGH: session log records what agent/step-result actually produced', () => {
+describe('session log records what agent/step-result actually produced', () => {
   it('a step-result rewrite is what the log, derived history, and tool dispatch all see', async () => {
     const adapter = new MockAdapter([textResponse('original'), textResponse('done')])
     const ctx = await harness(adapter)
@@ -89,7 +89,7 @@ describe('HIGH: session log records what agent/step-result actually produced', (
   })
 })
 
-describe('HIGH: abort during tool execution ends the turn', () => {
+describe('abort during tool execution ends the turn', () => {
   it('aborting the in-flight step inside a tool prevents both remaining tools and the next model step', async () => {
     const adapter = new MockAdapter([
       // model asks for two tool calls in one step
@@ -141,7 +141,7 @@ describe('HIGH: abort during tool execution ends the turn', () => {
   })
 })
 
-describe('HIGH: steering from late extension points is never stranded', () => {
+describe('steering from late extension points is never stranded', () => {
   it('steer() from an agent/turn-continuation listener overrides a stop decision', async () => {
     const adapter = new MockAdapter([
       textResponse('no tools, would stop here'),
@@ -168,21 +168,7 @@ describe('HIGH: steering from late extension points is never stranded', () => {
   })
 
   it('steer() from a step/end session-event listener forces a SAME-TURN next step (/goal pattern)', async () => {
-    // The /goal pattern steers from a step boundary so the model addresses a
-    // standing goal before stopping. Step boundaries have no agent/* mirror, so
-    // the surviving hook point is the durable step/end session event. With a
-    // no-tools first step the default continuation is stop; the steering queued
-    // here must force the `!shouldContinue && hasSteering` override so the SAME
-    // turn runs another step.
-    //
-    // The override is what this test guards, so it asserts the same-turn shape —
-    // NOT merely that the content reaches requests[1]. Without the override the
-    // turn would stop, and leftover steering is re-enqueued as a next-turn queued
-    // message, which ALSO lands in requests[1] (just one turn later). So a
-    // content-only assertion passes with the override disabled and guards
-    // nothing. The discriminator is the turn/step shape: override ⇒ ONE turn with
-    // TWO steps and the steering recorded as a `steering/message` BEFORE step 2;
-    // re-enqueue fallback ⇒ TWO turns.
+    // Assert the same-turn shape; content alone cannot distinguish re-enqueue.
     const adapter = new MockAdapter([
       textResponse('no tools, would stop'),
       textResponse('after goal reminder'),
@@ -200,12 +186,10 @@ describe('HIGH: steering from late extension points is never stranded', () => {
     send(agent, 'go')
     await waitForIdle(ctx, agent)
 
-    // Same-turn continuation: the steering forced step 2 within turn 1.
     const events = [...agent.session.events]
     expect(events.filter(e => e.type === 'turn/start')).toHaveLength(1)
     expect(events.filter(e => e.type === 'step/start')).toHaveLength(2)
-    // The steered content is recorded as steering (same turn), BEFORE step 2 —
-    // not as a fresh turn's user/message. This is the mechanism the override uses.
+    // Same-turn steering precedes the second step.
     const steeringIdx = events.findIndex(e => e.type === 'steering/message')
     const step2Idx = events.map(e => e.type).lastIndexOf('step/start')
     expect(steeringIdx).toBeGreaterThanOrEqual(0)
@@ -263,7 +247,7 @@ describe('HIGH: steering from late extension points is never stranded', () => {
   })
 })
 
-describe('HIGH: plugin exceptions are contained', () => {
+describe('plugin exceptions are contained', () => {
   it('a throwing agent/turn-continuation listener ends the turn with an error, loop survives', async () => {
     const adapter = new MockAdapter([textResponse('one'), textResponse('two')])
     const ctx = await harness(adapter)
@@ -318,7 +302,7 @@ describe('HIGH: plugin exceptions are contained', () => {
   })
 })
 
-describe('MEDIUM: disposed status is part of the agent/status contract', () => {
+describe('disposed status is part of the agent/status contract', () => {
   it('disposing the fiber emits agent/status(disposed) and ends the turn with reason disposed', async () => {
     const adapter = new MockAdapter(['hang'])
     const ctx = await harness(adapter)
@@ -365,7 +349,7 @@ describe('MEDIUM: disposed status is part of the agent/status contract', () => {
   })
 })
 
-describe('MEDIUM: misc registry and config fixes', () => {
+describe('adapter registration, routing, and accepted-input ownership', () => {
   it('duplicate adapter registration is rejected', async () => {
     const ctx = new Context()
     await ctx.plugin(LlmService)
@@ -524,7 +508,7 @@ describe('MEDIUM: misc registry and config fixes', () => {
   })
 })
 
-describe('MEDIUM: turn numbering continues across seeded (forked) sessions', () => {
+describe('turn numbering continues across seeded sessions', () => {
   it('a forked agent continues turn numbers after the seed log', async () => {
     const first = new MockAdapter([textResponse('turn one')])
     const ctx = await harness(first)
@@ -562,7 +546,7 @@ describe('MEDIUM: turn numbering continues across seeded (forked) sessions', ()
   })
 })
 
-describe('LOW: discriminated SessionEvent narrows without casts', () => {
+describe('discriminated SessionEvent narrows without casts', () => {
   it('narrows event.data from event.type', () => {
     const session = new Session(SessionId('s'))
     const appended: SessionEvent = session.append('tool/call', {
@@ -580,12 +564,9 @@ describe('LOW: discriminated SessionEvent narrows without casts', () => {
   })
 })
 
-describe('HIGH: a finish-error stream chunk ends the turn as error, not completed', () => {
+describe('a finish-error stream chunk ends the turn as error, not completed', () => {
   it('translates finish {kind:error} into a turn error with a logged error event', async () => {
-    // The second sanctioned adapter error path (besides throwing): an
-    // adapter that cannot throw mid-stream ends the stream with a
-    // finish-error chunk (e.g. the pi-ai adapter mapping a provider 401).
-    // The loop must NOT log a normal assistant/message + completed turn.
+    // A finish-error chunk must not produce a completed assistant turn.
     const errorStream: StreamChunk[] = [
       { type: 'finish', reason: { kind: 'error', message: 'provider 401', code: 'AUTH' } },
     ]
@@ -606,7 +587,7 @@ describe('HIGH: a finish-error stream chunk ends the turn as error, not complete
     // a standalone error event.
     const turnEnd = events.find(event => event.type === 'turn/end')
     expect(turnEnd?.type === 'turn/end' && turnEnd.data.reason).toEqual({ kind: 'error', step: 1, message: 'provider 401', code: 'AUTH' })
-    // Crucially: no assistant/message was logged for the failed step.
+    // A failed step must not synthesize an assistant message.
     expect(events.some(event => event.type === 'assistant/message')).toBe(false)
   })
 
@@ -652,10 +633,7 @@ describe('step boundary publication order', () => {
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a-step-order'), { model: 'mock' })
 
-    // Session.append pushes the event BEFORE notifying session/event listeners,
-    // so a step/start listener always finds the matching event already in the
-    // log. (Step boundaries have no agent/* mirror — the session log is the live
-    // feed.)
+    // Append commits before observers run.
     const observed: { turn: number; step: number; lastEventType: string | undefined; sawStepStart: boolean }[] = []
     ctx.on('session/event', (subject, event) => {
       if (subject !== agent.session || event.type !== 'step/start') return
@@ -678,10 +656,7 @@ describe('step boundary publication order', () => {
 })
 
 describe('turn and step boundary recovery', () => {
-  // Harness with the invariants plugin loaded as an oracle: it throws on
-  // append if the log goes unbalanced (turn/end while a step is open,
-  // turn/start while a turn is open, etc.), so a regression surfaces as an
-  // InvariantError on the NEXT turn's append rather than a silent imbalance.
+  // The invariants plugin makes an unbalanced log fail the test.
   async function balancedHarness(adapter: MockAdapter) {
     const ctx = new Context()
     await ctx.plugin(LlmService)
@@ -833,9 +808,7 @@ describe('turn and step boundary recovery', () => {
   })
 
   it('a throwing agent/error listener during a step-error path still balances the turn, loop survives', async () => {
-    // First turn: model stream ends with a finish-error → step error path →
-    // failTurn emits agent/error, whose listener throws. The turn must still
-    // close balanced. Second turn proves the loop survived.
+    // Listener failure cannot interrupt error finalization or the next turn.
     const errorStream: StreamChunk[] = [{ type: 'finish', reason: { kind: 'error', message: 'provider 500' } }]
     const adapter = new MockAdapter([errorStream, textResponse('turn 2 ok')])
     const ctx = await balancedHarness(adapter)
@@ -894,9 +867,7 @@ describe('turn and step boundary recovery', () => {
   })
 
   it('preserves reason disposed when a pre-step listener disposes then throws (outer-catch disposed branch)', async () => {
-    // A pre-step listener requests disposal and then throws before the ordinary
-    // post-listener disposal check. The outer catch sees disposal already won
-    // and must preserve reason=disposed rather than rewrite it as a plugin error.
+    // Disposal remains authoritative when the listener also throws.
     const adapter = new MockAdapter([textResponse('never reached')])
     const ctx = await balancedHarness(adapter)
     let agent!: ReactLoopAgent
@@ -908,9 +879,6 @@ describe('turn and step boundary recovery', () => {
     ctx.on('agent/pre-step', () => {
       if (threw) return
       threw = true
-      // Request disposal, then throw in the same synchronous tick: status flips
-      // to 'disposed' (the disposer aborts the step controller) and the throw
-      // drives control into the outer catch with isDisposed() already true.
       void fiber.dispose()
       throw new Error('boom pre-step during disposal')
     })
@@ -1001,10 +969,7 @@ describe('turn and step boundary recovery', () => {
   })
 
   it('a throwing step/end observer cannot interrupt error finalization', async () => {
-    // A finish-error stream opens a step then fails it, driving finalization
-    // through closeStep() with the step open. Session contains the observer
-    // failure after committing step/end, so closeTurn still records the model
-    // failure and balances the turn.
+    // Observer failure after step/end commit cannot interrupt turn finalization.
     const errorStream: StreamChunk[] = [{ type: 'finish', reason: { kind: 'error', message: 'provider 500' } }]
     const adapter = new MockAdapter([errorStream, textResponse('turn 2 ok')])
     const ctx = await harness(adapter)
@@ -1110,11 +1075,7 @@ describe('tool result call identity', () => {
 
 describe('surface: assistant/message omits sourceEventSeqs when no chunks streamed', () => {
   it('a step-result listener injecting content over an empty stream appends with surfaceOp but no sourceEventSeqs', async () => {
-    // An empty stream yields zero assistant/chunk events (finish defaults to
-    // `stop`), so chunkSeqs is empty. A step-result listener injects content, so
-    // the content-or-usage guard fires and an assistant/message is appended. Its
-    // sourceEventSeqs MUST be omitted (not `[]`) — the surface invariant rejects
-    // an empty sourceEventSeqs, and the dev invariants plugin would throw on it.
+    // Injected result content with no chunks must omit empty sourceEventSeqs.
     const adapter = new MockAdapter([[]])
     const ctx = await harness(adapter)
     await ctx.plugin(Invariants)
@@ -1141,12 +1102,8 @@ describe('surface: assistant/message omits sourceEventSeqs when no chunks stream
 
 describe('disposal and cancellation during pre-step assembly', () => {
   it('disposal during system-prompt assembly drops the about-to-start step as disposed', { timeout: 30000 }, async () => {
-    // Block `system-prompt/assemble` on a promise. Start disposal (which
-    // calls stop() synchronously, setting status=disposed), then release the
-    // block. The loop must check isDisposed() after assembly and end the turn
-    // `disposed` — no LLM call. Don't await fiber.dispose() before releasing
-    // the blocker: the dispose chain awaits agent.done, which hangs until the
-    // loop unblocks.
+    // Start disposal, then release assembly. Do not await disposal first: it
+    // waits for the blocked driver to exit.
     const adapter = new MockAdapter(['hang'])
     let releaseAssemble!: () => void
     const blocked = new Promise<void>(r => void (releaseAssemble = r))
@@ -1161,7 +1118,7 @@ describe('disposal and cancellation during pre-step assembly', () => {
     await ctx.plugin(Invariants)
     ctx.llm.registerAdapter(['mock'], adapter)
 
-    // Blocking listener on the parent context (survives fiber disposal).
+    // Parent-owned listener survives agent-fiber disposal.
     const unlisten = ctx.on('system-prompt/assemble', async function (_assembly, _context, next) {
       await blocked
       return next()
@@ -1179,28 +1136,22 @@ describe('disposal and cancellation during pre-step assembly', () => {
     // Give the loop time to enter the step and reach assemble().
     await new Promise(r => setTimeout(r, 50))
 
-    // Start disposal — stop() sets status=disposed synchronously, then the
-    // disposer's await agent.done hangs because the loop is blocked in the
-    // waterfall. Do NOT await yet; release the blocker first.
+    // Release assembly before awaiting disposal because disposal joins the blocked driver.
     const disposalDone = fiber.dispose()
 
-    // Now release the blocked waterfall — the loop unblocks, checks
-    // isDisposed(), and exits, which resolves agent.done and disposalDone.
     releaseAssemble()
     await disposalDone
     await agent.done
     unlisten()
 
+    // Turn boundaries are durable rows; there is no `agent/*` mirror to assert.
     const e = [...agent.session.events]
     expect(e.filter(x => x.type === 'turn/start')).toHaveLength(1)
     expect(e.filter(x => x.type === 'turn/end')).toHaveLength(1)
     const turnEnd = e.findLast(x => x.type === 'turn/end')
     expect(turnEnd?.type === 'turn/end' && turnEnd.data.reason).toEqual({ kind: 'disposed' })
-    // No step was opened, no LLM call was made.
     expect(e.some(x => x.type === 'step/start')).toBe(false)
     expect(e.some(x => x.type === 'assistant/chunk')).toBe(false)
-    // The durable turn/end record is the authoritative turn-boundary signal
-    // (turn boundaries have no agent/* mirror), so this asserts on the log.
   })
 
   it('cancel during system-prompt assembly drops the about-to-start step as aborted', { timeout: 30000 }, async () => {
@@ -1257,9 +1208,8 @@ describe('disposal and cancellation during pre-step assembly', () => {
   })
 
   it('disposal during agent/pre-step seam ends the turn disposed', { timeout: 15000 }, async () => {
-    // Block the `agent/pre-step` serial seam on a promise we control, then
-    // dispose the agent's fiber. When the block releases, the loop must see
-    // isDisposed() at the post-seam check and end the turn disposed.
+    // Start disposal, then release pre-step; awaiting disposal first would
+    // deadlock on the blocked driver.
     const adapter = new MockAdapter(['hang'])
     let releasePreStep!: () => void
     const blocker = new Promise<void>(r => void (releasePreStep = r))
@@ -1310,8 +1260,7 @@ describe('disposal and cancellation during pre-step assembly', () => {
   })
 
   it('cancel during agent/pre-step seam ends the turn aborted', { timeout: 15000 }, async () => {
-    // Block `agent/pre-step`, then cancel() the agent. When the block releases,
-    // the post-seam check catches cancellation and ends the turn aborted.
+    // Release pre-step after cancellation to exercise the post-seam check.
     const adapter = new MockAdapter(['hang'])
     let releasePreStep!: () => void
     const blocker = new Promise<void>(r => void (releasePreStep = r))

packages/core/agent-loop/tests/coverage-edges.spec.ts

@@ -225,9 +225,7 @@ describe('disposed vs aborted branching', () => {
     await fiber.dispose() // dispose during hang
     await agent.done
 
-    // The review-fixes test for 'HIGH: disposed status' already covers
-    // this assertion path. The reason is 'disposed' because isDisposed() is
-    // checked before the abort signal check in the error path.
+    // Disposal wins abort classification because the error path checks it first.
     expect(reasons).toContainEqual({ kind: 'disposed' })
   })
 })

packages/core/agent-loop/tests/inbox.spec.ts

@@ -64,17 +64,12 @@ describe('Inbox', () => {
     void inbox.waitForQueued(new Promise(() => {})) // first call, never resolved
     void inbox.waitForQueued(p1) // second call overwrites wakeup
 
-    // Cancel p1 (the latest waiter's cancel) — the wakeup was overwritten
-    // to p1's resolve, so canceling p1 triggers the finally block which
-    // clears the wakeup if it matches.
+    // Cancelling the latest waiter clears the shared callback; enqueue must neither
+    // wake the stale waiter nor fail on the cleared callback.
     r1()
     await p1
 
-    // Now enqueue: the first waiter's wakeup (which was overwritten) won't
-    // fire, and the second waiter's wakeup was cleared by cancel.
-    // The enqueue calls wakeup?.() but wakeup was cleared — no crash, no hang.
     inbox.enqueue({ content: [{ type: 'text', text: 'hey' }], source: { kind: 'user' } })
-    // The overwrite path + finally cleanup are exercised
   })
 
   it('clears wakeup in finally handler when enqueue resolves', async () => {
@@ -88,23 +83,17 @@ describe('Inbox', () => {
   })
 
   it('finally handler does not clear wakeup when a different waiter overwrote it', async () => {
-    // First waiter's cancel resolves AFTER a second waiter overwrote wakeup.
-    // First waiter's finally sees wakeup !== its resolve → does not clear.
+    // A stale waiter's finally must not clear the replacement waiter.
     const inbox = new Inbox()
     const { promise: c1, resolve: r1 } = resolverPair()
 
     void inbox.waitForQueued(c1) // wakeup = resolve1, c1.then(resolve1)
     void inbox.waitForQueued(new Promise(() => {})) // wakeup = resolve2, cancel never resolves
 
-    // Resolve c1 (the first cancel). c1.then(resolve1) fires → resolve1() called
-    // → waiter1's promise resolves → finally: wakeup === resolve1? NO (it's resolve2)
-    // → wakeup is NOT cleared.
     r1()
     await c1
 
-    // Now enqueue: wakeup() calls resolve2 → waiter2 resolves
-    // But waiter2's cancel never resolves — that's fine, enqueue resolves it.
+    // The replacement remains registered and is resolved by enqueue.
     inbox.enqueue({ content: [{ type: 'text', text: 'hey' }], source: { kind: 'user' } })
-    // No need to await anything further — enqueue is synchronous wakeup
   })
 })

packages/core/agent-loop/tests/interception.spec.ts

@@ -117,14 +117,8 @@ describe('agent/prompt-submit', () => {
   })
 
   it('a prompt-submit rewrite + additionalContext is VISIBLE to the agent/pre-step seam (merged ordering)', async () => {
-    // The merge of the interception seams with master's compaction seam pins one
-    // ordering: `agent/prompt-submit` runs (rewriting the prompt and injecting
-    // context) BEFORE the step loop, and `agent/pre-step` fires INSIDE the step
-    // before the single deriveMessages(). So a compaction listener on
-    // `agent/pre-step` must observe the surface AFTER the prompt rewrite/inject —
-    // otherwise it would measure/compact stale history. This cross-test proves
-    // the two seams compose in the right order (each is covered in isolation
-    // elsewhere; this asserts they see each other's effects on the same turn).
+    // Prompt rewrites and injected context land before `agent/pre-step`, so a
+    // compaction listener measures the current surface before the single derive.
     const adapter = new MockAdapter([textResponse('ok')])
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
@@ -189,9 +183,8 @@ describe('agent/prompt-submit', () => {
   })
 
   it('a mixed batch records a prompt/blocked for the vetoed prompt while the allowed one runs', async () => {
-    // Two prompts queued into ONE turn: block "secret", allow "safe". The turn is
-    // NOT rejected (a prompt was allowed), so without a durable prompt/blocked the
-    // vetoed prompt and its reason would vanish from the log entirely.
+    // Blocking one prompt in a mixed batch must persist its reason even though
+    // the allowed prompt keeps the turn from ending rejected.
     const adapter = new MockAdapter([textResponse('ran once')])
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
@@ -515,14 +508,13 @@ describe('agent/turn-continuation (ContinuationDecision)', () => {
     await waitForIdle(ctx, agent)
 
     const log = events(agent)
-    // same turn, two steps
+    // The continuation stays in the turn, is logged with provenance before step 2,
+    // and reaches that step's request.
     expect(log.filter(e => e.type === 'turn/start')).toHaveLength(1)
     expect(log.filter(e => e.type === 'step/start')).toHaveLength(2)
-    // the reason was recorded as steering BEFORE step 2, with its plugin source
     const steering = log.find(e => e.type === 'steering/message')
     expect(steering?.type === 'steering/message' && steering.data.content).toEqual([{ type: 'text', text: 'keep going on the goal' }])
     expect(steering?.type === 'steering/message' && steering.data.source).toEqual({ kind: 'plugin', plugin: 'goal' })
-    // and reached the next request
     expect(JSON.stringify(adapter.requests[1]!.messages)).toContain('keep going on the goal')
   })
 
@@ -618,11 +610,9 @@ describe('tools/pre-execute gate (native-plugin permission pattern, end-to-end t
 })
 
 describe('worked example: a native hook plugin is just a cordis plugin on the seams', () => {
-  // The whole point of the interception taxonomy: a "native hook" needs no
-  // dsh-hook-protocol, no external command, no hook/* log — it is an ordinary
-  // cordis plugin subscribing to the canonical events and returning typed
-  // decisions. This proves all four seams compose end-to-end through the REAL
-  // loop, with NO hook/* SessionEvents involved (those belong to the bridge lib).
+  // The whole point of the interception taxonomy: a "native hook" needs no dsh-hook-protocol,
+  // no external command, no hook/* log — it is an ordinary cordis plugin subscribing to the
+  // canonical events and returning typed decisions.
   const NativeGuard = {
     name: 'native-guard',
     apply(ctx: Context) {

packages/core/agent-loop/tests/loop.spec.ts

@@ -183,11 +183,7 @@ describe('agent loop', () => {
   })
 
   it('contains a strict-variable render failure: the turn errors, the loop keeps serving turns', async () => {
-    // A persona claiming {{cwd}} on a session with NO cwd is a deployment
-    // authoring error — renderPrompt throws, the turn ends with an error, and
-    // the same agent must then RUN a later turn to completion (not merely
-    // report idle status): a rescue listener supplies the variable and the
-    // follow-up prompt reaches the model.
+    // A missing cwd variable must fail one turn without preventing a later valid turn.
     const adapter = new MockAdapter([textResponse('ok after rescue')])
     const ctx = await harness(adapter, 'In {{cwd}}.')
     const errors: Error[] = []
@@ -522,9 +518,8 @@ describe('agent loop', () => {
   })
 
   it('agent/pre-step fires BEFORE the step it precedes opens (events land outside the step)', async () => {
-    // A listener appending a surface node in pre-step lands it BEFORE step/start
-    // in the log — proving the seam fires outside the step. The node is still in
-    // the derived request for that step (derive happens after step/start).
+    // The append lands before step/start, yet derive happens afterwards and the
+    // same step's request must include it.
     const adapter = new MockAdapter([textResponse('ok')])
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
@@ -557,10 +552,8 @@ describe('agent loop', () => {
   })
 
   it('a throwing agent/pre-step listener ends the turn (error), not the loop', async () => {
-    // The seam fires before step/start, so a throw escapes to runTurn's outer
-    // catch: the not-yet-open step closes as a no-op, the failure surfaces via
-    // agent/error, and the turn ends `error` (recorded on the durable turn/end).
-    // The loop survives and a follow-up prompt still runs.
+    // Before step/start, a pre-step throw reaches the turn catch: no step needs
+    // closing, the turn records error, and the loop remains available.
     const adapter = new MockAdapter([textResponse('second turn ok')])
     const ctx = await harness(adapter)
     const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
@@ -627,16 +620,14 @@ describe('agent loop', () => {
 
     expect(adapter.requests).toHaveLength(1)
     expect(reasons).toEqual([{ kind: 'max-tokens' }])
-    // and the reason is recorded in the log's turn/end event
+    // Assert the durable row, not only the live listener.
     const turnEnd = agent.session.events.findLast(e => e.type === 'turn/end')
     expect(turnEnd!.data.reason).toEqual({ kind: 'max-tokens' })
   })
 
   it('a max-tokens step earlier in a turn still surfaces as max-tokens after a later completed step', async () => {
-    // Step 1 is cut off (max-tokens, no tool calls → would stop by default), so
-    // continuation must be FORCED to reach step 2 which finishes normally
-    // (stop). The rule "any max-tokens step surfaces as max-tokens" means the
-    // turn ends max-tokens even though the LAST step completed cleanly.
+    // Step 1 is cut off (max-tokens, no tool calls → would stop by default), so continuation
+    // must be FORCED to reach step 2 which finishes normally (stop).
     const adapter = new MockAdapter([
       maxTokensResponse('first half'),
       textResponse('second half'),
@@ -718,11 +709,8 @@ describe('agent loop', () => {
     expect(agent.session.events.some(e => e.type === 'tool/call')).toBe(false)
     expect(agent.session.deriveMessages()).toEqual([{ role: 'user', content: [{ type: 'text', text: 'go' }] }])
     expect(reasons).toEqual([{ kind: 'max-tokens' }])
-    // No-data-loss: a max-tokens step whose only content was a dropped tool call
-    // has EMPTY assistant content, but its usage must still be represented. It
-    // rides on an (empty-content) assistant/message — there is no standalone
-    // usage event — and that empty message is skipped by deriveMessages(), so
-    // the derived history above is NOT corrupted by a spurious assistant turn.
+    // Empty content still needs an assistant/message to carry usage; derivation
+    // skips that host so it does not create a spurious assistant turn.
     const assistantMessage = agent.session.events.find(e => e.type === 'assistant/message')
     expect(assistantMessage?.type === 'assistant/message' && assistantMessage.data).toEqual({
       turn: 1, step: 1, content: [], usage: { inputTokens: 10, outputTokens: 5 },
@@ -730,10 +718,9 @@ describe('agent loop', () => {
   })
 
   it('appends no assistant/message for a max-tokens step with empty content and no usage', async () => {
-    // A max-tokens step truncated to a dropped tool call AND with no usage chunk
-    // has nothing to record: empty content and no accounting → no assistant/message
-    // (the empty-content host exists only to carry usage). The turn still ends
-    // max-tokens.
+    // A max-tokens step truncated to a dropped tool call AND with no usage chunk has nothing to
+    // record: empty content and no accounting → no assistant/message (the empty-content host
+    // exists only to carry usage).
     const callId = CallId('c1')
     const adapter = new MockAdapter([[
       { type: 'block-start', index: 0, blockType: 'tool-call' },

packages/core/agent-loop/tests/properties.spec.ts

@@ -1,12 +1,7 @@
 /**
- * Property-based tests for the agent loop's inbox/turn scheduling (the
- * property-testing RFC). Deterministic by construction: schedules are driven
- * through the `agent/status` settle signal (no wall-clock sleeps), so a flake
- * is a finding, not timing noise.
- *
- * Invariants: every sent message appears exactly once in the log (none lost);
- * turn numbers strictly increase; status transitions follow the legal machine
- * idle→running→idle (and →disposed at teardown).
+ * Deterministic property tests for inbox scheduling: every sent message logs
+ * once, turn numbers increase, and status follows idle→running→idle/disposed.
+ * Schedules advance on status events rather than wall-clock sleeps.
  */
 
 import { describe, expect, it } from 'vitest'
@@ -146,10 +141,8 @@ describe('agent loop scheduling properties', () => {
         const ctx = await harness()
         try {
           const agent = ctx.agentLoop.create(AgentId('a'), { model: 'mock' })
-          // Capture an idle waiter before EACH send; the last one is guaranteed
-          // to resolve because the final send always triggers (or joins) a turn
-          // that ends idle. Awaiting an already-resolved waiter is a no-op, so a
-          // trailing settle step can't cause a hang.
+          // Capture before each send; the last waiter covers the final turn, and
+          // awaiting an already-settled earlier waiter is harmless.
           let lastIdle: Promise<void> | undefined
           for (const step of steps) {
             const idle = nextIdle(ctx, agent)

packages/core/agent-loop/tests/request-cache.e2e.ts

@@ -9,15 +9,13 @@ import AgentLoop from '@deepseek-ai/dsh-agent-loop'
 import * as LlmDeepSeek from '@deepseek-ai/dsh-llm-deepseek'
 
 /**
- * With-key proof that log-derived requests translate into REAL provider cache
- * hits: a multi-step tool turn (plus a follow-up turn) against the live
- * DeepSeek API must report `cacheReadTokens > 0` on every request after the
- * first — the adapter maps the provider's `prompt_cache_hit_tokens`, and the
- * per-step usage recorded on `assistant/message` events is the production
- * observable for cache behavior (the reconstructability RFC's measurement
- * layer: prefix stability is corollary #1). Mocks prove the requests are
- * append-extensions; only the real API proves those bytes actually hit the
- * provider cache. Key-gated — skips entirely without $DEEPSEEK_API_KEY.
+ * With-key proof that log-derived requests translate into real provider cache hits: a
+ * multi-step tool turn (plus a follow-up turn) against the live DeepSeek API must report
+ * `cacheReadTokens > 0` on every request after the first — the adapter maps the provider's
+ * `prompt_cache_hit_tokens`, and the per-step usage recorded on `assistant/message` events is
+ * the production observable for cache behavior (the reconstructability RFC's measurement
+ * layer: prefix stability is corollary #1). Mocks establish append-extension;
+ * this key-gated test establishes a real provider cache hit.
  */
 
 // Long enough that the shared request prefix comfortably spans the provider's

packages/core/agent-loop/tests/request-reconstruction.spec.ts

@@ -1,11 +1,9 @@
 /**
- * Loop-level reconstructability: every request the loop sends is a pure
- * function of the session log — messages are the derivation at the step/start
- * boundary, the header is the fold of request/header* events — and every
- * request is an append-extension of its predecessor unless a logged event
- * (compaction replace, header change) explains the difference. The requests
- * recorded by the mock adapter are the observable; the offline-rebuild test
- * at the bottom is the theorem stated end-to-end.
+ * Loop-level reconstructability: every request the loop sends is a pure function of the
+ * session log — messages are the derivation at the step/start boundary, the header is the fold
+ * of request/header* events — and every request is an append-extension of its predecessor
+ * unless a logged event (compaction replace, header change) explains the difference. Mock-adapter
+ * requests are the observable, and the final offline rebuild states the full contract end to end.
  */
 
 import { describe, expect, it } from 'vitest'

packages/core/agent-loop/tests/resume.spec.ts

@@ -460,10 +460,8 @@ describe('the session-persistence RFC: AgentLoop factory create/resume', () => {
   })
 
   it('an idle inject() is flushed durably on its own (survives without explicit flush/dispose)', async () => {
-    // Lifecycle 1: run a turn, then inject context while idle. The idle inject
-    // wraps its context/message in a one-shot turn AND checkpoints it (the turn-enclosure RFC)
-    // — without an explicit flush or clean dispose, the notice must still reach
-    // disk, since a crash before the next turn would otherwise lose it.
+    // Idle injection creates and flushes a one-shot turn. No explicit flush or
+    // clean disposal follows, so disk presence proves its own checkpoint ran.
     const adapter1 = new MockAdapter([textResponse('answer')])
     const { ctx: ctx1, root } = await persistentHarness(adapter1)
     const a1 = (await ctx1.agents.create({ agentId: AgentId('m'), sessionId: SessionId('inject-sess'), meta: { cwd: '/w' } })).agent as ReactLoopAgent
@@ -485,10 +483,8 @@ describe('the session-persistence RFC: AgentLoop factory create/resume', () => {
   })
 
   it('an idle inject() survives persist + resume (turn-enclosed, not dropped as crash tail)', async () => {
-    // Lifecycle 1: run a turn, then inject context while idle. The idle inject
-    // wraps its context/message in a one-shot turn so it is turn-enclosed —
-    // otherwise scanLog would treat the trailing context as a crash tail and
-    // drop it on reload (the bug this guards).
+    // Turn enclosure keeps idle context out of crash-tail repair, so it must
+    // survive persistence and resume.
     const adapter1 = new MockAdapter([textResponse('answer')])
     const { ctx: ctx1, root } = await persistentHarness(adapter1)
     const a1 = (await ctx1.agents.create({ agentId: AgentId('m'), sessionId: SessionId('inject-sess'), meta: { cwd: '/w' } })).agent as ReactLoopAgent

packages/core/agent-loop/tests/scope-lifecycle.spec.ts

@@ -934,11 +934,9 @@ describe('agent scope lifecycle', () => {
       order.push(`session-still-stored=${ctx.sessions.get(SessionId('o1-s')) !== undefined}`)
     })
 
-    // Open a turn so the drain has real work: the loop must finish it BEFORE
-    // the registry entry goes away (the agent/disposed contract: "its fiber
-    // and any in-flight turn have been torn down"). Wait for the turn to be
-    // OPEN in the log — a dispose landing in the pre-step window would drop
-    // the queued prompt without ever opening a turn.
+    // Open a turn so disposal must drain real work before registry removal.
+    // Waiting for turn/start avoids pre-step disposal dropping the queued prompt
+    // before a turn opens.
     const turnOpen = new Promise<void>((resolve) => {
       const off = ctx.on('session/event', (_s, event) => {
         if (event.type === 'turn/start') { off(); resolve() }

packages/core/agent-loop/tests/tool-order.spec.ts

@@ -1,10 +1,9 @@
 /**
- * Loop-level tool-order determinism: the request/header event — and therefore
- * the frozen request the adapter receives — carries the assembly's canonical
- * tool order (system-prompt's `toolOrder` config, or lexicographic name
- * order), regardless of the order tool plugins happened to register in.
- * Registration order is a plugin-load artifact (concurrent dynamic imports
- * race), so nothing downstream of the registry may depend on it.
+ * Loop-level tool-order determinism: the request/header event — and therefore the frozen
+ * request the adapter receives — carries the assembly's canonical tool order (system-prompt's
+ * `toolOrder` config, or lexicographic name order), regardless of the order tool plugins
+ * happened to register in. Registration order is a concurrent loading artifact
+ * and must not leak downstream.
  */
 
 import { describe, expect, it } from 'vitest'
@@ -93,11 +92,7 @@ describe('loop-level canonical tool order', () => {
   })
 
   it('fails the turn — no model request — when toolOrder names an unregistered tool', async () => {
-    // The assemble rejection escapes to runTurn's outer catch: the open turn
-    // closes with an `error` reason (agent/error mirrors it), no step opens,
-    // no request/header is logged, the adapter never sees a request, and the
-    // agent returns to idle — a misconfigured deployment fails every turn
-    // deterministically instead of silently reordering nothing.
+    // Unknown tool order fails before step or request creation and returns the agent to idle.
     const adapter = new MockAdapter([textResponse('never sent')])
     const ctx = await harness(adapter, ['ghost', TOOL_ORDER_REST])
     registerNamed(ctx, 'alpha')

packages/core/agent/README.md

@@ -8,28 +8,28 @@ Tracks live agents so UI, hook, and orchestrator plugins can find them without i
 
 ### Public API
 
-The scoped-registration surface: `Agent.ctx` is the agent's scope context (`dsh-scope`, key = the agent) — register tools/sections/variables/listeners through it for that agent alone, all unwound on disposal. `agentEvents(ctx, agent)` is the fused dispatcher for ordinary agent-subject operations (carrier + injected subject in one move); its notification mode invokes every listener and contains both synchronous throws and returned-promise rejections. The registry lifecycle pair reuses one stable routing carrier. `assembleContextFor(agent)` builds the per-agent assembly context (`agent` + `scope` together). `CreateAgentOptions.setup(agentCtx)` and `ResumeAgentOptions.setup(agentCtx)` compose a fresh or resumed agent's scoped world while both objects remain unpublished. Setup is trusted, composition-only same-process code: drive the agent only after creation resolves.
+`Agent.ctx` owns registrations visible only to that agent. `agentEvents()` couples event subjects to their scope carrier, and `assembleContextFor()` couples the agent and prompt scope. Creation and resume may compose this context through `setup`; the agent remains unpublished and must not be driven until creation resolves.
 
 - `ctx.agents.register(agent: Agent): () => void` — record an **already-constructed** agent. Disposed with the calling fiber.
-- Advanced ordered lifecycle: `enter(agent): () => void` performs the authoritative ID collision check and inserts without announcing; `announce(agent)` emits `agent/created` exactly once. A detach requested synchronously by a creation listener is deferred until that dispatch unwinds, and every detach checks the captured entry object, so a stale capability cannot delete a later same-ID replacement. The async factory uses this split; ordinary plugins use `register()`.
+- Advanced factory lifecycle: `enter(agent)` publishes without announcing and returns an entry-bound detach; `announce(agent)` emits creation once. Detach during creation dispatch is deferred. Ordinary plugins use `register()`.
 - `ctx.agents.get(id: AgentId): Agent | undefined`
 - `ctx.agents.list(): Agent[]`
 
 #### Factory seam (creation)
 
-Agent *creation* is provided by the plugin implementing `AgentFactory` (`dsh-agent-loop`), registered via `setFactory`. This keeps creation on the `dsh-agent` interface so consumers (UI, the ACP bridge) program against `ctx.agents` without depending on the concrete loop package. The registry canonicalizes an already traced Service to its concrete target and re-traces each call through the caller's context; this avoids nested Cordis shadows while passing an explicit caller-bound `ownerCtx` to plain factories.
+The loop plugin registers `AgentFactory`, keeping consumers independent of its concrete package. Each call is traced through the caller's context so the caller owns the resulting transaction and handle.
 
 - `ctx.agents.setFactory(factory: AgentFactory): () => void` — register the creation factory (the loop calls this on construction). Throws on a second factory; the slot clears on dispose.
-- `ctx.agents.create(options: CreateAgentOptions): Promise<AgentHandle>` — create a session and agent, await optional setup while unpublished, then publish through final `SessionStore.enter()` and `AgentRegistry.enter()` checks. Concurrent same-ID creation is unsupported: more than one operation may prepare, but only one can enter; every loser rolls its private scope/session/driver back. An optional creation-only `signal` cancels unpublished setup and is detached before the handle is returned; later cancellation uses `handle.dispose()` or `agent.cancel()`. Publication is rollback-covered and every delivered creation edge is paired during rollback. Rejects if no factory is registered.
-- `ctx.agents.resume(options: ResumeAgentOptions): Promise<AgentHandle>` — load a persisted session ([session persistence](../../../docs/rfc/implemented/architecture/2026-06-14-session-persistence.md)), mint a fresh unpublished agent scope, await optional setup, and use the same final-entry publication sequence. Its optional `signal` is likewise creation-only. Rejects if no factory is registered or session persistence is unconfigured.
+- `ctx.agents.create(options)` creates and composes an unpublished session and agent, then atomically enters the registries and starts the loop. A creation-only signal cancels before publication; same-ID contenders arbitrate at entry and losers roll back.
+- `ctx.agents.resume(options)` loads a persisted session and follows the same composition and publication boundary. It requires [session persistence](../../../docs/rfc/implemented/architecture/2026-06-14-session-persistence.md).
 
-`AgentHandle = { agent: Agent; dispose(): Promise<void> }`. The disposer is a **consumer capability** — no observer holding the bare registry entry can tear the agent down. The caller fiber and the registered factory provider are structural co-owners: caller unload enforces structured ownership, while factory unload must stop old instances because their scoped dependency surface belongs to that provider. `dispose()` from any owner reaches one memoized quiescence boundary: it stops the loop, `await`s its exit plus every outstanding idle-injection flush (not just the `disposed` status flip), unregisters the agent, removes its session from the store, and finally unwinds its scoped world. This order captures every agent-started `session/flush` before the session is detached and keeps scoped listeners alive through those checkpoints. `ctx.agents.get(id)` still returns a bare `Agent`; the ACP bridge and in-process subagent backends hold consumer handles, while config-created agents are already owned by the loop fiber.
+`AgentHandle = { agent, dispose }` is the consumer teardown capability; registry observers receive only the bare agent. Disposal stops and drains the loop and idle-injection flushes before unregistering the agent, detaching its session, and unwinding its scope. Caller and factory unload share that memoized boundary.
 
 ### Live events
 
 `dsh-agent` declares the live `agent/*` coordination vocabulary so plugins do not depend on the concrete loop. Exact signatures, dispatch modes, scope-filtering rules, and payload contracts live in the generated [Cordis event catalog](../../../docs/cordis-catalog/events.md); the [architecture turn flow](../../../docs/architecture.md#turn-flow) shows their order relative to durable session events.
 
-The lifecycle edges have two important local caveats. `agent/created` runs after scoped setup and after both session and agent registry entries exist. Setup is trusted composition-only code; the immediately following non-vetoing `agent/session-start` notification is the first supported startup injection point. `agent/disposed` always means the exact agent has left the registry. AgentLoop emits it after its driver is quiescent, while ordered teardown may still be detaching the session and unwinding the scope; custom agents registered directly own any stronger driver-ordering contract themselves.
+`agent/created` runs after setup and both registry entries; the following `agent/session-start` is the first supported startup injection point. `agent/disposed` means the exact entry left the registry. The loop quiesces its driver first; directly registered custom agents own any stronger ordering.
 
 Most interception points are cooperative waterfalls returning seam-specific decisions. `agent/pre-step` is a serial surface-mutation checkpoint, while `agent/turn-stop` is the terminal serial fold: it runs after ordinary continuation and steering folding, and a returned stop remains in force through turn close and flush so later steering cannot create an extra step or turn. Ordinary queued prompts remain intact. The full rationale is in the [agent-scope runtime-design RFC](../../../docs/rfc/implemented/architecture/2026-07-12-agent-scope-runtime-design.md#three-execution-boundaries-are-deliberately-one-way).
 
@@ -73,4 +73,3 @@ The handle every plugin programs against:
 - **No public step-only abort** — `cancel()` clears ALL pending work (queued + steering + in-flight); an abort that preserves queued prompts returns only with a named consumer ([stop-surface RFC](../../../docs/rfc/implemented/simplification/2026-06-20-public-agent-stop-surface.md)).
 - **`HookContext` carries exactly one `MessageSource`** — contributions from several plugins merged onto one tool call collapse under one source; mixed provenance is unrepresentable.
 - **`SessionStartSource` reserves `'clear'`/`'compact'` with no emitter yet** — only `'startup'`/`'resume'` occur until the driving subsystems land (`TODO(compaction)`).
-- **`agent/pre-step`'s `fullSystemPrompt`/`sessionPrefix` parameters are a flagged smell** — compaction is their only consumer; a lazy prompt provider or a compaction-specific pressure seam is the marked revisit.

packages/core/agent/src/dispatch.ts

@@ -1,14 +1,7 @@
 /**
- * Fused scope-carrier dispatch for agent-subject operations, plus the assembly
- * context builder. The sanctioned ordinary spelling is
- * `agentEvents(ctx, agent).waterfall('agent/request', …)`: it builds the scope
- * carrier ({@link scopeTarget} keyed by the agent) AND injects the subject as
- * the first argument in one move, so a site cannot name a different subject.
- * The registry lifecycle pair is the deliberate exception: `enter()` captures
- * one stable carrier before commit and `announce()`/detach dispatch through it
- * directly, so both lifecycle edges use the same routing identity. The dev
- * scoped-dispatch invariant checks both shapes.
- *
+ * Agent-scoped dispatch and prompt assembly helpers. Ordinary events use the
+ * fused dispatcher so subject and scope key cannot diverge; registry lifecycle
+ * code instead captures one stable carrier for both edges.
  * @module @deepseek-ai/dsh-agent/dispatch
  */
 
@@ -74,9 +67,7 @@ export interface AgentEventDispatch {
 }
 
 /**
- * Build the fused dispatcher for `agent`'s events (see the module doc). Cheap
- * (one carrier + one small object) — dispatch sites create it per run/turn
- * rather than caching it on the agent.
+ * Build a dispatcher that couples the agent subject to its scope carrier.
  * @param ctx - the context to dispatch through (any context of the app).
  * @param agent - the subject agent; also the scope-carrier key.
  * @returns the fused dispatcher.
@@ -121,11 +112,8 @@ export function agentEvents(ctx: Context, agent: Agent): AgentEventDispatch {
 }
 
 /**
- * The assembly context for one agent's prompt: the typed `agent` DX field and
- * the `scope` layer selector, set together (setting `agent` without `scope`
- * silently drops the agent's scoped sections/tools from the assembly — the
- * dev invariants flag it). THE way the loop (and any custom driver) builds
- * its per-step `ctx.systemPrompt.assemble(…)` input.
+ * Build the prompt assembly context with agent and scope set together, so
+ * agent-scoped prompt and tool contributions cannot be silently omitted.
  * @param agent - the agent the assembly is for.
  * @returns the context to pass to `assemble()`.
  */

packages/core/agent/src/index.ts

@@ -31,59 +31,23 @@ declare module 'cordis' {
   }
 }
 
-/**
- * Options for programmatically creating an agent through the registry factory
- * ({@link AgentRegistry.create}). The caller supplies the live `sessionId`
- * (e.g. an ACP-generated id) and optional session metadata (the validated
- * `cwd`, fork lineage); the factory creates the session, the agent, and wires
- * them together.
- */
+/** Options for creating an agent and its caller-named session. */
 export interface CreateAgentOptions {
   /** The agent's id (the registry handle). */
   readonly agentId: AgentId
   /** The live session's id (NOT derived from agentId). */
   readonly sessionId: SessionId
-  /**
-   * Session creation metadata: validated absolute `cwd`, `parentSession`
-   * fork lineage, and the `seedLength` seed boundary. Mirrors the
-   * `cwd`/`parentSession`/`seedLength` fields of
-   * {@link CreateSessionOptions.meta} in dsh-session (the internal-only
-   * `createdAt`, used when reconstructing a persisted session, is deliberately
-   * excluded — a factory caller never sets it). This is durable session data,
-   * so the session boundary validates and snapshots it before asynchronous
-   * setup begins.
-   */
+  /** Durable session metadata, validated and detached before setup. */
   readonly meta?: { readonly cwd?: string; readonly parentSession?: SessionId; readonly seedLength?: number }
-  /**
-   * Seed events to reconstruct the child session's log from (the fork lineage
-   * primitive). When present, the factory creates the session with this event
-   * prefix so `deriveMessages()`/`lastTurnNumber` continue from it — used by the
-   * in-process FORK subagent backend to seed a child with a balanced
-   * completed-turn prefix of the parent's log. The prefix MUST be contiguous
-   * from seq 0, carry only lossless-JSON data, and be balanced (no open
-   * turn/step, no dangling tool-call), or the session constructor (and the
-   * dev-mode invariants replay) reject it. The factory passes the raw seed to
-   * the session's durable validator/snapshot boundary. Absent for a fresh
-   * (spawn) child.
-   */
+  /** Balanced contiguous event prefix for a forked session. */
   readonly seed?: readonly SessionEvent[]
   /** Per-agent options (model, …). */
   readonly agentOptions?: AgentOptions
   /** Optional creation-only cancellation signal; detached before the returned handle becomes visible. */
   readonly signal?: AbortSignal
   /**
-   * Creation-time composition of the agent's scoped world. The factory awaits
-   * setup after minting `agentCtx` but BEFORE inserting or announcing either
-   * the session or agent, so observers can never see a partially configured
-   * world. Everything registered through `agentCtx` (scoped tools, prompt
-   * sections/variables, `restrict()`, listeners, awaited child plugins) exists
-   * before `session/created`, `agent/created`, `agent/session-start`, and the
-   * first prompt assembly. A throw/rejection or owner disposal rolls the scope
-   * back without publishing either id.
-   *
-   * **Setup composes, it never drives**: the callback is trusted same-process
-   * code and receives the full scoped context, so this is a contract rather
-   * than a runtime restriction. Drive the agent only after creation resolves.
+   * Compose the unpublished scoped context before lifecycle announcements.
+   * Failure rolls back without publishing either id; setup must not drive the agent.
    */
   readonly setup?: (agentCtx: Context) => Promise<void> | void
 }
@@ -101,35 +65,15 @@ export interface ResumeAgentOptions {
   readonly agentOptions?: AgentOptions
   /** Optional creation-only cancellation signal for persistence load/setup; detached before return. */
   readonly signal?: AbortSignal
-  /**
-   * Resume-time composition of the agent's fresh scoped world. Persistence is
-   * loaded first; the factory then mints `agentCtx` and awaits setup while the
-   * reconstructed session and agent remain unpublished. The callback has the
-   * same trusted composition-only contract as
-   * {@link CreateAgentOptions.setup}: all registrations exist before either
-   * creation announcement, and rejection or owner disposal rolls the
-   * transaction back without publishing either id.
-   */
+  /** Compose after persistence load under the same unpublished rollback contract as create. */
   readonly setup?: (agentCtx: Context) => Promise<void> | void
 }
 
 /**
- * An owned agent plus its disposer, returned by {@link AgentRegistry.create} /
- * {@link AgentRegistry.resume}. The disposer is a CAPABILITY: among consumers,
- * only the holder can tear this agent down. The registered factory provider is
- * also a structural owner because the scoped agent depends on that provider's
- * service surface; provider unload stops and drains every live handle it made.
- * `dispose()` stops the loop, awaits its exit and every outstanding
- * idle-injection flush (quiescence — NOT just the `disposed`
- * status flip), unregisters the agent, removes its session from the store, and
- * finally unwinds its scoped world. This order captures every agent-started
- * `session/flush` before the session is detached and keeps scoped listeners
- * alive through those checkpoints.
- *
- * `ctx.agents.get(id)` still returns a bare {@link Agent} — the handle is
- * exposed only to the consumer owner that created it; the structural provider
- * reaches the same teardown internally. Config-created agents (the loop's own
- * startup) are owned by the loop fiber and never need a handle.
+ * Holder-owned agent capability. Disposal stops and drains the loop and idle
+ * flushes before unregistering the agent, detaching its session, and unwinding
+ * its scoped context. Provider unload reaches the same quiescence boundary;
+ * registry observers receive only the bare {@link Agent}.
  */
 export interface AgentHandle {
   agent: Agent
@@ -144,30 +88,16 @@ export interface AgentHandle {
  */
 export interface AgentFactory {
   /**
-   * Create a new agent on a caller-supplied session id. Async because creation
-   * awaits unpublished setup, inserts both session and agent, emits their
-   * creation notifications in order, emits `agent/session-start`, and only
-   * then starts the loop. The sequence is
-   * rollback-covered, but notifications delivered before a later listener
-   * failure remain observable; every agent or session creation announcement
-   * that began is paired by `agent/disposed` or `session/disposed` during
-   * rollback. The owner disposes the resolved handle to stop/drain,
-   * unregister, remove the session, and unwind the scope.
-   * The registry passes a context carrying the `create()` caller's fiber and
-   * scope as `ownerCtx`. The implementation attaches the unpublished
-   * transaction and resulting lifecycle to that owner; it must not infer
-   * ownership from the factory object's registration context.
+   * Create and compose under caller ownership, publish and announce session then
+   * agent, emit session-start, and start the driver. Rollback pairs any creation
+   * announcement that began.
    * @param ownerCtx - caller-bound context that owns the transaction and live handle.
    * @param options - agent/session identity, configuration, and optional setup.
    * @returns the owned handle after setup, both announcements, and loop start complete.
    */
   createAgent(ownerCtx: Context, options: CreateAgentOptions): Promise<AgentHandle>
   /**
-   * Load a persisted session and resume an agent on it. Async because it awaits
-   * both `ctx.sessionPersistence.load` and the optional unpublished setup
-   * transaction; must be called after that service exists (consumers inject
-   * `sessionPersistence`). Publication follows the same ordered boundary as
-   * {@link createAgent}.
+   * Load, compose, publish, announce, and resume an agent under caller ownership.
    * @param ownerCtx - caller-bound context that owns load, setup, and the live handle.
    * @param options - persisted identity, configuration, and optional setup.
    * @returns the owned handle after setup, both announcements, and loop start complete.
@@ -209,41 +139,25 @@ export class AgentRegistry extends Service {
 
   constructor(ctx: Context) {
     super(ctx, 'agents')
-    // The `ctx.agent` DX accessor: default `undefined` on every context, so a
-    // plain plugin context reads cleanly instead of hitting the Cordis
-    // unknown-property throw. Each Agent.ctx shadows it with an own property
-    // (own properties resolve before the context proxy is consulted), so the
-    // accessor body never needs to resolve a scope itself. Effect-scoped:
-    // unwinds with this service's fiber.
+    // Agent contexts shadow this plain-context default with an own property.
     ctx.accessor('agent', { get: () => undefined })
   }
 
   /**
-   * Register the agent-creation factory (the loop calls this on construction,
-   * effect-scoped). A traced Cordis service is canonicalized to its concrete
-   * target; each create/resume call is then traced through that caller's
-   * context so ownership follows the caller without stacking proxy layers.
-   * Throws if a factory is already registered. Returns the disposer; on
-   * dispose the factory slot is cleared.
+   * Register the effect-scoped creation factory, rejecting a duplicate. Service
+   * factories are retraced through each create/resume caller for ownership.
    * @param factory - the loop-owned factory {@link create}/{@link resume} delegate to.
-   * @returns the disposer that clears the factory slot. The exact
-   *   Cordis effect disposer (single-shot): composite (generator) effects may
-   *   yield it directly — exact identity nests the teardown in order.
+   * @returns the exact Cordis effect disposer.
    */
   setFactory(factory: AgentFactory): () => void {
     const dispose = this.ctx.effect(() => {
       if (this.factory !== undefined) throw new Error('an agent factory is already registered')
-      // Avoid stacking two Cordis shadow layers when a caller passes a Service
-      // already read through a context. Calls are re-traced through their
-      // actual owner context below.
+      // Store the concrete service; calls are retraced through their owner.
       const target = (factory as AgentFactory & { [symbols.original]?: AgentFactory })[symbols.original] ?? factory
       this.factory = { target }
       return () => { this.factory = undefined }
     }, 'agents.setFactory()')
-    // The exact cordis effect disposer (the agents.register() convention): a
-    // caller's composite effect can yield it for in-order teardown; the
-    // loop's constructor effect returns it directly, identity-nesting the
-    // registration under that effect.
+    // Return the exact disposer so composite effects preserve teardown order.
     // eslint-disable-next-line @typescript-eslint/no-misused-promises -- synchronous cleanup; direct return preserves disposer identity
     return dispose
   }
@@ -255,20 +169,14 @@ export class AgentRegistry extends Service {
   }
 
   /**
-   * Create and publish a new agent through the registered factory.
-   * Distinct from {@link register} (which records an already-constructed
-   * agent): this constructs the agent and its session. Rejects if no factory is
-   * registered or creation/setup fails. The resolved {@link AgentHandle} lets
-   * the owner tear down exactly this agent.
+   * Create and publish an owned agent and session through the active factory.
+   * Rejects if no factory is registered or creation, setup, or publication fails.
    * @param options - agent id, session id/seed/metadata, and agent options.
    * @returns the handle after setup, rollback-covered publication, and loop start complete.
    */
   async create(options: CreateAgentOptions): Promise<AgentHandle> {
     const ownerCtx = this.ctx
-    // Re-trace a Service-backed factory through the accessing context
-    // explicitly. This preserves AgentLoop's dependency origin while binding
-    // its effects to ownerCtx; plain factories receive ownerCtx as an explicit
-    // capability and need no Cordis tracker magic.
+    // Bind service effects to this caller while preserving factory dependencies.
     const { target } = this.requireFactory()
     const receiver = getTraceable(ownerCtx, target)
     // eslint-disable-next-line @typescript-eslint/unbound-method -- Reflect.apply intentionally supplies the caller-traced receiver
@@ -291,22 +199,10 @@ export class AgentRegistry extends Service {
   }
 
   /**
-   * Register a live agent. Throws if an agent with the same id is already
-   * registered. Emits `agent/created` on registration and `agent/disposed`
-   * when the calling fiber is disposed — both with the agent's scope carrier
-   * (`scopeTarget(agent, agent)`): the subject is the agent in hand, so the
-   * emits are scope-filtered regardless of which context invoked `register`
-   * (calling through `agent.ctx` scopes EFFECTS; dispatch scoping always
-   * requires passing the carrier). Returns the disposer.
+   * Register a live agent in the calling effect scope, with scope-filtered
+   * creation and disposal events. Duplicate ids throw.
    * @param agent - the already-constructed agent to record in the store.
-   * @returns the EXACT Cordis effect disposer (single-shot; a repeat call
-   *   returns undefined without awaiting an in-flight teardown). Exact
-   *   identity is load-bearing: a composite (generator) effect that owns a
-   *   teardown ORDER — the agent factory's lifecycle chain — must yield THIS
-   *   function so Cordis nests the unregistration at that yield position;
-   *   yielding a wrapper would leave it disposing as a concurrent sibling on
-   *   owner unload, unregistering the agent (and emitting `agent/disposed`)
-   *   while its final turn is still draining.
+   * @returns the exact Cordis effect disposer for nested teardown ordering.
    */
   register(agent: Agent): () => void {
     const dispose = this.ctx.effect(function* (this: AgentRegistry) {
@@ -318,22 +214,15 @@ export class AgentRegistry extends Service {
   }
 
   /**
-   * Insert an already-constructed agent without announcing it. This is the
-   * advanced ordered-lifecycle primitive used by the async agent factory: it
-   * first completes setup while the agent is unpublished, then assigns the
-   * returned detach closure into its pre-installed composite teardown before
-   * calling {@link announce}. Ordinary callers use {@link register}.
+   * Insert an unpublished agent for an ordered factory transaction.
    * @param agent - the prepared, unpublished agent.
-   * @returns an idempotent closure that removes this exact entry and emits
-   *   `agent/disposed` with listener failures contained. When called from a
-   *   synchronous `agent/created` listener, removal and disposal wait until
-   *   that creation dispatch unwinds.
+   * @returns an idempotent closure that removes this exact entry and emits the
+   * paired disposal edge; detachment during creation dispatch is deferred.
    */
   enter(agent: Agent): () => void {
     const id = agent.id
     const carrier = scopeTarget(agent, agent)
-    // This is the authoritative collision boundary. Concurrent create/resume
-    // operations may both prepare, but only one exact entry can publish.
+    // Prepared transactions arbitrate identity at this publication boundary.
     if (this.entries.has(agent) || this.store.has(id)) throw new Error(`agent "${id}" is already registered`)
     const entry: AgentEntry = {
       id,
@@ -349,11 +238,7 @@ export class AgentRegistry extends Service {
     const detach = (): void => {
       if (!entered) return
       entered = false
-      // Every callback reached by this creation dispatch must observe the same
-      // live entry, and disposal must follow creation. A listener may own
-      // the advanced detach capability, so make that ordering structural:
-      // visibility and the paired disposal are deferred until announce()'s
-      // synchronous dispatch has unwound.
+      // Creation listeners observe one stable entry before paired disposal.
       if (entry.announcing) {
         entry.detachRequested = true
         return

packages/core/agent/src/types.ts

@@ -1,46 +1,6 @@
 /**
- * Agent interface and event taxonomy. Every plugin programs against the
- * `Agent` handle defined here; the concrete implementation lives in
- * `@deepseek-ai/dsh-agent-loop`.
- *
- * Merge-extensible: `AgentOptions` supports declaration merging for
- * plugin-specific creation options.
- *
- * ## Event-domain semantics (the boundary rule)
- *
- * The harness has three event domains, each with one job:
- *
- * - **`session/*`** (`@deepseek-ai/dsh-session`) — the DURABLE, replayable FACT
- *   log. Owns `SessionEventMap`; every entry is JSON-only (no live objects).
- *   One `session/event` emit per append, plus the `session/flush` parallel
- *   durability checkpoint. Answers "what happened, durably/replayably." A
- *   consumer that wants the live transcript subscribes here.
- * - **`agent/*`** (this module) — the LIVE runtime surface. Always carries the
- *   live `Agent`. Two shapes: INTERCEPTION seams (the `agent/prompt-submit`/
- *   `agent/request`/`agent/session-prefix`/`agent/step-result`/
- *   `agent/turn-continuation` waterfalls and the serial `agent/pre-step` /
- *   `agent/turn-stop` checkpoints) that mutate/veto, and TRANSIENT emits
- *   (`agent/status`, `agent/error`, `agent/created`/
- *   `agent/disposed`, `agent/queued`, `agent/session-start`)
- *   that notify with the `Agent` in hand. Turn/step boundaries are NOT here —
- *   they are durable `session/event` records. Answers "right now, with the agent
- *   object — intercept or observe."
- * - **`tools/*`** (`@deepseek-ai/dsh-tools`) — the tool registry + execution.
- *
- * **The rule:** a durable, replayable fact is a SessionEvent; a live
- * interception or a transient/live-object signal is an `agent`/`tools` Cordis
- * event. A turn/step boundary is a durable fact: it lives in the session log
- * and is read off the `session/event` feed — it is NOT mirrored as an `agent/*`
- * emit. A consumer that needs the `Agent` handle (or its short id) at a boundary
- * keeps a session-id→agent map from `agent/created`/`agent/disposed`.
- * See `docs/rfc/implemented/architecture/2026-06-11-microkernel-event-taxonomy.md`
- * and `docs/rfc/implemented/simplification/2026-06-20-remove-agent-boundary-mirror-events.md`.
- *
- * The interception waterfalls here (`agent/prompt-submit`, `agent/request`,
- * `agent/step-result`, `agent/turn-continuation`) each return a typed Decision;
- * the terminal serial `agent/turn-stop` returns the stop-only subset. The
- * convention is pinned by
- * `docs/rfc/implemented/feature/2026-06-30-interception-seams.md`.
+ * Public agent types and live-runtime events. Durable transcript facts and
+ * turn/step boundaries remain `@deepseek-ai/dsh-session` events.
  *
  * @module @deepseek-ai/dsh-agent/types
  */
@@ -66,38 +26,18 @@ import type { Session } from '@deepseek-ai/dsh-session'
 
 declare module '@deepseek-ai/dsh-system-prompt' {
   interface AssembleContext {
-    /**
-     * The agent this assembly is for. The agent loop passes it on every
-     * per-step assembly (via its `assembleContextFor(agent)` helper, which
-     * also sets the `scope` field to the same agent — the layer selector
-     * `dsh-system-prompt` reads); variable providers project per-agent facts
-     * from it (`options.model` → `{{model}}`, `session.header.cwd` →
-     * `{{cwd}}`). Optional because a bare `assemble()` (tests, diagnostics)
-     * has no agent — providers must tolerate its absence. Never set `agent`
-     * without `scope`: the assembly would silently miss the agent's scoped
-     * sections/tools (the dev invariants flag it).
-     */
+    /** Agent for this assembly; absent on diagnostics. When present, `scope` must identify the same agent. */
     agent?: Agent
   }
 }
 
-/**
- * Options an agent is created with. The persona is NOT here: the
- * dsh-system-prompt config supplies the global default, and a scoped
- * `deployment:persona` section may override it for one agent.
- * Merge-extensible: plugins declare extra fields via declaration merging.
- */
+/** Merge-extensible agent creation options. Persona belongs to system-prompt sections. */
 export interface AgentOptions {
   /** Model name (must have a registered adapter at call time). */
   model?: string
 }
 
-/**
- * Options for {@link Agent.send}/{@link Agent.steer}/{@link Agent.inject}. An
- * absent `source` resolves to `{ kind: 'user' }`, so a plugin supplying content
- * must label itself here or its message is recorded as a user prompt (see
- * {@link HookContext} on why that label is load-bearing).
- */
+/** Message options; an omitted source resolves to `{ kind: 'user' }`, so plugins must label their own content. */
 export interface SendOptions {
   source?: MessageSource
 }
@@ -110,54 +50,22 @@ export interface SendOptions {
  */
 export type AgentStatus = 'idle' | 'running' | 'disposed'
 
-/**
- * Model-facing context an interception listener wants the agent to SEE on the
- * next request — the canonical shape behind every "inject extra context"
- * decision ({@link PromptDecision}, {@link PostToolDecision},
- * {@link ContinuationDecision}). It is `agent.inject()`ed as a
- * `context/message`, so it carries a REQUIRED {@link MessageSource}: `inject()`
- * defaults a missing source to `{kind:'user'}`, which would MISLABEL plugin
- * context as a user prompt and corrupt derived history. A bridge sets
- * `{kind:'plugin', plugin:'…'}`; a native plugin names itself. Required, not
- * optional — the label is load-bearing, never defaulted here.
- */
+/** Model-facing context injected by a listener; `source` prevents plugin text from being labeled as user input. */
 export interface HookContext {
   content: ContentBlock[]
   source: MessageSource
 }
 
 /**
- * The decision an {@link Agent} `agent/prompt-submit` waterfall listener returns
- * for ONE drained queued message, before it becomes a `user/message`. Maps onto
- * the Claude Code `UserPromptSubmit` hook's allow/block + `additionalContext`.
- *
- * - `allow` proceeds with the prompt; optional `content` REPLACES the prompt
- *   bytes (a rewrite), and optional `additionalContext` is `inject()`ed as a
- *   separate `context/message` the next request also sees.
- * - `block` drops the prompt (it never becomes a `user/message`); `reason` is
- *   the durable record of why. The loop appends a `prompt/blocked` session event
- *   (carrying the original content, source, and `reason`) in place of the
- *   dropped `user/message`, so the veto survives replay even in a MIXED batch
- *   where a sibling prompt is allowed. A batch whose EVERY prompt is blocked
- *   additionally opens a zero-step turn that ends with {@link TurnEndReason}
- *   `rejected` (so the boundary stays balanced and a UI can render "blocked by
- *   hook").
+ * Prompt interception result. `allow.content` replaces the prompt and
+ * `additionalContext` becomes a separate context message. `block` records a
+ * durable `prompt/blocked`; an all-blocked batch ends a zero-step rejected turn.
  */
 export type PromptDecision =
   | { kind: 'allow'; content?: ContentBlock[]; additionalContext?: HookContext }
   | { kind: 'block'; reason: string }
 
-/**
- * The decision an {@link Agent} `agent/turn-continuation` waterfall listener
- * returns. The loop computes the default (`continue` when the step had tool
- * calls or steering was injected, else `stop`); listeners override it to
- * force-continue (`/goal`, `/loop`) or force-stop (budget guards).
- *
- * A `continue` may carry a `reason`: model-facing context recorded as next-STEP
- * steering within the SAME turn (the loop enqueues it through the steering
- * channel, so the continued turn's next step sees it). This is the typed twin of
- * the existing "steer from a step/end listener" `/goal` pattern.
- */
+/** Turn continuation override; a continue reason is recorded as next-step steering in the same turn. */
 export type ContinuationDecision =
   | { action: 'stop' }
   | { action: 'continue'; reason?: HookContext }
@@ -169,47 +77,21 @@ export type ContinuationDecision =
  */
 export type ContinuationStop = Extract<ContinuationDecision, { action: 'stop' }>
 
-/**
- * Why an agent's session lifecycle began, carried by `agent/session-start`. A
- * bridge keys its SessionStart hook's matcher on this (Claude Code's
- * `startup`/`resume`/`clear`/`compact` source set). `startup` = a fresh create
- * (including a seeded/forked create — a seed is NOT a resume); `resume` = a
- * persisted session reloaded via `ctx.agents.resume()`. `clear`/`compact` are
- * driven by those subsystems (compact = `TODO(compaction)`).
- */
+/** Why a session lifecycle began; seeded creates are `startup`, while persisted loads are `resume`. */
 export type SessionStartSource = 'startup' | 'resume' | 'clear' | 'compact'
 
-/**
- * The agent handle — the surface every plugin (UI, hooks, orchestrators)
- * programs against. The concrete implementation lives in
- * `@deepseek-ai/dsh-agent-loop` (class `ReactLoopAgent`); nothing outside the loop
- * package should depend on the implementation.
- */
+/** Public agent handle; the concrete driver belongs to `@deepseek-ai/dsh-agent-loop`. */
 export interface Agent {
   readonly id: AgentId
   readonly options: AgentOptions
   readonly session: Session
   readonly status: AgentStatus
-  /**
-   * The agent's scope context (`@deepseek-ai/dsh-scope`, key = this agent).
-   * Registrations through it — tools, prompt sections/variables, event
-   * listeners, restrictions — are visible to THIS agent only and unwind when
-   * the agent is disposed; `agent.ctx.on('agent/…')` listeners fire only for
-   * this agent's dispatches (zero self-filtering). Service resolution through
-   * it flows through the loop plugin's dependency surface — handing out
-   * `agent.ctx` hands out that capability. Live for exactly the agent's
-   * lifetime: registrations after disposal throw Cordis's INACTIVE_EFFECT.
-   */
+  /** Agent-scoped context; its contributions are agent-local, unwind on disposal, and reject registration afterward. */
   readonly ctx: Context
 
   /**
-   * Queue a user message. Starts a turn when idle; otherwise waits for the next
-   * turn. Content and the resolved source are accepted as one detached,
-   * deeply-frozen lossless-JSON record before notification or enqueue, so
-   * caller or `agent/queued` listener in-place mutation cannot change later
-   * log/model input. Throws synchronously when either value is not losslessly
-   * JSON-serializable; `agent/prompt-submit` may still return an explicit
-   * replacement.
+   * Queue detached, frozen lossless-JSON input; starts a turn when idle.
+   * Invalid input throws synchronously before notification or enqueue.
    */
   send(content: ContentBlock[], options?: SendOptions): void
 
@@ -221,317 +103,137 @@ export interface Agent {
   steer(content: ContentBlock[], options?: SendOptions): void
 
   /**
-   * Inject in-session context (file-change notices, skill content, cron
-   * notifications, …): appends a `context/message` session event the next model
-   * request sees at its chronological position, rendered as tagged synthetic
-   * context rather than a user prompt. Does not run the model.
-   *
-   * Turn-enclosure (the turn-enclosure RFC): an inject while a turn is open joins that turn;
-   * an inject while idle wraps its `context/message` in a one-shot `injection`
-   * turn (`turn/start` → `context/message` → `turn/end`) and checkpoints it for
-   * durability, so every event stays inside a turn and a persistence backend
-   * never loses a between-turn notice. The idle checkpoint is fire-and-forget
-   * from this synchronous method, but lifecycle disposal awaits it before
-   * unregistering the agent or detaching its session. A failing flush is
-   * reported via `agent/error` (step `0`) and the logger, never thrown into the
-   * caller.
-   *
-   * Live-adapter review has validated the tagged-envelope rendering against
-   * current DeepSeek behavior; provider-specific mismatches belong in that
-   * adapter, not in the canonical session vocabulary.
+   * Append model-facing context without running the model. Idle injection uses
+   * a one-shot turn and durability checkpoint, while injection during an open
+   * turn joins it at the current log position. Disposal awaits idle checkpoints;
+   * flush failures are reported through `agent/error`, not thrown to the caller.
    */
   inject(content: ContentBlock[], options?: SendOptions): void
 
   /**
-   * Cancel ALL pending work for the agent. `cancel()`:
-   *
-   * - clears the queued FIFO (un-started prompts never run) and the steering
-   *   FIFO (steering for the cancelled turn is dropped, not re-enqueued);
-   * - aborts the in-flight step if one is running (the turn ends `aborted`);
-   * - drops a turn that is about to start (a `cancel()` landing in the
-   *   pre-step window — after a `send()` queued but before the loop flips to
-   *   `running`, or after `running` is emitted but before the first step) so
-   *   that queued prompt does not run and cannot be batched into the cancelled
-   *   turn.
-   *
-   * After `cancel()`, `whenIdle()` resolves on the post-cancel quiescent state.
-   * `cancel()` on an idle agent with nothing queued or running is a safe no-op
-   * — it does NOT arm anything that would drop a later legitimate prompt.
+   * Clear queued and steering work, including work waiting to start, and abort
+   * the active step. The supplied reason is preserved across pre-step and active
+   * cancellation windows, and `whenIdle()` resolves after cancellation reaches
+   * quiescence. Idle cancellation is a no-op and does not arm a later cancel.
    */
   cancel(reason?: string): void
 
-  /**
-   * Resolve once the agent has reached quiescence after settling out of
-   * `running`, or immediately if it is already idle with no queued work. A
-   * non-owner's quiescence-observation hook: a consumer that does NOT own the
-   * agent's lifecycle awaits this to proceed only after queued/running work has
-   * fully stopped, rather than returning while the driver is still streaming or
-   * about to start a queued turn — without itself tearing the agent down. (A
-   * lifecycle OWNER does not need it: `AgentHandle.dispose()` already awaits the
-   * loop-exit promise directly as part of stopping and unregistering. So this is
-   * for a non-owning observer — e.g. a test awaiting a turn to settle, or a
-   * monitor — that wants the settle signal but must not dispose the agent.)
-   *
-   * "Quiescence", not merely "status changed": a disposed agent emits
-   * `agent/status('disposed')` from inside its disposer, BEFORE the driver loop
-   * has unwound — so `whenIdle()` resolving on `disposed` must wait for the loop
-   * to actually exit (the implementation chains the loop-exit promise), not just
-   * observe the status flip. A mid-step disposal that never reaches `idle` still
-   * unblocks the await this way.
-   */
+  /** Resolve at idle quiescence; disposal waits for driver exit rather than only the status transition. */
   whenIdle(): Promise<void>
 
-  // Subagent delegation is realized on top of this interface by the
-  // `@deepseek-ai/dsh-subagent` seam, not by a method here: a backend creates
-  // the child through `ctx.agents.create` (fork seeds the child Session with a
-  // balanced prefix of the parent's log via `CreateAgentOptions.seed`; spawn
-  // starts fresh) and drives it as an ordinary Agent handle, so steer() and
-  // event subscription work uniformly. See docs/core-data-structures/subagent.md.
 }
 
 declare module 'cordis' {
   interface Events {
     // ---- lifecycle (emit) ----
     /**
-     * An agent's fully composed scoped world was published in the
-     * {@link AgentRegistry}. Its session is already live in the session store.
-     * Setup is composition-only by contract; the subsequent
-     * `agent/session-start` boundary is the first supported place to inject or
-     * queue startup work. A synchronous listener throw
-     * vetoes publication and rollback emits the matching disposal edges;
-     * returned-promise rejection is observed and logged but cannot
-     * retroactively veto this synchronous boundary. A synchronous listener
-     * that requests the advanced registry detach does not remove the entry
-     * immediately: removal and the paired `agent/disposed` edge wait until the
-     * creation dispatch unwinds, so no later creation listener observes a
-     * disposal that preceded its own creation callback.
+     * A fully configured agent and live session were published. Setup is
+     * composition-only; `agent/session-start` is the first startup-driving seam.
+     * Synchronous listener failure vetoes publication, while returned-promise
+     * rejection is reported. Detach requested during dispatch waits until every
+     * creation listener has observed the stable entry.
      * @param agent - the newly registered agent with its live session and completed setup.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode emit
      */
     'agent/created'(this: Scoped<Agent>, agent: Agent): void
     /**
-     * An agent was removed from the registry. The concrete AgentLoop lifecycle
-     * emits this only after its driver and any in-flight turn reach quiescence;
-     * a custom agent registered through the public registry owns its own driver
-     * contract, which the registry cannot infer. Ordered teardown may still be
-     * detaching the session and unwinding scoped registrations when this runs.
+     * An agent left the registry; AgentLoop emits this after driver quiescence
+     * but before session detachment and scoped-registration unwind. Custom
+     * registry users own their driver-ordering contract.
      * @param agent - the exact agent removed from the registry.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode emit
      */
     'agent/disposed'(this: Scoped<Agent>, agent: Agent): void
     /**
-     * Agent status changed (`idle` ⇄ `running`, or → `disposed`). Drive
-     * lifecycle off this transition, never off a status you just requested —
-     * `send()` does not flip status to `running` before it returns.
+     * Agent status changed (`idle` ⇄ `running`, or → `disposed`). `send()` does
+     * not enter `running` synchronously; drive lifecycle from this event.
      * @param agent - the agent whose status flipped.
      * @param status - the status just entered (the transition's destination).
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode emit
      */
     'agent/status'(this: Scoped<Agent>, agent: Agent, status: AgentStatus): void
     /**
-     * A message entered the agent's inbox (queued or steering). Content and the
-     * resolved source are the detached, deeply-frozen values retained by the
-     * inbox. `source` has defaults applied and is not the caller's raw options.
+     * Detached, frozen content entered the agent's inbox. Source defaults have
+     * already been applied, so these are the exact values retained for the log.
      * @param agent - the agent whose inbox received the message.
      * @param content - the accepted content blocks retained by the inbox.
      * @param info - the accepted source plus whether it entered as steering.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode emit
      */
     'agent/queued'(this: Scoped<Agent>, agent: Agent, content: ContentBlock[], info: { source: MessageSource; steering: boolean }): void
 
     // ---- session lifecycle (emit) ----
     /**
-     * The agent's session lifecycle began, fired once before its first turn.
-     * `source` says why ({@link SessionStartSource}: fresh startup, a resumed
-     * persisted session, …). A pure NOTIFICATION (emit, not waterfall): a
-     * listener cannot veto by returning a decision or throwing. A listener that
-     * wants to seed context does so via `agent.inject()` (a `context/message` the
-     * first request sees). A lifecycle owner can still dispose its structural
-     * ownership edge during this notification; publication rechecks liveness and
-     * then aborts before the driver starts.
+     * The session lifecycle began, once before the first turn. Use
+     * `agent.inject()` to seed model-facing context. This is a notification, not
+     * a veto; disposal requested by a lifecycle owner is rechecked before the
+     * driver starts.
      * @param agent - the agent whose session lifecycle began.
      * @param source - why the session started (fresh startup, resume, …).
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode emit
      */
     'agent/session-start'(this: Scoped<Agent>, agent: Agent, source: SessionStartSource): void
 
-    // Turn and step boundaries are NOT mirrored as agent/* emits: a consumer
-    // that needs them reads the durable `turn/start`/`turn/end`/`step/start`/
-    // `step/end` session events off the `session/event` feed (the session log is
-    // the live transcript feed). See the module doc's three-domain rule and the
-    // "remove agent boundary mirror events" RFC.
+    // Turn and step boundaries are durable session events, not agent events.
 
     // ---- step/request extension seams (serial + waterfall) ----
     /**
-     * Awaited pre-step surface-mutation checkpoint, fired once per step AFTER
-     * `turn/start` (and after the prior step closed) but BEFORE this step's
-     * `step/start` — so anything a listener appends lands OUTSIDE the step,
-     * between `turn/start`/`step/end` and the upcoming `step/start`. `step` is
-     * the number of the step about to start. The loop awaits
-     * `ctx.serial('agent/pre-step', …)` after assembling the system prompt, then
-     * opens the step and derives the request history ONCE from whatever the
-     * surface now holds. This is where compaction belongs: it mutates the session
-     * surface in place (shadowing an older range with a summary node) with its
-     * log-only `compact/*` records cleanly outside any step, and the single
-     * subsequent derive reflects the mutation — so there is no double-derive and
-     * no listener can see (or be expected to act on) an assembled `messages`
-     * array that does not exist yet.
-     *
-     * Serial (awaited in registration order), not a waterfall: a listener
-     * mutates the surface as a side effect; there is nothing to transform, but
-     * the loop must wait for the mutation to complete before opening the step
-     * and deriving. Cordis `serial` bails early if a listener returns a bail
-     * value; this event is typed and documented as `void`, so listeners must not
-     * return a semantic veto value. `fullSystemPrompt` is the assembled prompt a
-     * listener needs to measure pressure (the system prompt counts toward the
-     * budget), and `sessionPrefix` is the instance's composed
-     * {@link agent/session-prefix} product for the same reason — every request
-     * carries it in front of the derived history, and it is composed BEFORE
-     * this seam fires precisely so a pressure gate counts the prefix the
-     * request will actually send (never a stale logged one). `signal` cancels
-     * any in-flight work a listener starts (e.g. a
-     * summarization model call).
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
-     * @param agent - the agent about to open the step.
-     * @param turn - the already-open turn this step belongs to.
-     * @param step - the number of the step about to start.
-     * @param fullSystemPrompt - the assembled prompt, for measuring token pressure.
-     * @param sessionPrefix - the instance's frozen session prefix, for the same measurement.
-     * @param signal - aborts in-flight listener work when the turn is torn down.
+     * Awaited serial checkpoint for session-surface mutation after prompt
+     * assembly and before `step/start`; appends land outside the pending step.
+     * The loop derives history once afterward, so compaction records and
+     * replacements are included without rewriting an assembled request. The
+     * prompt and prefix are the exact pressure inputs for that request, and
+     * `signal` cancels listener work.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
+     * @param agent - the agent opening the step.
+     * @param turn - the open turn number.
+     * @param step - the pending step number.
+     * @param fullSystemPrompt - the assembled prompt.
+     * @param sessionPrefix - the frozen request prefix.
+     * @param signal - the turn abort signal.
      * @mode serial
      */
-    // TODO: `fullSystemPrompt`/`sessionPrefix` are a smell on a generic
-    // per-step seam — compaction
-    // is their only consumer, so a wide event carries payloads just one listener
-    // reads. Revisit if no second consumer appears: e.g. hand listeners a lazy
-    // prompt provider, or move token-pressure measurement behind a
-    // compaction-specific seam instead of the shared pre-step checkpoint.
+    // TODO: Move prompt-pressure inputs behind a compaction-specific seam if no second consumer appears.
     'agent/pre-step'(this: Scoped<Agent>, agent: Agent, turn: number, step: number, fullSystemPrompt: string, sessionPrefix: readonly Message[], signal: AbortSignal): Promise<void> | void
     /**
-     * Waterfall: decide what happens to ONE drained queued message before it
-     * becomes a `user/message` — allow (optionally rewriting the prompt bytes or
-     * attaching `additionalContext`) or block it. Fires inside the already-open
-     * turn, per drained message. Maps onto Claude Code's `UserPromptSubmit` hook.
-     * Call `next()` to delegate to the default (allow unchanged), or return a
-     * {@link PromptDecision} without calling `next()` to short-circuit.
+     * Allow, rewrite, or block one drained prompt before it becomes a user
+     * message. Call `next()` for the unchanged default.
      * @param agent - the agent draining its inbox.
      * @param content - the drained message's blocks, as queued.
      * @param source - the message's resolved source.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode waterfall
      */
     'agent/prompt-submit'(this: Scoped<Agent>, agent: Agent, content: ContentBlock[], source: MessageSource, next: () => Promise<PromptDecision>): Promise<PromptDecision>
     /**
-     * Waterfall: shape the step's call configuration — model switching,
-     * sampling overrides — by returning a replacement {@link LlmCallConfig}
-     * (the frozen seed is the config the loop would otherwise use). Config is
-     * ALL a listener shapes here: every request is a pure function of the
-     * session log (the reconstructability RFC), so model-visible content
-     * flows through the log channels — `inject()`, steering, prompt-submit
-     * `additionalContext`, prompt sections via `system-prompt/assemble`, or
-     * the header-logged session prefix via {@link agent/session-prefix}
-     * — never through request mutation, and the loop records whatever config
-     * the request actually uses as a `request/header*` event before dispatch.
-     * The step's messages are already snapshotted when this fires (the
-     * `step/start` boundary): an `inject()` from a listener here lands in the
-     * log but joins the NEXT request. For surface mutation that must precede
-     * the snapshot (compaction), use {@link agent/pre-step}. Call `next()` to
-     * delegate, or return an {@link LlmCallConfig} without it to
-     * short-circuit.
+     * Replace the frozen call configuration. Model-visible content must use
+     * logged channels; this seam cannot mutate messages. Injection here joins
+     * the next request because the current step boundary is already fixed.
      * @param agent - the agent making the model call.
      * @param turn - the open turn number.
      * @param step - the step whose request this is.
      * @param config - the config the loop would use (frozen); return a replacement to switch.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode waterfall
      */
     'agent/request'(this: Scoped<Agent>, agent: Agent, turn: number, step: number, config: LlmCallConfig, next: () => Promise<LlmCallConfig>): Promise<LlmCallConfig>
     /**
-     * Waterfall: compose the SESSION PREFIX — request-only messages placed in
-     * front of the ENTIRE derived history (directly after the provider's
-     * system slot) on every request this loop instance sends. Fired ONCE per
-     * loop instance, lazily before its first step's {@link agent/pre-step}
-     * seam — BEFORE the pre-step so a token-pressure gate (compaction) counts
-     * the prefix this instance will actually send, never a previous
-     * instance's logged one. The composed
-     * result is deep-frozen, recorded as `EpochHeader.messagePrefix` on the
-     * instance's anchoring `'initial'`/`'resume'` header snapshot, and reused
-     * verbatim for every subsequent request — never recomputed mid-session,
-     * so the provider prefix cache holds by construction (a process restart
-     * or `ctx.agents.resume()` is a new instance: it recomposes, and any
-     * drift lands attributably on the `'resume'` snapshot). Composition runs
-     * outside the step, before the boundary snapshot: a composing listener's
-     * session append joins the CURRENT request's derived history. A
-     * composition interrupted by a cancel/dispose landing inside the
-     * waterfall is discarded — never cached, logged, or sent — and the next
-     * turn recomposes under a live signal, so an abort-aware listener's
-     * degraded fallback cannot leak into later requests.
-     *
-     * This is the home for session-stable openers the model must always see
-     * but that must NOT become durable history — a skills catalog, an
-     * AGENTS.md digest, a workspace baseline: `Session.deriveMessages()`
-     * never returns the prefix, and the header events are its only durable
-     * record, so the request stays reconstructable from the log. Content
-     * that CHANGES mid-session belongs in the append-only history channels
-     * instead — `agent.inject()`, a `tools/post-execute` decision's
-     * `additionalContext`, prompt-submit `additionalContext` — each a
-     * durable `context/message` paid once and prefix-cached thereafter.
-     *
-     * The seed is a frozen empty list; a contributing listener returns a NEW
-     * array — never an in-place push. The canonical contribution is a
-     * PREPEND, `[mine, ...await next()]`: the waterfall unwinds
-     * innermost-first (the LAST-registered listener's `next()` resolves
-     * first), so prepending yields registration order on the wire, and every
-     * plugin using it composes deterministically. The append form
-     * `[...await next(), mine]` is legal but places a contribution AFTER
-     * every later-registered plugin's — reverse registration order when all
-     * contributors append. Call `next()` to
-     * delegate, or return a list without it to short-circuit.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Compose request-only messages placed before derived history. The frozen
+     * result is computed once per loop instance, logged on its anchoring request
+     * header, and reused so the provider prefix remains stable. Interrupted
+     * composition is discarded. Composition precedes the first `agent/pre-step`
+     * and request boundary, so listener appends join the current request and
+     * pressure accounting sees the composed prefix. Changing context belongs in
+     * history; contributors should prepend to `await next()` to preserve registration order.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @param agent - the agent whose session prefix is being composed.
-     * @param prefix - the frozen empty seed; return an extended replacement to contribute.
-     * @param signal - aborts in-flight listener work (e.g. a discovery scan) when the step is torn down.
+     * @param prefix - the frozen seed; return an extended replacement.
+     * @param signal - aborts composition when the step is torn down.
      * @mode waterfall
      */
     'agent/session-prefix'(this: Scoped<Agent>, agent: Agent, prefix: Message[], signal: AbortSignal, next: () => Promise<Message[]>): Promise<Message[]>
@@ -542,47 +244,27 @@ declare module 'cordis' {
      * @param turn - the open turn number.
      * @param step - the step that produced the message.
      * @param message - the assistant message as assembled from the stream.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode waterfall
      */
     'agent/step-result'(this: Scoped<Agent>, agent: Agent, turn: number, step: number, message: Message, next: () => Promise<Message>): Promise<Message>
     /**
-     * Waterfall: override the turn-continuation decision via a typed
-     * {@link ContinuationDecision}. The loop's `defaultDecision` is `continue`
-     * when the step had tool calls or steering was injected, else `stop`.
-     * Listeners force-continue (`/goal`, `/loop` — optionally attaching a
-     * `reason` recorded as next-step steering) or force-stop (budget guards).
-     * Call `next()` to delegate to the default, or return a decision to override.
+     * Override whether the turn continues. The default continues after tool
+     * calls or steering and stops otherwise; a continue reason becomes steering.
      * @param agent - the agent deciding whether to run another step.
      * @param turn - the turn being continued or stopped.
      * @param defaultDecision - what the loop would do absent an override.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode waterfall
      */
     'agent/turn-continuation'(this: Scoped<Agent>, agent: Agent, turn: number, defaultDecision: ContinuationDecision, next: () => Promise<ContinuationDecision>): Promise<ContinuationDecision>
     /**
-     * Serial terminal-stop checkpoint after the ordinary
-     * `agent/turn-continuation` waterfall, any `continue.reason`, and the
-     * pending-steering continuation override have been folded. A listener
-     * returns `{ action: 'stop' }` to make this turn terminal, or `undefined`
-     * to abstain. Terminal stop is monotonic: listener order and steering
-     * cannot resume the turn, and pending steering is discarded rather than
-     * becoming another step or turn.
+     * Monotonic terminal-stop checkpoint after continuation and steering are
+     * folded; a stop remains authoritative through turn close and flush:
+     * steering queued in that window is discarded, while ordinary sends survive.
      * @param agent - the agent whose composed continuation outcome may be stopped.
      * @param turn - the turn at its terminal-stop checkpoint.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode serial
      */
     'agent/turn-stop'(this: Scoped<Agent>, agent: Agent, turn: number): ContinuationStop | undefined
@@ -595,11 +277,7 @@ declare module 'cordis' {
      * @param turn - the turn in which the failure surfaced.
      * @param step - the step at which the failure surfaced.
      * @param error - the failure, verbatim.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): a listener registered
-     * through `agent.ctx` fires only for that agent's dispatches; a listener on a
-     * plain plugin context fires for every agent. The dispatch `this` is the
-     * scope carrier (`Scoped<Agent>`), built by the emitting side via
-     * `scopeTarget`/`agentEvents`.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent.
      * @mode emit
      */
     'agent/error'(this: Scoped<Agent>, agent: Agent, turn: number, step: number, error: Error): void

packages/core/agent/tests/gen-cordis-catalog.spec.ts

@@ -1,16 +1,5 @@
 /**
  * Negative-path tests for the cordis catalog generator (`scripts/gen-cordis-catalog.ts`).
- *
- * The generated catalog is frozen by a regenerate-and-diff freshness gate, so
- * the freshness half is exercised by `pnpm run verify-cordis-catalog` in CI.
- * What a freshness diff CANNOT prove is that the generator REJECTS malformed
- * source the way it promises to — a missing `@mode` tag, a tag that
- * contradicts the signature shape, or a JSDoc-completeness violation (missing
- * prose, an undocumented parameter, a stale `@param`, a missing `@returns`, an
- * unannotated return type). These tests drive `collectEvents()` /
- * `collectServices()` against synthetic fixture packages to prove each guard
- * fires (and that well-formed declarations pass), mirroring the drift-guard
- * negative tests for verify-type-equiv.
  */
 
 import { mkdtempSync, mkdirSync, rmSync, writeFileSync } from 'node:fs'

packages/core/agent/tests/verify-export-jsdoc.spec.ts

@@ -1,15 +1,5 @@
 /**
- * Negative-path tests for the export-surface JSDoc gate
- * (`scripts/verify-export-jsdoc.ts`).
- *
- * The gate's positive half runs against the real tree in CI (`pnpm run
- * verify-export-jsdoc`, part of doc-sync). What that run cannot prove is that
- * the walk REJECTS an undocumented surface the way it promises to — and that
- * every deliberate exemption (heritage members, plugin-protocol slots,
- * constructors, overload implementations, augmentation bodies, re-exports)
- * actually holds. These tests drive `collectExportJsdocViolations()` against
- * synthetic fixture packages, mirroring the gen-cordis-catalog negative
- * tests.
+ * Negative-path tests for the export-surface JSDoc gate (`scripts/verify-export-jsdoc.ts`).
  */
 
 import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from 'node:fs'
@@ -160,7 +150,7 @@ describe('verify-export-jsdoc export forms', () => {
     ))).toEqual([expect.stringMatching(/exported function 'f' .* has no JSDoc\./)])
   })
 
-  it('does not treat a never-exported sibling declarator as surface (review round 2)', () => {
+  it('does not treat a never-exported sibling declarator as surface', () => {
     // `export { publicValue }` resolves to the whole variable statement; only
     // the named declarator is surface — the gate must not demand JSDoc for
     // the private sibling sharing the statement.
@@ -169,7 +159,7 @@ describe('verify-export-jsdoc export forms', () => {
     ))).toEqual([])
   })
 
-  it('unions declarators across multiple export lists over one statement (review round 2)', () => {
+  it('unions declarators across multiple export lists over one statement', () => {
     // Two lists each name one declarator of the same undocumented statement:
     // both are surface (deduplicating on first resolution would drop `b`),
     // while the never-exported `c` stays out.
@@ -182,7 +172,7 @@ describe('verify-export-jsdoc export forms', () => {
     ])
   })
 
-  it('scopes a default-export identifier to its own declarator (review round 2)', () => {
+  it('scopes a default-export identifier to its own declarator', () => {
     // `export default` of an identifier reaches the statement through the
     // same name lookup as an export list; the sibling stays private.
     expect(collectExportJsdocViolations(make(
@@ -325,7 +315,7 @@ export namespace Loose {
   })
 })
 
-describe('verify-export-jsdoc fail-closed forms (review round 1)', () => {
+describe('verify-export-jsdoc fail-closed forms', () => {
   it('checks the function contract on a non-identifier default export', () => {
     expect(collectExportJsdocViolations(make(
       '/** Doubles. */\nexport default (x: number): number => x * 2\n',
@@ -418,7 +408,7 @@ describe('verify-export-jsdoc fail-closed forms (review round 1)', () => {
   })
 })
 
-describe('verify-export-jsdoc heritage refinement (review round 1)', () => {
+describe('verify-export-jsdoc heritage refinement', () => {
   it('requires @param for parameters the base member never names', () => {
     const violations = collectExportJsdocViolations(make(`
 /** Seam. */

packages/core/scope/README.md

@@ -1,6 +1,6 @@
 # dsh-scope
 
-Scoped-context registration primitive. `createScope(ctx, key)` mints a Cordis context that TAGS everything registered through it with an opaque `ScopeKey` and OWNS those registrations' lifetime (one backing fiber drives both facts); `scopeOf(ctx)` reads the tag; `scopeTarget(base, key)` builds the dispatch carrier that makes an event scope-filtered — listeners registered through a scoped context fire only for their key's subject, while plain plugin listeners keep firing for every subject. The agent loop is the one scope minter today (one scope per live agent, key = the `Agent` object — the `Agent.ctx` contract in `dsh-agent`), but the mechanism is key-agnostic so packages below the agent layer (`dsh-session`, `dsh-system-prompt`) depend on it without a dependency cycle.
+Scoped registration primitive. `createScope(ctx, key)` creates a tagged Cordis context whose backing fiber owns every registration made through it. `scopeOf(ctx)` reads the tag, and `scopeTarget(base, key)` routes scoped events to listeners with the same key while leaving unscoped listeners global. The agent loop creates one scope per live agent, but the mechanism is key-agnostic so lower-level packages can use it without depending on agents.
 
 ## Public API
 
@@ -15,7 +15,7 @@ Scoped-context registration primitive. `createScope(ctx, key)` mints a Cordis co
 
 ## Design contract
 
-Ownership and visibility derive from ONE fact — which context a registration went through. An explicit `{ scope }` registration parameter could express "visible to X, disposed with Y", which is almost always a bug; the scoped context makes it unrepresentable. This is trusted registration and listener routing, not sandboxing or an authority hierarchy: a same-process plugin is not confined, and a child scope need not be a subset of its parent's view. Rationale, alternatives, and the security non-goal: [the agent-scope RFC](../../../docs/rfc/implemented/architecture/2026-07-08-agent-scope-contexts.md#security-and-authority-are-explicit-non-goals).
+The registration context determines both visibility and ownership, preventing a registration from being visible in one scope but disposed with another. Scopes route trusted same-process plugins; they are not sandboxes or authority boundaries. See the [agent-scope RFC](../../../docs/rfc/implemented/architecture/2026-07-08-agent-scope-contexts.md#security-and-authority-are-explicit-non-goals) for rationale and security non-goals.
 
 Handing out a scoped context hands out the minting plugin's service-resolution surface (resolution walks the minting fiber's dependency chain, not the holder's) — mint it from the plugin whose dependencies the scoped registrations need to resolve.
 

packages/core/scope/src/index.ts

@@ -73,15 +73,11 @@ export function scopeOf(ctx: Context): ScopeKey | undefined {
 }
 
 /**
- * Build the routing receiver for a scope-filtered event. Untagged listeners
- * remain global; tagged listeners run only when their key matches. A base
- * Cordis filter is composed before the scope predicate.
- *
- * The receiver is deliberately opaque: listener code obtains the real subject
- * from event arguments, never from `this`.
+ * Build an opaque receiver that preserves the base filter, admits untagged
+ * listeners globally, and admits tagged listeners only for a matching key.
  * @param base - subject or service whose existing Cordis filter is preserved.
  * @param key - routed scope identity, or `undefined` for an unscoped subject.
- * @returns an opaque dispatch carrier.
+ * @returns a carrier whose subject remains available only through event arguments.
  */
 export function scopeTarget<T extends object>(base: T, key: ScopeKey | undefined): Scoped<T> {
   const baseFilter = (base as { [CordisContext.filter]?: (ctx: Context) => boolean })[CordisContext.filter]

packages/core/session/README.md

@@ -8,35 +8,35 @@ Creates and holds event-sourced `Session` instances. Persistence is intentionall
 
 ### Public API
 
-- `ctx.sessions.create(id?: SessionId, options?: { seed?: readonly SessionEvent[]; meta?: { cwd?: string; parentSession?: SessionId; createdAt?: number; seedLength?: number } }): Session` — Create a session. The persistence/replay seed and resulting header are validated, detached, and deep-frozen at this durable boundary. The store fills `version`/`id` and defaults `createdAt` to now; a persisted reconstruction supplies the original `createdAt` and `seedLength`. Disposed with the calling fiber.
-- `ctx.sessions.flush(session: Session): Promise<void>` Dispatch the awaited `session/flush` durability checkpoint with the carrier captured at enter — THE flush entry point (the loop's turn-end checkpoint and idle injection call it; never dispatch a raw `ctx.parallel`). Every captured listener starts, the call waits for all of them to settle, and a failure rejects only after the other listeners finish. Rejects a prepared, detached, or stale same-id object instead of inventing a subject-less carrier.
+- `ctx.sessions.create(id?, { seed?, meta? }?)` validates and detaches durable seed/header data, fills the version and id, defaults `createdAt` to now, publishes the session, and binds it to the calling fiber. Persisted reconstruction supplies its original `createdAt` and `seedLength`.
+- `ctx.sessions.flush(session)` dispatches the awaited parallel durability checkpoint through the session's captured scope. Every listener starts and the call waits for all to settle before reporting failure; unpublished, detached, and stale objects reject.
 - `ctx.sessions.fork(source, boundary?, childSessionId?): Session` — Resolve a live session object or id, select a seed through the inclusive `boundary` event seq (default: current last event), require that boundary to be `turn/end`, and create a live child session with lineage metadata.
 - `ctx.sessions.get(id: SessionId): Session | undefined`
 - `ctx.sessions.list(): Session[]`
 
 #### Advanced: ordered-teardown lifecycle primitives
 
-`create()` covers the common case (the session is owned by the calling fiber). When a session must be torn down **in order with another resource** — so a final flush is captured before the store attachment and publication hooks are removed — `create()`'s self-contained effect is wrong, because a fiber unload disposes sibling effects *concurrently*. For that, split the lifecycle and fold it into the owner's single effect:
+Use the split lifecycle only when teardown must be ordered with another resource:
 
-- `ctx.sessions.prepare(id?, options?): Session` — validate durable seed/header data and construct the `Session` WITHOUT entering it into the store. Same options as `create`.
-- `ctx.sessions.enter(session): () => void` — perform the authoritative ID collision check, install append publication state, and insert the exact session without announcing it. Returns an idempotent detach bound to the captured entry object, so a stale disposer cannot remove a later same-ID replacement. Concurrent same-ID preparation is allowed; only one final entry succeeds.
-- `ctx.sessions.announce(session): void` — begin the one allowed `session/created` announcement for an entered session; repeat and reentrant calls reject before dispatch. A detach requested synchronously by a creation listener is deferred until that dispatch unwinds, so another creation listener cannot observe `session/disposed` before its own `session/created` callback. Detach emits `session/disposed` exactly once, including rollback after a partially delivered creation notification; a never-announced entry emits neither edge.
+- `prepare(id?, options?)` validates and constructs without publication.
+- `enter(session)` performs the collision check, publishes without announcing, and returns an entry-bound idempotent detach. Concurrent same-id preparations are allowed, but only one entry succeeds; a stale detach cannot remove its replacement.
+- `announce(session)` emits the single creation edge and rejects repeat or reentrant announcements. Detach during that dispatch is deferred and later emits the paired disposal edge; an unannounced entry emits neither lifecycle edge.
 
-`dsh-agent-loop` is the canonical consumer: after unpublished agent setup it enters both session and agent before announcing either, then nests loop stop, agent removal, session detach, and scope unwind in one ordered lifecycle. The final flush therefore settles before this package detaches the session, whether teardown starts from an `AgentHandle` or owner-fiber unload.
+`dsh-agent-loop` uses this split so final loop flush precedes session detach; see the [ownership RFC](../../../docs/rfc/implemented/architecture/2026-06-18-agent-lifecycle-and-ownership-seams.md).
 
 ### Live service events
 
-The store pairs announced creation with disposal, publishes each append, and provides an awaited durability checkpoint. Before the log push it resolves the scoped `session/event` callback list. The push is the commit point; callback throws or returned-promise rejections are logged and contained per observer. A committed append therefore returns normally, later observers still run, and detach waits until publication unwinds. Exact `session/*` signatures, modes, and scope-carrier behavior live in the generated [Cordis event catalog](../../../docs/cordis-catalog/events.md); the append-only payload vocabulary is separately generated into the [persistence catalog](../../../docs/persistence-catalog.md).
+The store pairs announced creation with disposal, publishes post-commit append notifications with per-listener containment, and provides an awaited durability checkpoint. Exact signatures and scope behavior live in the generated [event catalog](../../../docs/cordis-catalog/events.md); payloads live in the [persistence catalog](../../../docs/persistence-catalog.md).
 
 ### Class: `Session`
 
 Plain class (not a Cordis Service). Create via `ctx.sessions.create()`.
 
-- `session.append(type, data, opts?): SessionEvent` — synchronous, never blocks on I/O. At this durable boundary, data and surface metadata are lossless-JSON snapshotted and deep-frozen. For an attached session, a reentrant append during dispatch/observer publication rejects, and detach waits for that publication to unwind. Callbacks resolve before the log push; the push is the commit point, after which each observer failure is contained independently. Runtime surface validation covers widened unions and raw seed/load logs.
-- `session.deriveMessages(): Message[]` — the LLM message history, CACHED: each surface node is projected exactly once, when first seen (O(new nodes) per call; a surface rewrite rebuilds via `surface.replaceGeneration`). Returns a fresh array per call over shared, deep-frozen `Message` objects. Each projection reuses the already deep-frozen content in its durable log event, so no second deep clone is needed and a consumer still cannot mutate logged data. The surface is the single source of derived history — there is no raw-log fallback.
-- `session.deriveEventMessage(event): Message | null` — the per-event projection `deriveMessages()` folds: a fresh message wrapper that reuses the event's already frozen content, or `null` when the event produces none (a non-surface event, or an empty-content `assistant/message` hosting only usage). External reconstructors and the dev invariant fold the same function over a log prefix's surface, so no two paths can disagree about what a request's messages were (the reconstructability RFC).
-- `session.surface: SurfaceManager` — the derived surface, lazily built from `surfaceOp` markers in the log. Processes only new events (delta) on each access — the log is append-only, so prior events never change. `surface.replaceGeneration` is the rewrite signal, bumped by every folded `replace`, so an incremental consumer knows when to rebuild.
-- `session.events` — a cached, frozen array snapshot over deep-frozen events. Repeated reads without an append return the same array; an append invalidates the cache and the next read returns a new snapshot, while earlier snapshots stay unchanged. Neither a cast nor a retained reference can push into the live log or rewrite an accepted event.
+- `session.append(type, data, opts?)` snapshots and freezes durable data and surface metadata, commits synchronously, then notifies observers with independent failure containment. Reentrant attached-session appends reject, and runtime checks cover widened unions and loaded logs.
+- `session.deriveMessages()` incrementally projects each new surface node once and returns a fresh array over shared frozen messages. A surface rewrite rebuilds the projection; there is no raw-log fallback.
+- `session.deriveEventMessage(event)` is the canonical per-event projection used by reconstruction and invariants.
+- `session.surface` lazily folds only new `surfaceOp` markers; `replaceGeneration` changes on every rewrite.
+- `session.events` is a cached frozen snapshot invalidated by append; accepted events remain deeply frozen.
 - `session.seq`, `session.id` — current sequence and readonly typed identity.
 - `session.header: SessionHeader` — detached, deep-frozen creation metadata (`version`, `id`, `createdAt`, optional `cwd`/`parentSession`/`seedLength`). Construction validates the durable record and requires its id to match `session.id`.
 
@@ -54,7 +54,7 @@ Durable values need one accepted representation, not a check followed by a secon
 
 ### Request-header reconstruction (`request-header.ts`)
 
-The `request/header` (full `EpochHeader` snapshot with a `RequestHeaderReason`) and `request/header-delta` (system line-trim / name-keyed tools delta / whole config / whole session prefix) events make the request envelope logged session state, so every conversation request is a pure function of the log. The pure trio reconstructs it: `foldRequestHeader(events)` folds a log (or any prefix) into the header in force; `diffHeader(prev, next)` encodes a change (undefined when equal); `applyHeaderDelta(prev, delta)` replays one. Writer contract: every logged delta is round-trip-verified (`apply(prev, delta)` deep-equals the new header) with a `'fallback'` snapshot when the encoding cannot express the change (a pure tool reordering), so folding never needs error recovery on a well-formed log. `canonicalHeader` pins the one representation of absence (empty system/tools/messagePrefix ≡ absent fields; a delta's EMPTY prefix array encodes the transition back to absence). `EpochHeader.messagePrefix` is the durable record of the `agent/session-prefix` waterfall's product — composed once per loop instance, the request is `messagePrefix + derived history`, and `deriveMessages()` never returns it.
+`request/header` and `request/header-delta` make the non-history request envelope reconstructable from the log. `foldRequestHeader()` reconstructs the active header, `diffHeader()` encodes changes, and `applyHeaderDelta()` replays them; unsupported deltas fall back to a full snapshot. `messagePrefix` remains separate from derived history. See the [reconstructable-requests RFC](../../../docs/rfc/implemented/architecture/2026-07-05-reconstructable-requests.md).
 
 ### Session event vocabulary (`types.ts`)
 
@@ -76,7 +76,7 @@ Every `SessionEvent` carries two optional top-level fields (structural metadata)
 ### Extension points
 
 - Persistence plugins: subscribe to `session/event` (write-behind) and drain on `session/flush` (awaited) and fiber dispose. A durable backend reads the log and reloads it into a live session; the metadata seam (`SessionHeader`, `session.header`) is what such a backend stores beside the log.
-- Replay/fork: `ctx.sessions.create(id, { seed })` seeds a new session with an existing event log. The surface rebuilds deterministically from `surfaceOp` markers in the seeded events. The constructor reads each seed entry once and uses the same one-pass lossless-JSON snapshot and exact surface-metadata shape checks as `append`, then enforces contiguous seqs and deep-freezes every accepted record; a stateful caller, exotic nested value, marker-less or malformed surface event, metadata on a non-surface event, or retained seed reference therefore cannot silently change the reconstructed history. Broader turn-enclosure checks stay in `dsh-invariants` and persistence repair. Ordinary live-session forks use `ctx.sessions.fork(source, boundary?, childSessionId?)`, where `boundary` is the inclusive source event seq to fork through.
+- Replay/fork: `create(id, { seed })` validates and freezes a contiguous log and rebuilds its surface. `fork(source, boundary?, childSessionId?)` selects a completed-turn prefix and records lineage.
 - Compaction: the `dsh-compact-basic` plugin appends a `user/message` with `surfaceOp: { op: 'replace', start, end }` to shadow old surface nodes behind a summary checkpoint.
 
 ## Model Experience

packages/core/session/src/index.ts

@@ -34,67 +34,41 @@ declare module 'cordis' {
 
   interface Events {
     /**
-     * A session was created in the store. A synchronous listener throw vetoes
-     * publication and rollback emits the matching `session/disposed` edge;
-     * returned-promise rejection is observed and logged but cannot retroactively
-     * veto this synchronous boundary. A synchronous listener that requests the
-     * advanced detach does not remove the entry immediately: removal and the
-     * paired `session/disposed` edge wait until the creation dispatch unwinds.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): the carrier is the
-     * session's owner scope, captured when the session was ENTERED (an agent's
-     * session is entered through `agent.ctx`, so its events dispatch in that
-     * agent's scope; a bare `sessions.create()` from a plain plugin dispatches
-     * subject-less). A listener registered through `agent.ctx` hears only that
-     * agent's sessions; a plain plugin listener hears every session.
+     * Creation announcement during session publication. A synchronous throw vetoes and rolls
+     * back with a paired disposal; detach requested during dispatch is deferred.
+     * A returned-promise rejection is logged but cannot retroactively veto this
+     * synchronous boundary.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners
+     * receive only sessions entered through that agent's context.
      * @param session - the session just entered and announced.
      * @mode emit
      */
     'session/created'(this: Scoped<Session>, session: Session): void
     /**
-     * A previously announced session left the store. Emitted exactly once on
-     * normal detach or publication rollback, and never for a prepared/entered
-     * session whose `session/created` announcement did not begin. Listener
-     * failures (including returned-promise rejections) are logged and contained
-     * per listener so teardown always reaches quiescence.
-     * Scope-filtered dispatch uses the same owner carrier captured at entry;
-     * agent-scoped listeners hear only their own session's teardown.
+     * Emitted once when an announced session leaves the store, including
+     * publication rollback, but never for an entry whose creation announcement
+     * did not begin. Listener failures are logged and contained.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`) reuses the owner scope.
      * @param session - the session that is no longer live in the store.
      * @mode emit
      */
     'session/disposed'(this: Scoped<Session>, session: Session): void
     /**
-     * An event was appended to a session log (sync, fire-and-forget). This is
-     * the per-append feed a UI or invariant plugin tails. The log push is the
-     * commit point; synchronous throws and returned-promise rejections from
-     * observers are logged and contained per listener, so they cannot make a
-     * committed append appear to fail or starve later listeners. The exact
-     * callback list and Cordis internal-dispatch checks resolve before the push;
-     * callbacks themselves run only after it.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): the carrier is the
-     * session's owner scope, captured when the session was ENTERED (an agent's
-     * session is entered through `agent.ctx`, so its events dispatch in that
-     * agent's scope; a bare `sessions.create()` from a plain plugin dispatches
-     * subject-less). A listener registered through `agent.ctx` hears only that
-     * agent's sessions; a plain plugin listener hears every session.
+     * Post-commit, fire-and-forget append feed. The listener snapshot resolves
+     * before the log push, but callbacks run after it; observer failures are
+     * logged and contained without making the committed append fail.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners
+     * receive only events from sessions entered through that agent's context.
      * @param session - the session whose log grew.
      * @param event - the appended event, exactly as recorded.
      * @mode emit
      */
     'session/event'(this: Scoped<Session>, session: Session, event: SessionEvent): void
     /**
-     * Awaited durability checkpoint. The agent loop awaits
-     * `ctx.sessions.flush(session)` at every turn end; persistence
-     * plugins (JSONL, SQLite) drain their write-behind buffers here and on
-     * fiber dispose. Awaited (parallel), not a waterfall: every listener runs
-     * and the caller waits for all of them, but none can veto. Dispatch it
-     * through {@link SessionStore.flush} — the store owns the carrier — never
-     * via a raw `ctx.parallel`.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): the carrier is the
-     * session's owner scope, captured when the session was ENTERED (an agent's
-     * session is entered through `agent.ctx`, so its events dispatch in that
-     * agent's scope; a bare `sessions.create()` from a plain plugin dispatches
-     * subject-less). A listener registered through `agent.ctx` hears only that
-     * agent's sessions; a plain plugin listener hears every session.
+     * Awaited parallel durability checkpoint: every listener runs and the
+     * caller awaits all of them, with no waterfall veto. Dispatch through
+     * {@link SessionStore.flush}. Scope-filtered dispatch
+     * (`@deepseek-ai/dsh-scope`) reuses the session's owner scope.
      * @param session - the session whose buffered events must reach durable storage.
      * @mode parallel
      */
@@ -103,13 +77,9 @@ declare module 'cordis' {
 }
 
 /**
- * Renders a `context/message` or `steering/message` event as a tagged
- * synthetic user-role message (the system-reminder pattern: zero adapter
- * burden, models distinguish it from real user prompts by the envelope).
- *
- * Live-adapter review has validated the tagged-envelope rendering against
- * current DeepSeek behavior; provider-specific mismatches belong in that
- * adapter, not in the canonical session vocabulary.
+ * Render injected context as tagged synthetic user-role content, keeping the
+ * canonical session vocabulary provider-neutral. Adapter-specific exceptions
+ * belong in the adapter.
  */
 function renderTagged(tag: string, content: ContentBlock[], source: MessageSource): ContentBlock[] {
   const open = `<${tag} source=${JSON.stringify(source.kind)}>`

packages/core/session/src/json.ts

@@ -1,17 +1,4 @@
-/**
- * Lossless-JSON validation and snapshot materialization for session data.
- *
- * The session event log is the durable source of truth (the event-sourcing / session-persistence RFCs): every
- * `event.data` must round-trip losslessly through JSON so any persistence
- * backend can store and reload it byte-identically. This invariant belongs to
- * the log itself — `Session.append` enforces it at the source, so a
- * non-serializable event never enters `session.events` and the live log can
- * never diverge from what a backend can persist. Other public boundaries use
- * {@link snapshotJsonValue} when they must validate and detach in one pass;
- * {@link isJsonValue} remains the non-copying structural predicate.
- *
- * @module @deepseek-ai/dsh-session/json
- */
+/** Lossless-JSON validation and detached snapshots for durable session data. @module @deepseek-ai/dsh-session/json */
 
 /**
  * A value that round-trips losslessly through JSON: `null`, a boolean, a finite
@@ -25,19 +12,10 @@
 export type JsonValue = null | boolean | number | string | JsonValue[] | { [key: string]: JsonValue }
 
 /**
- * Materialize one detached lossless-JSON snapshot in a SINGLE recursive pass.
- * Each array slot or own enumerable string-keyed object value is read exactly
- * once, validated, and copied immediately. This is intentionally not
- * `isJsonValue(value)` followed by `structuredClone(value)`: a stateful getter
- * could return plain JSON to the check and an exotic class instance to the
- * clone, whose prototype `structuredClone` would erase before a later check.
- *
- * Accepts the same scalar/object vocabulary as {@link isJsonValue}: arrays use
- * the ordinary `Array.prototype` (subclass instances are not plain JSON
- * containers), while null-prototype objects are accepted and normalized to
- * ordinary plain objects. Sparse arrays, cycles, negative zero, non-finite
- * numbers, unsupported scalar types, and exotic object or array shells return
- * `undefined`. A throwing getter is a caller failure and propagates unchanged.
+ * Validate and detach lossless JSON in one read per property, so a stateful
+ * getter cannot change between validation and copying. Accepts ordinary arrays,
+ * plain or null-prototype objects, and JSON scalars; rejects sparse, cyclic,
+ * exotic, negative-zero, and non-finite values. Getter throws propagate.
  *
  * @param value - the candidate value to validate and detach.
  * @returns the detached snapshot, or `undefined` when the value is not
@@ -104,28 +82,12 @@ export function snapshotJsonValue<T>(value: T): T | undefined {
 }
 
 /**
- * Whether `value` is losslessly JSON-serializable: only `null`, finite numbers
- * other than negative zero, booleans, strings, plain arrays, and plain objects
- * of such values. Rejects `BigInt`, function, symbol, `undefined`, `-0` (which
- * JSON rewrites to `0`), non-finite numbers (`NaN`/`Infinity`, which JSON turns
- * into `null`), and exotic objects (`Map`/`Set`/`Date`/class instances) —
- * anything `JSON.stringify` would drop, throw on, or convert lossily. Sparse
- * arrays are rejected too: a hole serializes to `null`, so `[1, , 3]` would not
- * round-trip. Detects circular references (which would throw) and reports them
- * as non-serializable rather than propagating the throw.
- *
- * Scope — this is a structural plain-data predicate, not an invocation of
- * `JSON.stringify`: only an object's OWN ENUMERABLE STRING-keyed properties are
- * inspected (`Object.values`). Symbol-keyed and non-enumerable properties are
- * omitted from the durable data surface. Custom `toJSON` behavior is not
- * executed; boundaries that persist a value first materialize a new plain-data
- * record with {@link snapshotJsonValue}. Getters are invoked during this check,
- * so callers that need a stable detached value use that one-pass materializer
- * instead of checking and then rereading a side-effecting record.
+ * Test the same lossless JSON boundary as {@link snapshotJsonValue} without
+ * detaching it. Only own enumerable string properties participate; `toJSON`
+ * is ignored and getters run, so persistence boundaries use the snapshotter.
  * @param value - the candidate event data to test.
- * @param seen - objects on the current descent path, for circular-reference
- *   detection; the recursion threads it — callers omit it.
- * @returns true when `value` survives a JSON round-trip losslessly.
+ * @param seen - current recursion path; callers omit it.
+ * @returns whether `value` survives JSON round-trip losslessly.
  */
 export function isJsonValue(value: unknown, seen: Set<object> = new Set()): boolean {
   if (value === null) return true

packages/core/session/src/repair.ts

@@ -1,37 +1,7 @@
 /**
- * Crash-recovery repair for an interrupted session log.
- *
- * A persistence backend flushes only at `turn/end`, so a crash can leave a
- * durable log whose final turn never closed: real, fully-written events sit
- * after the last `turn/end` with no closing boundary. A single turn can be huge
- * in a long-horizon task (many steps, large tool output), so those events MUST
- * be preserved — truncating the turn would silently destroy real work. Instead,
- * on reload the backend CLOSES the orphaned turn by appending the minimal
- * synthetic boundary events:
- *
- *   1. an error `tool/result` for every `tool-call` in the interrupted turn that
- *      never got its matching `tool/result` (so the rehydrated history is a
- *      VALID provider transcript — see below),
- *   2. a `step/end` if a step was still open, then
- *   3. a `turn/end` carrying the merge-extensible `{ kind: 'interrupted' }` reason.
- *
- * The marker records that the turn was cut short by a crash, not completed by
- * the model. See the session-persistence RFC.
- *
- * Why the synthetic tool results matter: `deriveMessages()` renders the
- * `tool-call` blocks inside a durable `assistant/message` but only emits a
- * matching tool-result when a `tool/result` EVENT exists. A crash between the
- * assistant message and its tool results (the loop runs the tools AFTER logging
- * the assistant message, so a process killed mid-tool leaves the calls without
- * results) would otherwise reload a history with a dangling assistant tool-call
- * — which every provider rejects as an invalid transcript on the next request.
- * Synthesizing an error result per orphaned call keeps resume safe.
- *
- * This module computes those synthetic closers from an event list; backends
- * return them inline from `load` (so the reconstructed session is balanced and
- * immediately usable) and persist them during that mutating load before any
- * later append continues the log.
- *
+ * Crash-recovery repair for an interrupted session log. It preserves a fully
+ * written final turn and supplies the missing tool, step, and turn boundaries
+ * needed to resume with a provider-valid transcript.
  * @module @deepseek-ai/dsh-session/repair
  */
 
@@ -39,36 +9,19 @@ import type { CallId } from '@deepseek-ai/dsh-llm'
 import type { SessionEvent } from './types.ts'
 
 /**
- * Scan `events` for an open turn/step at the tail and return the synthetic
- * boundary events that close them, with `seq` continuing the log and `time`
- * copied from the last real event (the closers stand in for the crash moment;
- * reusing the last timestamp keeps them deterministic and never invents a
- * "future" time). Returns an empty array when the log is already balanced
- * (ends on a `turn/end`, or is empty) — the common, non-crash case.
+ * Return deterministic synthetic events that close an open tail turn. Unmatched
+ * calls receive error results first, followed by an open `step/end` and an
+ * interrupted `turn/end`; sequences continue the log and timestamps reuse the
+ * last real event. A balanced or empty log returns no events.
  *
- * The closers, in order: an error `tool/result` for each unmatched `tool-call`
- * in the interrupted turn, then a `step/end` if a step is open, then the
- * `turn/end {interrupted}`. The tool-results come first so a step that issued
- * tool calls is balanced (every call has a result) before its `step/end`.
- *
- * Only the LAST turn can be open: the invariants plugin guarantees a `turn/end`
- * before any later `turn/start`, so an interior open turn is impossible in a
- * valid committed log. Likewise at most one step is open within that turn.
  * @param events - the loaded durable log to scan (a valid committed prefix, possibly with a crash tail).
  * @returns the synthetic closer events to append after `events`, in order; empty when the log is already balanced.
  */
 export function interruptedTurnClosers(events: readonly SessionEvent[]): SessionEvent[] {
   let openTurn: number | null = null
   let openStep: number | null = null
-  // Track tool calls vs. their results WITHIN the currently-open turn only: a
-  // call is "pending" until its matching tool/result arrives. Reset at every
-  // turn boundary so a committed earlier turn (already balanced) never leaks a
-  // phantom pending call into the interrupted-turn repair.
-  // Track pending tool calls with their callSeq (the seq of the `tool/call`
-  // event, captured for surface sourceEventSeqs provenance on the synthetic
-  // result). CallSeq is set from `tool/call` events; the assistant/message
-  // block scan may register a call first (it appears earlier in the log), and
-  // the later `tool/call` event fills in the seq.
+  // Reset at each turn boundary so earlier calls cannot leak into tail repair.
+  // Assistant blocks register calls; later tool/call events add provenance seqs.
   const pendingCalls = new Map<CallId, { step: number; callSeq?: number }>()
   for (const event of events) {
     switch (event.type) {
@@ -97,10 +50,7 @@ export function interruptedTurnClosers(events: readonly SessionEvent[]): Session
         }
         break
       case 'tool/call':
-        // Capture the tool/call event seq for surface provenance on the
-        // synthesized tool/result. The entry may already exist (registered by
-        // the assistant/message above) or may be new (if the assistant/message
-        // came from a prior step that was already closed).
+        // Add the tool/call seq used as provenance on a synthetic result.
         {
           const entry = pendingCalls.get(event.data.callId)
           if (entry) {
@@ -129,10 +79,8 @@ export function interruptedTurnClosers(events: readonly SessionEvent[]): Session
   const time = last.time
   const closers: SessionEvent[] = []
 
-  // Synthesize an error tool/result for each tool-call left unanswered by the
-  // crash, so deriveMessages() yields a valid provider transcript on resume (a
-  // dangling assistant tool-call is rejected by every provider). Insertion
-  // order follows the Map (insertion = log order of the assistant messages).
+  // Close calls before their step: providers reject dangling assistant calls,
+  // and Map insertion order preserves their transcript order.
   for (const [callId, { step, callSeq }] of pendingCalls) {
     closers.push({
       type: 'tool/result',

packages/core/session/src/request-header.ts

@@ -1,14 +1,7 @@
 /**
- * Request-header reconstruction utilities: the pure fold/diff/apply trio over
- * the `request/header` / `request/header-delta` session events. Anyone
- * holding a session log reconstructs the {@link EpochHeader} any request was
- * built under by folding these events in log order; the loop uses the same
- * functions to decide whether a step's header changed and to encode the
- * change. Deltas are an encoding optimization with a safety valve — the
- * writer round-trip-verifies every delta before appending and falls back to
- * a full snapshot when the encoding cannot express the change — so folding
- * never needs error recovery on a well-formed log.
- *
+ * Request-header reconstruction utilities over `request/header` snapshots and
+ * `request/header-delta` events. Writers round-trip each proposed delta and use
+ * a full snapshot when the encoding cannot represent the change.
  * @module dsh-session/request-header
  */
 
@@ -114,13 +107,10 @@ function applyTools(prev: readonly ToolSchema[], delta: ToolsDelta): ToolSchema[
 }
 
 /**
- * Field-wise equality over canonical headers — the cheap comparison the
- * writer's round-trip guard runs (`applyHeaderDelta(prev, delta)` must equal
- * the intended header) and the loop runs to skip logging an unchanged header.
- * Tools compare per-schema IN ORDER (canonical JSON), so a pure reordering is
- * correctly unequal; the session prefix compares as canonical JSON (both
- * sides come from the same build path, so key order matches when the values
- * do).
+ * Field-wise equality over canonical headers — the cheap comparison the writer's round-trip
+ * guard runs (`applyHeaderDelta(prev, delta)` must equal the intended header) and the loop
+ * runs to skip logging an unchanged header.
+ *
  * @param a - one canonical header.
  * @param b - the other.
  * @returns whether config, system, tools (in order), and the session prefix all match.
@@ -139,13 +129,12 @@ function sameMessages(a: readonly Message[] | undefined, b: readonly Message[] |
 }
 
 /**
- * Compute the `request/header-delta` payload between two canonical headers,
- * or undefined when they are equal. The caller MUST round-trip the result
- * ({@link applyHeaderDelta} on `prev` deep-equals `next`) before logging it —
- * the encoding cannot express every change (a pure tool reordering) — and
- * fall back to a full `request/header` snapshot when the check fails.
- * The session prefix is replaced whole (small advisory content, not worth
- * diffing); an empty replacement array encodes the transition to "none".
+ * Compute the `request/header-delta` payload between two canonical headers, or
+ * `undefined` when they are equal. The encoding cannot represent every change,
+ * including pure tool reordering, so callers must apply and compare the result
+ * before logging it and fall back to a full snapshot on mismatch. The session
+ * prefix is replaced whole; an empty array removes it.
+ *
  * @param prev - the folded header the log currently implies.
  * @param next - the header the next request will actually use.
  * @returns the delta payload, or undefined when nothing changed.
@@ -182,15 +171,13 @@ export function applyHeaderDelta(prev: EpochHeader, delta: HeaderDelta): EpochHe
 }
 
 /**
- * Fold the header events of a log (or any prefix of one) into the
- * {@link EpochHeader} in force after the last of them: each
- * `request/header` snapshot replaces the state, each `request/header-delta`
- * amends it. The pure, offline form of reconstruction — external tooling and
- * the dev invariant both use it; the live session tracks the same fold
- * incrementally.
+ * Fold the header events of a log (or any prefix of one) into the {@link EpochHeader} in
+ * force after the last of them: each `request/header` snapshot replaces the state, each
+ * `request/header-delta` amends it.
+ *
  * @param events - session events in log order (non-header events are skipped).
- * @param from - a previously folded state to continue from (the live session's
- *   incremental cursor); omit to fold from nothing.
+ * @param from - a previously folded state to continue from (the live session's incremental
+ *   cursor); omit to fold from nothing.
  * @returns the folded header, or undefined when no header event exists yet.
  */
 export function foldRequestHeader(events: readonly SessionEvent[], from?: EpochHeader): EpochHeader | undefined {

packages/core/session/src/surface.ts

@@ -23,12 +23,9 @@ const SURFACE_EVENT_TYPES = new Set<string>([
 ])
 
 /**
- * Whether an event's `type` is surface-eligible (one of the five
- * message-producing {@link SurfaceEventType} values). This is the TYPE check
- * only — it does NOT require `surfaceOp` to be present. Use it to detect a
- * surface-eligible event that is MISSING its mandatory marker (e.g. validating
- * a seed/load log); use {@link isSurfaceEvent} to narrow to a fully-formed
- * {@link SurfaceEvent} with `surfaceOp` present.
+ * Check only whether a type may enter the message surface; it does not require `surfaceOp`. This
+ * detects eligible seed/load events missing their mandatory marker. Use {@link isSurfaceEvent} to
+ * narrow a fully formed event whose marker is present.
  * @param type - the event type string to test.
  * @returns true when the type is one of the five message-producing types.
  */

packages/core/session/src/tool-pairing.ts

@@ -1,36 +1,7 @@
 /**
- * Tool-pairing balance over a session's SURFACE: is a given cut point in the
- * surface a safe edge for a collapsed region (e.g. compaction)?
- *
- * The invariant a consumer needs: a collapsed region must never separate an
- * `assistant/message`'s `tool-call` blocks from their answering `tool/result`s
- * — that would leave the rehydrated transcript with a dangling tool-call or an
- * orphaned tool-result, which every provider rejects. (This is the
- * compaction-time mirror of the crash-recovery imbalance that
- * {@link interruptedTurnClosers} repairs on load.) Steps were once used as a
- * proxy for this bracketing, but a compaction REWRITES the surface — it lands a
- * replacement node at a high log seq whose SURFACE position is the head — so a
- * scan over the LOG's `step/*` markers mis-reads such a node's neighbours. The
- * pairing the invariant actually protects lives in the surface nodes' own
- * content (a `tool-call` block's id, a `tool/result`'s `callId`), which travels
- * with the node through any reshaping, so alignment is decided over the surface
- * directly.
- *
- * A **cut** is a gap between two adjacent surface nodes (named by the node it
- * sits immediately before), or the after-tail gap (`null`). Walking the surface
- * head→tail and assigning each node a delta — `+1` per `tool-call` block on an
- * `assistant/message`, `-1` per `tool/result`, `0` otherwise — the depth at a
- * cut is the number of still-unanswered tool calls before it. A cut is
- * **balanced** when that depth is `0`. A region `[start..end]` is safe to
- * collapse iff BOTH its edges are balanced cuts: the cut before `start` and the
- * cut after `end`. Nodes that belong to no step (a pre-step `user/message`, an
- * inter-step `steering/message`, an injection `context/message`) carry no
- * pairing, contribute `0`, and so are free boundaries — exactly as before, but
- * now as a consequence of the balance rather than a special case. An open
- * trailing step (an assistant whose `tool/result`s have not landed yet) keeps
- * the depth positive through the tail, so no cut inside it is balanced — the
- * old explicit open-step check falls out of the same counter.
- *
+ * Tool-pairing balance over a session surface. Compaction changes surface
+ * positions, so safe cuts are derived from tool-call/result content on the
+ * surface rather than step markers in the append-only log.
  * @module @deepseek-ai/dsh-session/tool-pairing
  */
 
@@ -57,33 +28,14 @@ function nodeDelta(event: SessionEvent): number {
 }
 
 /**
- * Whether the surface prefix ending at the given cut has BALANCED tool-call /
- * tool-result brackets — i.e. every `tool-call` block on the surface before the
- * cut has its answering `tool/result` before the cut too, so the cut is a safe
- * edge for a collapsed region (it cannot split an assistant↔result pair).
- *
- * `nodes` is the surface linked list in head→tail order (e.g.
- * `session.surface.nodes`); `events` is the session log, used to look each
- * node's event up by `seq`. `beforeSeq` names the cut by the surface node it
- * sits immediately before; the after-tail cut (the whole surface) is `null`,
- * as is any `beforeSeq` not present on the surface.
- *
- * A region `[start..end]` is collapsible iff both edges are balanced cuts: call
- * `isToolPairingBalanced(nodes, events, start)` for the cut before `start`, and
- * `isToolPairingBalanced(nodes, events, after)` — where `after` is `end`'s
- * surface successor (`SurfaceNode.next`), or `null` when `end` is the tail —
- * for the cut after `end`.
- *
+ * Check that a surface cut does not split a tool call from its result. A region
+ * is safe to collapse only when the cuts before its first node and after its
+ * last node both return `true`.
  * @param nodes - the surface linked list in head→tail order.
  * @param events - the session log each node's `seq` indexes into.
- * @param beforeSeq - names the cut (the node it sits immediately before);
- *   `null` — or any seq not on the surface — means the after-tail cut.
- * @returns true when every `tool-call` before the cut is answered before it
- *   (the unanswered-call depth at the cut is zero).
- * @throws if the surface prefix drives the unanswered-call depth negative — a
- *   `tool/result` with no preceding open `tool-call` on the surface. That is a
- *   corrupt surface (a structural invariant violation), surfaced loudly here
- *   rather than silently mis-classifying a boundary.
+ * @param beforeSeq - node immediately after the cut; `null` or a seq absent from the surface means after-tail.
+ * @returns whether every call before the cut has its result before the cut.
+ * @throws if a result appears without a preceding open call.
  */
 export function isToolPairingBalanced(
   nodes: readonly SurfaceNode[],
@@ -93,14 +45,12 @@ export function isToolPairingBalanced(
   let depth = 0
   for (const node of nodes) {
     if (node.seq === beforeSeq) return depth === 0
-    // node.seq is a surface-node seq, always a valid log index by construction.
     // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
     depth += nodeDelta(events[node.seq]!)
     if (depth < 0) {
       throw new Error(`tool-pairing balance: tool/result at surface seq ${node.seq} has no matching tool-call (corrupt surface)`)
     }
   }
-  // Reached the after-tail cut (beforeSeq === null, or a seq not on the
-  // surface): the whole-surface prefix is balanced iff depth returned to 0.
+  // A missing cut node means the after-tail boundary.
   return depth === 0
 }

packages/core/session/src/types.ts

@@ -14,33 +14,17 @@ export function SessionId(id: string): SessionId {
 }
 
 /**
- * The on-disk session format version, stamped into every newly-written
- * {@link SessionHeader} and enforced by every persistence backend on load. The
- * single source of truth for the version — write sites and the load-time check
- * all read it.
- *
- * It is **`0`** deliberately: while the harness is unreleased the on-disk format
- * is **unstable / pre-release, with no compatibility implied**. Breaking changes
- * to the persisted {@link SessionEventMap} shape (folding fields onto an event,
- * removing a variant, …) happen freely and do NOT bump this — v0 absorbs all
- * pre-release churn, and a backend simply REJECTS any log not at v0 (there is no
- * migration; no persisted user data exists to preserve). A real, monotonically
- * bumped version policy begins at the first tagged release, when a specific
- * format boundary becomes worth distinguishing.
+ * The on-disk session format version, stamped into every newly-written {@link SessionHeader}
+ * and enforced by every persistence backend on load. The single source of truth for the
+ * version — write sites and the load-time check all read it.
+ * While the harness is unreleased it is pinned at `0`: no compatibility is
+ * implied, incompatible logs are rejected, and no migration is provided. A
+ * monotonic version policy starts with the first tagged release.
  */
 export const SESSION_FORMAT_VERSION = 0
 
 /**
- * Immutable session metadata — written once at creation and never rewritten.
- * {@link Session} enforces that contract at runtime: it validates and detaches
- * the accepted scalar fields, requires this header's id to match the session
- * id, and deep-freezes the published record.
- *
- * Kept SEPARATE from the event log deliberately: format-version, cwd, and
- * lineage are storage concerns, not conversation events, so they stay out of
- * {@link SessionEventMap} and never reach `deriveMessages()`. Every reference
- * system (pi's `version: 3` header, Codex's `SessionMeta`, Claude Code's tail
- * metadata) writes such a header.
+ * Immutable validated storage metadata, kept outside the conversation event log.
  */
 export interface SessionHeader {
   /**
@@ -58,13 +42,8 @@ export interface SessionHeader {
   /** The session this one was forked from (seed lineage), if any. */
   readonly parentSession?: SessionId
   /**
-   * How many leading events were INHERITED via a seed rather than produced by
-   * this session — the seed boundary. Set when a fork seeds a child with a
-   * prefix of the parent's log (= the seeded prefix length); absent/0 means the
-   * session produced all its own events. Persisted so a reload reconstructs the
-   * boundary instead of re-deriving it from the full stored log, and so a replay
-   * harness can skip the inherited prefix when deriving the child's OWN script
-   * (the seeded events are the parent's, not this child's model calls).
+   * How many leading events were inherited through a seed. Persisting this
+   * boundary lets resume and replay distinguish parent history from child work.
    */
   readonly seedLength?: number
 }
@@ -78,17 +57,8 @@ export interface CreateSessionOptions {
   /** Events to seed the new session with (replay/fork). */
   readonly seed?: readonly SessionEvent[]
   /**
-   * Creation metadata. The store reads this plain record and each accepted
-   * field once, then fills in `version`/`id` and defaults
-   * `createdAt` to now; the caller supplies the storage-level fields (validated
-   * absolute `cwd`, `parentSession` lineage, the seed boundary `seedLength`, and
-   * — when reconstructing a persisted session — the original `createdAt` to
-   * preserve it).
-   *
-   * `seedLength` is EXPLICIT, not inferred from `seed.length`: a reconstruction
-   * (resume/load) seeds the WHOLE stored log, so its `seed.length` is the full
-   * length, not the original boundary — the caller must pass the persisted
-   * boundary back. A fresh fork passes its actual seeded-prefix length.
+   * Storage metadata read once before publication. `seedLength` is explicit
+   * because a resumed seed contains the full stored log, not only its inherited prefix.
    */
   readonly meta?: {
     readonly cwd?: string
@@ -119,21 +89,7 @@ export interface TurnTriggerMap {
 export type TurnTrigger = TurnTriggerMap[keyof TurnTriggerMap]
 
 /**
- * Why a turn ended.
- * Merge-extensible sum type.
- *
- * `max-tokens` mirrors the model-call `FinishReasonMap` variant (DeepSeek's
- * `length`): the turn ended because a step hit the output-token ceiling, not
- * because the model chose to stop. The agent-loop surfaces it via the rule
- * "any `max-tokens` step in the turn makes the turn end `max-tokens`" (a
- * continuation plugin can run further steps after one, but the cut-short fact
- * still wins). It is distinct from `completed` so a consumer (e.g. the ACP
- * bridge mapping to `StopReason: 'max_tokens'`) can tell a clean stop from a
- * truncated one. The next variants to add — when an adapter/loop first emits
- * them — are `refusal` and `max_turn_requests` (both named by the ACP RFC as ACP
- * stop reasons); no current adapter produces a `refusal` finish (unknown
- * DeepSeek finish reasons collapse to `error`), so it is deliberately omitted
- * until one does.
+ * Why a turn ended. Merge-extensible sum type.
  */
 export interface TurnEndReasonMap {
   completed: { kind: 'completed' }
@@ -146,26 +102,16 @@ export interface TurnEndReasonMap {
    */
   error: { kind: 'error'; step: number; message: string; code?: string }
   disposed: { kind: 'disposed' }
+  /** At least one step reached its output-token ceiling, even if a plugin continued the turn. */
   'max-tokens': { kind: 'max-tokens' }
   /**
-   * The turn's entire prompt batch was BLOCKED before any step ran — every
-   * drained queued message was vetoed by an `agent/prompt-submit` listener (a
-   * hook). The turn still opened (so the boundary stays balanced and the block
-   * is a durable in-turn fact), but ran zero steps. `reason` carries the block
-   * message from the vetoing decision. Distinct from `aborted` (a user-driven
-   * cancel) and `error` (a failure): the prompt was rejected by policy, not
-   * interrupted or broken. A UI renders it as "prompt blocked by hook".
+   * Policy blocked every prompt before the first step. The zero-step turn still
+   * records a balanced durable boundary and the veto reason.
    */
   rejected: { kind: 'rejected'; reason: string }
   /**
-   * The turn never ended on its own: the process crashed mid-turn and a
-   * persistence backend later closed the orphaned (open) turn on reload so the
-   * log stays balanced. SYNTHESIZED by the backend's crash-recovery repair — no
-   * loop ever emits this. Its events are real (they were durably appended before
-   * the crash) and are PRESERVED, not discarded: a single turn can be huge in a
-   * long-horizon task (many steps, large tool output), so truncating it would
-   * lose real work. The marker records that the turn was cut short, not that the
-   * model completed it. See the session-persistence RFC.
+   * A persistence backend closed a crash-orphaned turn on reload. The loop never
+   * emits this marker, and the events recorded before the crash remain intact.
    */
   interrupted: { kind: 'interrupted' }
 }
@@ -192,15 +138,9 @@ export interface TodoItem {
 }
 
 /**
- * The request header: everything about an LLM request besides its derived
- * message history — the call configuration plus the rendered system prompt,
- * tool schemas, and the session prefix. Logged session state (the
- * reconstructability RFC): a
- * {@link SessionEventMap} `request/header` snapshot installs one, a
- * `request/header-delta` amends it, and folding those events over the log
- * (`foldRequestHeader`) reconstructs the header any request was built under.
- * Canonical form: an empty system prompt, an empty tool list, and an empty
- * prefix are ABSENT fields, matching how requests are built.
+ * Logged request state outside derived history: call config, system prompt,
+ * tools, and session prefix. Header snapshots and deltas reconstruct it;
+ * canonical empty optional fields are absent.
  */
 export interface EpochHeader {
   /** The conversation's call configuration (model + sampling scalars). */
@@ -262,24 +202,10 @@ export interface ToolsDelta {
 }
 
 /**
- * The session event vocabulary — the append-only source of truth for an
- * agent's whole interaction history. The LLM message history is *derived*
- * from this log; nothing else is authoritative. Replay = re-derive from the
- * same events; trace/telemetry = subscribe to the log.
- *
- * Merge-extensible: plugins declare extra event types via declaration merging
- * (e.g. the compaction plugin adds `'compact/start'`, `'compact/summary'`,
- * `'compact/end'`).
- *
- * Durability contract (what a persistence backend relies on): the durable log
- * persists every event verbatim, INCLUDING `assistant/chunk` — `seq` must stay
- * contiguous (`seq = log.length`), so chunks cannot be filtered out of the
- * canonical log. All `event.data` must be JSON-serializable — `Session.append`
- * (and the seed path in the constructor) enforces this at the source (throwing
- * on non-serializable data), so a bad event never enters the log and
- * `session.events` always equals what a backend can persist. Adding a new event
- * type that carries non-serializable data, or that breaks the turn/step nesting
- * the invariants plugin checks, is a breaking change to the on-disk format.
+ * The merge-extensible, append-only source of truth for an agent interaction.
+ * Message history is derived from this log. Every event is lossless JSON and
+ * sequence numbers stay contiguous, including raw chunks, so persistence can
+ * store the canonical log verbatim.
  */
 export interface SessionEventMap {
   /**
@@ -302,14 +228,8 @@ export interface SessionEventMap {
   /** A user-visible prompt (queued message drained at turn start). */
   'user/message': { content: ContentBlock[]; source: MessageSource }
   /**
-   * A queued prompt an `agent/prompt-submit` listener VETOED — the durable
-   * record of a blocked prompt and why. Appended in place of the `user/message`
-   * the prompt would have become, so the block survives replay even in a MIXED
-   * batch where another queued prompt is allowed (there the turn does not end
-   * `rejected`, so the boundary reason alone would not preserve it). `content`
-   * is the original prompt the listener rejected; `reason` is the veto text
-   * ({@link PromptDecision} `block.reason`). NOT a {@link SurfaceEventType}: a
-   * blocked prompt produces no LLM message and never reaches `deriveMessages()`.
+   * Durable record of a prompt veto and its reason. It is log-only: the blocked
+   * prompt never enters the model-visible surface, including in a mixed batch.
    */
   'prompt/blocked': { content: ContentBlock[]; source: MessageSource; reason: string }
   /**
@@ -346,47 +266,19 @@ export interface SessionEventMap {
   /** Steering content injected between steps of a running turn. */
   'steering/message': { turn: number; content: ContentBlock[]; source: MessageSource }
   /**
-   * The agent's whole todo list, carried as a full snapshot and replaced
-   * wholesale on each write — the current list is the most recent `todo/write`
-   * (last-write-wins on replay, no fold). Appended by an owning agent via
-   * `session.append('todo/write', { todos })`.
-   *
-   * NOT a {@link SurfaceEventType}: it produces no LLM message and never reaches
-   * `deriveMessages()`, so it carries no `surfaceOp` and stays off the surface —
-   * it is durable, replayable UI state, distinct from the conversation history.
-   * It is a `SessionEventMap` member riding the existing `session/event` emit,
-   * not a first-class Cordis `interface Events` notification, so it has no
-   * cordis-catalog row.
+   * Whole-list snapshot; the latest write wins on replay. It is log-only UI
+   * state and never enters derived model history.
    */
   'todo/write': { todos: TodoItem[] }
   /**
-   * Full snapshot of the {@link EpochHeader} the NEXT request is built under,
-   * with the {@link RequestHeaderReason} it was recorded whole. Appended by
-   * the loop inside the step, before dispatch, on a loop instance's first
-   * request-building step (`'initial'`/`'resume'`) or when a delta failed its
-   * round-trip guard (`'fallback'`); always records what the request actually
-   * used, post-`agent/request`. Anchors the header fold: reconstruction reads
-   * the latest snapshot and applies the deltas after it. NOT a
-   * {@link SurfaceEventType}: it produces no LLM message — it is the request
-   * envelope, logged so every request is a pure function of the session log
-   * (the reconstructability RFC).
+   * Full {@link EpochHeader} for the next request, appended inside its step
+   * before dispatch. It is log-only and anchors subsequent deltas.
    */
   'request/header': { header: EpochHeader; reason: RequestHeaderReason }
   /**
-   * Amendment to the folded {@link EpochHeader}: at least one of a
-   * {@link SystemDelta}, a {@link ToolsDelta}, a whole replacement
-   * {@link LlmCallConfig} (four scalars — not worth diffing), or a whole
-   * replacement session prefix (`messagePrefix` — small advisory content,
-   * replaced whole; an EMPTY array encodes the transition to "none",
-   * mirroring the canonical form's absent field — the loop never produces
-   * one in practice: the prefix is composed once per instance and anchored
-   * by that instance's snapshot, so this arm exists for codec totality).
-   * Appended by the
-   * loop inside the step, before dispatch, when the header for this request
-   * differs from the fold of the log so far; the writer verifies
-   * `applyHeaderDelta(previous, delta)` reproduces the new header exactly and
-   * falls back to a `'fallback'` `request/header` snapshot when it cannot, so
-   * a logged delta ALWAYS round-trips. NOT a {@link SurfaceEventType}.
+   * Log-only amendment to the folded {@link EpochHeader}. System and tools use
+   * their delta codecs; config and prefix replace whole, with an empty prefix
+   * encoding removal. Writers verify round-trip equality or log a fallback snapshot.
    */
   'request/header-delta': { system?: SystemDelta; tools?: ToolsDelta; config?: LlmCallConfig; messagePrefix?: Message[] }
 }
@@ -434,16 +326,8 @@ export type SurfaceOp =
   | { op: 'replace'; start: number; end: number }
 
 /**
- * Surface metadata passed to {@link Session.append}.
- * `surfaceOp` controls how the event enters the surface linked list;
- * `sourceEventSeqs` records the seq numbers of events that are provenance
- * sources of this one (e.g. the `assistant/chunk` seqs behind an
- * `assistant/message`, or the shadowed nodes behind a compaction replacement).
- *
- * Required for {@link SurfaceEventType} events — every message-producing event
- * MUST declare how it enters the surface, because the surface is the sole
- * source of derived history. Non-surface event types (`turn/start`,
- * `assistant/chunk`, `error`, …) cannot carry surface metadata.
+ * Surface placement and provenance for {@link Session.append}. Required on
+ * message-producing events and forbidden on log-only events.
  */
 export interface SurfaceIntent {
   surfaceOp: SurfaceOp

packages/core/session/tests/derived-cache.spec.ts

@@ -1,10 +1,7 @@
 /**
- * Derived-message cache tests: the session projects each surface node exactly
- * once (O(new nodes) per call), rebuilds on a surface replacement (the
- * replaceGeneration signal), returns a fresh array snapshot
- * per call over shared frozen messages, and stays deep-equal to a from-scratch
- * replay derivation at every step — the incremental==scratch property the
- * reconstructability RFC's invariant enforces in dev at request time.
+ * Derived-message cache contract against a scratch oracle: project new nodes
+ * once, rebuild on surface replacements, return fresh arrays over shared
+ * frozen messages, and remain value-equal to replay at every step.
  */
 
 import { describe, expect, it } from 'vitest'
@@ -28,7 +25,6 @@ describe('derived-message cache', () => {
     userText(session, 'two')
     session.append('assistant/message', { turn: 1, step: 1, content: [{ type: 'text', text: 'reply' }] }, { surfaceOp: 'append' })
     expect(session.deriveMessages()).toEqual(scratch(session))
-    // An empty-content assistant/message (usage host) projects to nothing.
     session.append('assistant/message', { turn: 1, step: 2, content: [], usage: { inputTokens: 1, outputTokens: 0 } }, { surfaceOp: 'append' })
     expect(session.deriveMessages()).toEqual(scratch(session))
   })
@@ -48,7 +44,6 @@ describe('derived-message cache', () => {
 
     expect(session.deriveMessages()).toHaveLength(1)
     expect(session.deriveMessages()).toEqual(scratch(session))
-    // The array a caller took before the replace is untouched.
     expect(beforeReplace).toHaveLength(2)
   })
 
@@ -61,7 +56,7 @@ describe('derived-message cache', () => {
     const second = session.deriveMessages()
     expect(first).toHaveLength(1)
     expect(second).toHaveLength(2)
-    // Shared projection objects: the same frozen message instance, once ever.
+    // Array snapshots share their frozen message projections.
     expect(second[0]).toBe(first[0])
     expect(Object.isFrozen(first[0])).toBe(true)
   })
@@ -73,8 +68,7 @@ describe('Session.deriveEventMessage — the per-event projection', () => {
     const session = new Session(SessionId('per-event'))
     session.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
     const event = session.append('user/message', { content: [{ type: 'text', text: 'hi' }], source: { kind: 'user' } }, { surfaceOp: 'append' })
-    // The fold path (deriveMessages) and the per-event path share the
-    // projection, so an external reconstructor cannot disagree with the cache.
+    // Full and per-event derivation share one projection.
     expect(session.deriveEventMessage(event)).toEqual(session.deriveMessages().at(-1))
   })
 

packages/core/session/tests/gen-persistence-catalog.spec.ts

@@ -1,16 +1,6 @@
 /**
  * Negative-path tests for the persistence log catalog generator
  * (`scripts/gen-persistence-catalog.ts`).
- *
- * The generated catalog is frozen by a regenerate-and-diff freshness gate, so
- * the freshness half is exercised by `pnpm run verify-persistence-catalog` in
- * CI. What a freshness diff CANNOT prove is that the generator REJECTS
- * malformed source the way it promises to — a member without description
- * prose, a forbidden `@mode` tag, a non-literal member name, a duplicate event
- * declaration, a missing or ambiguous `SurfaceEventType` union, a stale union
- * member. These tests drive the exported collectors against synthetic fixture
- * packages to prove each guard fires (and that well-formed declarations pass),
- * mirroring the gen-cordis-catalog negative tests.
  */
 
 import { mkdtempSync, mkdirSync, rmSync, writeFileSync } from 'node:fs'

packages/core/session/tests/properties.spec.ts

@@ -13,10 +13,8 @@ import { CallId } from '@deepseek-ai/dsh-llm'
 import { Session, SessionId } from '@deepseek-ai/dsh-session'
 import type { SessionEventMap, SessionEventType, SurfaceIntent } from '@deepseek-ai/dsh-session'
 
-// An appendable event: its type/data plus, for surface-eligible types, the
-// explicit surface intent the generator declares (mirroring how a real caller
-// passes it). The intent is part of the generated fixture, NOT synthesized by
-// `build`, so each arbitrary states the marker it produces.
+// Each arbitrary supplies its own surface intent; `build` must not synthesize
+// one or the property would fail to exercise malformed fixture choices.
 type Appendable = {
   [T in SessionEventType]: { type: T; data: SessionEventMap[T]; intent?: SurfaceIntent }
 }[SessionEventType]

packages/core/session/tests/repair.spec.ts

@@ -155,11 +155,8 @@ describe('interruptedTurnClosers', () => {
   })
 
   it('handles tool/call without a matching assistant/message entry gracefully', () => {
-    // A tool/call event exists in the log but no assistant/message registered
-    // the callId in pendingCalls (e.g., a plugin appended it directly, or the
-    // assistant/message from a prior step didn't have this call). The repair
-    // should still close the turn — it just won't synthesize a result for this
-    // call (there's nothing to answer).
+    // A raw tool/call with no assistant-registered pending call has nothing to
+    // answer; repair still closes the step and turn without synthesizing a result.
     const events: SessionEvent[] = [
       userTurnStart(1, 0),
       { type: 'step/start', seq: 1, time: 1, data: { turn: 1, step: 1 } },

packages/core/session/tests/session.spec.ts

@@ -81,9 +81,6 @@ describe('Session', () => {
     const before = structuredClone(session.events)
 
     // A misbehaving consumer tries to mutate the messages it was handed.
-    // Derived messages are frozen shared projections (cloned once off the
-    // log, then deep-frozen): every mutation attempt THROWS in strict mode —
-    // isolation by unrepresentability, not by per-call cloning.
     const messages = session.deriveMessages()
     const userBlock = messages[0]!.content[0]!
     expect(() => { if (userBlock.type === 'text') userBlock.text = 'HACKED' }).toThrow(TypeError)
@@ -132,11 +129,8 @@ describe('Session', () => {
   it('rejects a surface-eligible append with no surfaceOp marker (runtime guard for the union-widening loophole)', () => {
     const session = new Session(SessionId('s5b'))
     session.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
-    // The typed overload makes surfaceOp mandatory only when the type argument is
-    // a SPECIFIC SurfaceEventType literal. A caller iterating raw events widens it
-    // to the SessionEventType union, where the conditional rest collapses to
-    // optional — the exact shape `for (const e of log) append(e.type, e.data)`
-    // produces. Reproduce that here and assert the runtime guard rejects it.
+    // A widened SessionEventType bypasses the overload's conditional requirement,
+    // so the runtime guard must still reject the missing surface marker.
     const widenedType = 'user/message' as SessionEventType
     expect(() => session.append(widenedType, { content: [{ type: 'text', text: 'hi' }], source: { kind: 'user' } }))
       .toThrow(/surface-eligible and requires a surfaceOp marker/)
@@ -663,10 +657,8 @@ describe('SessionStore', () => {
   })
 
   it('enter() rejects a stale prepared session whose id is already live (no overwrite)', async () => {
-    // prepare()/enter() are public cross-package primitives that a caller may
-    // separate with arbitrary work. A stale prepared session must NOT overwrite
-    // a live store entry of the same id — its detach disposer would later delete
-    // the REAL session, breaking the store-uniqueness invariant.
+    // A stale prepared object must not replace the live same-id entry; its later
+    // detach would otherwise remove the wrong session.
     const ctx = new Context()
     await ctx.plugin(SessionStore)
     const stale = ctx.sessions.prepare(SessionId('racy'))

packages/core/session/tests/surface.spec.ts

@@ -115,14 +115,11 @@ describe('SurfaceManager', () => {
 
   it('rebuild with replace operation splices out shadowed nodes', () => {
     const s = surfaceSession()
-    // seq: 0=turn/start, 1=user, 2=assistant, 3=turn/end
-    // Surface nodes: seq 1 (user), seq 2 (assistant).
-    // Replace both with a compaction marker. Both 1 and 2 are valid surface seqs.
+    // Replace surface seqs 1 (user) and 2 (assistant) with the summary.
     s.append('assistant/message',
       { turn: 2, step: 1, content: [{ type: 'text', text: 'summary' }] },
       { surfaceOp: { op: 'replace', start: 1, end: 2 }, sourceEventSeqs: [1, 2] },
     )
-    // Now the surface should have just the compaction node.
     expect(s.surface.nodes.length).toBe(1)
     expect(s.surface.nodes[0]!.seq).toBe(4) // seq of the compaction marker
     expect(s.surface.nodes[0]!.prev).toBeNull()

packages/core/session/tests/tool-pairing.spec.ts

@@ -4,24 +4,9 @@ import { Session, SessionId, isToolPairingBalanced } from '../src/index.ts'
 import type { SessionEvent, SurfaceNode } from '../src/index.ts'
 
 /**
- * Unit coverage for the tool-pairing balance check. It decides whether a CUT in
- * the surface (a gap before a given surface node, or the after-tail gap) is a
- * safe edge for a collapsed region (compaction): a region must never split an
- * `assistant/message`'s tool-calls from their `tool/result`s. A cut is balanced
- * when no unanswered tool-call sits before it on the surface. Nodes belonging to
- * no step (pre-step user message, inter-step steering, injection context) are
- * pairing-neutral, so their cuts are free boundaries.
- *
- * The fixtures are built through a real {@link Session} so the surface linked
- * list is derived exactly as production does — including the non-monotonic
- * surface a `replace` op leaves (a compaction checkpoint at a high log seq
- * sitting at the surface head), which is the case the abandoned log-position
- * scan mis-classified.
- *
- * Builders mirror the agent loop's real append order: queued user messages land
- * BEFORE `step/start`; within a step the order is `assistant/message` then
- * `tool/result`(s); injection turns are a bare `turn/start → context/message →
- * turn/end` with no step.
+ * Unit coverage for compaction-cut safety: a cut is balanced only when it
+ * separates no assistant tool call from its result. Non-step nodes are neutral,
+ * and replace operations prove surface order—not raw log order—is authoritative.
  */
 
 const SURFACE = { surfaceOp: 'append' as const }
@@ -182,10 +167,8 @@ describe('isToolPairingBalanced — multiple tool calls in one assistant message
 })
 
 describe('isToolPairingBalanced — a mid-step injection context/message', () => {
-  // A background task-done inject() lands a context/message INSIDE an open step,
-  // between the assistant (with a tool-call) and its tool/result. It is
-  // pairing-neutral, so the cut on EITHER side of it is unbalanced (the call is
-  // still open across it) — it is NOT a free boundary in this position.
+  // The injected context is pairing-neutral, but both adjacent cuts remain
+  // unbalanced because the tool call is still open across them.
   function midStepInjection(): Session {
     const s = new Session(SessionId('mid-inject'))
     s.append('turn/start', { turn: 1, trigger: { kind: 'message', source: { kind: 'user' } } })
@@ -236,11 +219,8 @@ describe('isToolPairingBalanced on an injection turn (no step)', () => {
 })
 
 describe('isToolPairingBalanced — CBR-001: a head checkpoint left by a replace op', () => {
-  // The case the log-position scan got wrong. After a compaction, a replacement
-  // user/message lands at a HIGH log seq but sits at the SURFACE head, beside
-  // the still-open step whose events follow it in the log. It carries no
-  // tool-call/result pair (just summarized prose), so it must be a balanced cut
-  // on BOTH sides regardless of its log neighbours.
+  // A replacement checkpoint has a high log seq but sits at the surface head;
+  // its cuts are balanced regardless of later raw-log neighbors.
   function checkpointHeadedSession(): Session {
     const s = new Session(SessionId('checkpoint'))
     // A closed turn with a tool step → surface [u1, asst(call), result].
@@ -291,10 +271,8 @@ describe('isToolPairingBalanced — CBR-001: a head checkpoint left by a replace
   })
 
   it('end cut after the head checkpoint is balanced (it carries no tool pair)', () => {
-    // This is the exact assertion the log-position scan failed: the forward log
-    // scan from the checkpoint reached the open step's assistant/message and
-    // wrongly reported mid-step. The surface balance sees a neutral node whose
-    // following cut closes no open call.
+    // This is the exact assertion the log-position scan failed: the forward log scan from the
+    // checkpoint reached the open step's assistant/message and wrongly reported mid-step.
     const s = checkpointHeadedSession()
     expect(endBalanced(s, s.surface.nodes[0]!.seq)).toBe(true)
   })

packages/core/system-prompt/README.md

@@ -1,6 +1,6 @@
 # dsh-system-prompt
 
-System prompt assembly registry. Plugins contribute ordered text sections, tool-schema providers, and named prompt variables. The agent loop calls `assemble(context)` once per step, and `renderPrompt(assembly)` is the full system prompt the model sees. The plugin registers the harness-owned openers itself — the static `harness:identity` section and the global default `deployment:persona` section — so they remain available regardless of which loop plugin drives an agent. An agent-scoped contribution with the same persona name shadows that default for its agent.
+System prompt assembly registry. Plugins contribute ordered sections, tool schemas, and named variables. The loop assembles once per step and renders the result as the complete model prompt. This plugin owns the static harness identity and global deployment persona; an agent-scoped persona shadows the global default.
 
 ## Config
 
@@ -20,7 +20,7 @@ System prompt assembly registry. Plugins contribute ordered text sections, tool-
 
 ### Live events
 
-`system-prompt/assemble` is an expert cooperative seam: its returned assembly is authoritative, and a listener that replaces or removes entries owns preserving any active Code Mode or structured-output protocol. Prefer [`ToolRegistry.restrict()`](../tools/README.md) when tool filtering must stay aligned across model presentation, lookup, and execution. Registry change is the deliberately unfiltered notification that an assembly input changed, possibly for one scope; exact signatures, dispatch modes, and filtering contracts live in the generated [Cordis event catalog](../../../docs/cordis-catalog/events.md).
+`system-prompt/assemble` is authoritative; listeners that replace entries must preserve any active Code Mode or structured-output protocol. Use [`ToolRegistry.restrict()`](../tools/README.md) when filtering must stay aligned across presentation, lookup, and execution. Registry-change notifications are unfiltered. The generated [event catalog](../../../docs/cordis-catalog/events.md) owns signatures and dispatch contracts.
 
 ### Key types
 

packages/core/system-prompt/src/index.ts

@@ -1,13 +1,5 @@
 /**
- * System prompt assembly registry. Plugins contribute ordered text sections,
- * tool schema providers, and named prompt variables; `assemble(context)`
- * collates them through a waterfall that runs once per step, and `renderPrompt`
- * interpolates `{{variable}}` references into the final text.
- *
- * The harness-owned prompt openers live here too: this plugin registers the
- * static `harness:identity` section (order −100) and the deployment's
- * `deployment:persona` section (order 0, from its `persona` config), so they
- * exist for every agent regardless of which loop plugin drives it.
+ * Registry for ordered prompt sections, tool schemas, and prompt variables.
  *
  * @module @deepseek-ai/dsh-system-prompt
  */
@@ -25,58 +17,28 @@ declare module 'cordis' {
 
   interface Events {
     /**
-     * Waterfall around prompt assembly — mutate or extend the
-     * {@link PromptAssembly} (sections + tools + variables) before it is
-     * rendered. Bound to the {@link SystemPrompt} service; call `next()` to
-     * delegate.
-     *
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): the carrier is keyed
-     * by `context.scope` — a listener registered through `agent.ctx` fires only
-     * for that agent's assemblies; a plain plugin listener fires for every
-     * assembly (scope-less ones included, dispatched subject-less).
-     *
-     * The returned assembly is authoritative. This is an expert composition
-     * seam: a listener that removes or replaces another plugin's protocol
-     * contribution owns preserving that protocol's invariants.
-     * @param assembly - the assembly built from the registered sections, tool
-     *   providers, and variable providers; listeners may mutate it or return a
-     *   replacement.
-     * @param context - the per-assembly {@link AssembleContext} the caller
-     *   passed to {@link SystemPrompt.assemble} (e.g. which agent the prompt
-     *   is for), so a listener can filter or extend per agent.
+     * Expert waterfall over the assembled sections, tools, and variables.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): scoped listeners
+     * receive only that scope's assemblies. The returned value is authoritative.
+     * @param assembly - the mutable assembly built from registered providers.
+     * @param context - the caller's per-assembly context.
      * @mode waterfall
      */
     'system-prompt/assemble'(this: Scoped<SystemPrompt>, assembly: PromptAssembly, context: AssembleContext, next: () => Promise<PromptAssembly>): Promise<PromptAssembly>
     /**
-     * A section, tool provider, or variable provider was registered
-     * or unregistered (the assembly inputs changed — possibly for one scope
-     * only). An UNFILTERED registry-subject notification, deliberately not
-     * scope-filtered dispatch: a global change concerns every agent's next
-     * assembly, so a scoped listener subscribing here sees every change, not
-     * just its own scope's.
+     * Emitted when any prompt provider changes. This registry notification is
+     * unfiltered because a global change affects every scope.
      * @mode emit
      */
     'system-prompt/change'(): void
   }
 }
 
-/**
- * Per-assembly input: what one {@link SystemPrompt.assemble} call is FOR.
- * Merge-extensible and agnostic of who assembles — `@deepseek-ai/dsh-agent`
- * declares the `agent` field, so section text and variable providers can be
- * functions of the calling agent. Every field is optional by nature: a bare
- * `assemble()` (tests, diagnostics) carries an empty, scope-less context, and
- * providers must tolerate absent fields.
- */
+/** Merge-extensible context for one prompt assembly. */
 export interface AssembleContext {
   /**
-   * The scope layer this assembly resolves (`@deepseek-ai/dsh-scope`): scoped
-   * sections/variables/tool-providers registered through this key's context
-   * join the assembly (shadowing same-named global contributions), and the
-   * `system-prompt/assemble` waterfall dispatches in this scope. The agent
-   * loop sets it to the agent (alongside the `agent` DX field — never set
-   * `agent` without `scope`; the dev invariants flag the mismatch). Absent =
-   * a scope-less assembly: global layer only, subject-less dispatch.
+   * Scope whose providers and waterfall listeners participate. When absent,
+   * only global providers and subject-less listeners participate.
    */
   scope?: ScopeKey
 }
@@ -107,16 +69,7 @@ export interface AssembledSection {
   text: string
 }
 
-/**
- * What one tool-schema provider contributes to an assembly
- * ({@link SystemPrompt.tools}). `schemas` is the provider's POST-restriction
- * visible set for the assembly's scope — exactly what the model may be shown.
- * `knownNames` is its PRE-restriction name universe: the set configured names
- * (`toolOrder`) are validated against, so a config typo fails loud while a
- * restricted-away tool stays a normal, non-erroneous absence. Omitted,
- * `knownNames` defaults to the names of `schemas` (right for providers with no
- * restriction concept).
- */
+/** Tool schemas visible in one assembly and their pre-restriction name set. */
 export interface ToolProviderResult {
   /** The schemas this provider contributes to THIS assembly. */
   readonly schemas: readonly ToolSchema[]
@@ -125,20 +78,8 @@ export interface ToolProviderResult {
 }
 
 /**
- * The assembled prompt.
- *
- * Tool schemas are part of the assembly by design: "what the model is told it
- * can do" is one coherent thing managed here, even though adapters transmit
- * `tools` as a separate wire field rather than prompt text. They arrive in
- * the canonical model-facing order (see {@link Config.toolOrder}).
- *
- * `variables` carries every registered prompt variable resolved against this
- * assembly's context — key present means registered, `undefined` value means
- * "no value for this assembly" (referencing it renders an error). Section
- * texts are resolved but NOT yet interpolated; {@link renderPrompt} applies
- * the variables, so waterfall listeners can still add sections or variables.
- *
- * Merge-extensible: plugins can declare extra fields on this interface.
+ * Merge-extensible assembled prompt. Sections remain uninterpolated until
+ * {@link renderPrompt}; tools are already in canonical model-facing order.
  */
 export interface PromptAssembly {
   sections: AssembledSection[]
@@ -152,22 +93,12 @@ const VARIABLE_NAME = /^[a-z][a-z0-9_]*$/
 /** A complete `{{...}}` reference group at the scan position (validated after). */
 const GROUP_AT = /^\{\{([^{}]*)\}\}/
 
-/**
- * The rest entry for {@link Config.toolOrder}: the position where registered
- * tools not named in the list are inserted (in lexicographic name order).
- * Reserved: collected tool schemas using this name are rejected before
- * ordering, so the marker can never collide with a real model-facing tool.
- */
+/** Reserved {@link Config.toolOrder} marker for unlisted tools. */
 export const TOOL_ORDER_REST = '<unlisted-tools>'
 
 /**
- * Validate a configured tool-order list's shape at service construction:
- * the {@link TOOL_ORDER_REST} rest entry exactly once, no duplicate names.
- * Returns the list (or undefined when unconfigured); throws otherwise,
- * failing the service at load — a bad order config must never reach an
- * assembly. Whether every listed name matches a registered tool is checked
- * at each assembly instead ({@link orderTools}): tool plugins register after
- * this service constructs, so the tool set does not exist yet here.
+ * Validate duplicate names and the required {@link TOOL_ORDER_REST} marker.
+ * Registered names are checked later because plugins have not loaded yet.
  */
 function validateToolOrder(toolOrder: string[] | undefined): string[] | undefined {
   if (toolOrder === undefined) return undefined
@@ -183,20 +114,9 @@ function validateToolOrder(toolOrder: string[] | undefined): string[] | undefine
 }
 
 /**
- * Order collected tool schemas by the validated policy: with no configured
- * list, plain lexicographic name order; with one, listed names take their
- * listed position and every unlisted tool lands at the
- * {@link TOOL_ORDER_REST} rest entry in lexicographic name order. A listed
- * name outside `knownNames` — the providers' PRE-restriction name universe —
- * throws: misconfiguration fails loud, and each assembly is the earliest
- * moment the registered tool set exists to check against (tool plugins
- * register after the service constructs, so load time is too early); the
- * assembly rejects, failing the caller's turn before any model request. A
- * listed name that is KNOWN but not collected (a tool restricted away for
- * this assembly's scope) is a normal absence: its position simply
- * contributes nothing — `toolOrder` stays compatible with per-agent
- * `restrict()` masks. Never drops a collected tool, and both sorts are
- * stable, so tools sharing a name keep their collection order.
+ * Apply configured tool order, inserting unlisted tools lexicographically at
+ * {@link TOOL_ORDER_REST}. Unknown configured names fail; known but restricted
+ * names may be absent.
  */
 function orderTools(tools: ToolSchema[], toolOrder: string[] | undefined, knownNames: ReadonlySet<string>): ToolSchema[] {
   const reserved = tools.find(tool => tool.name === TOOL_ORDER_REST)
@@ -222,62 +142,25 @@ function compareToolNames(a: ToolSchema, b: ToolSchema): number {
 /** Plugin config: the deployment-authored fragment of the system prompt (see {@link Config.persona} for its contract). */
 export interface Config {
   /**
-   * The deployment's persona — the ONE deployment-authored fragment of the
-   * system prompt, rendered as the order-0 `deployment:persona` section
-   * (after the harness identity, before all tool guidance). Every agent in
-   * the context shares it by default; a per-agent persona is a SCOPED section
-   * of the same name registered through that agent's `agent.ctx` (it shadows
-   * this one for that agent — the subagent seam's `persona` request field does
-   * exactly that). Template, not free-form text:
-   * every complete `{{…}}` group is interpreted strictly against the
-   * registered prompt variables (the shipped agent loop registers `{{model}}`
-   * and `{{cwd}}`), and there is no escape syntax for literal `{{…}}` prose
-   * yet (a deliberate deferral; see the prompt-variables RFC). Defaults to
-   * `''` — the empty section is dropped at render, so a persona-less
-   * deployment opens with the harness identity alone.
+   * Deployment-wide order-0 persona template. A scoped section named
+   * `deployment:persona` shadows it; `{{variable}}` references are strict.
    */
   persona?: string
   /**
-   * Explicit model-facing tool order, as a list of `ToolSchema.name`s: listed
-   * tools take their listed position, and tools absent from the list are
-   * inserted at the {@link TOOL_ORDER_REST} (`'<unlisted-tools>'`) entry in
-   * lexicographic name order. A configured list must contain the rest entry
-   * exactly once, no duplicate names, and no name without a registered tool —
-   * a misconfigured order blocks work instead of silently reaching a model
-   * request: shape violations throw at load, and an unregistered name rejects
-   * every assembly. `TOOL_ORDER_REST` is reserved for the list marker and may
-   * not be a collected tool name; such a provider output also rejects the
-   * assembly. The single assembly-time validation rejects either failure
-   * before any model request — the earliest moment the registered tool set
-   * exists to check against, since tool plugins register after this service
-   * constructs. When omitted, tools are ordered lexicographically by name.
-   * Applied to the tools
-   * {@link SystemPrompt.assemble} collects, BEFORE the
-   * `system-prompt/assemble` waterfall — like the sections' `order` sort, it
-   * canonicalizes what the registry contributed (registration order is a
-   * plugin-load artifact); a waterfall listener that mutates the tool list
-   * owns the determinism of what it emits. Rationale (and why not per-plugin
-   * weights): docs/rfc/implemented/feature/2026-07-06-explicit-tool-order.md.
+   * Model-facing tool names in order, with {@link TOOL_ORDER_REST} exactly once.
+   * Shape errors fail at load and unknown names fail at assembly; known names
+   * hidden in one scope may be absent there. Omitted means lexicographic order.
    */
   toolOrder?: string[]
 }
 
 /**
- * Renders the text part of an assembly: interpolates `{{variable}}`
- * references in each section from `assembly.variables`, drops empty sections,
- * and joins the rest with blank lines.
- *
- * Strict by design (fail loud beats shipping a malformed prompt): a reference
- * to an unregistered variable, to a registered variable with no value for
- * this assembly, a complete `{{…}}` group that is not a well-formed variable
- * name (e.g. `{{ model }}`), or a `{{` that does not open a complete group
- * while a `}}` still follows (e.g. `{{{model}}}`, `{{a{b}}`) all throw. A
- * lone `{{` with no `}}` anywhere after it is ordinary prose and passes
- * through verbatim. Substituted values are never re-scanned.
- * @param assembly - the assembly to render (typically the awaited result of
- *   {@link SystemPrompt.assemble}); only `sections` and `variables` are read.
- * @returns the full system prompt text; `''` when every section renders empty
- *   (the caller then sends no system prompt at all).
+ * Interpolate strict `{{variable}}` references, drop empty sections, and join
+ * the rest with blank lines. Malformed, unknown, or undefined references throw;
+ * a lone `{{` without any later `}}` is literal prose, and substituted values
+ * are not scanned again.
+ * @param assembly - the assembly whose sections and variables to render.
+ * @returns the rendered prompt, or `''` when all sections are empty.
  */
 export function renderPrompt(assembly: PromptAssembly): string {
   return assembly.sections
@@ -294,10 +177,7 @@ function interpolate(section: AssembledSection, variables: Record<string, string
   for (let open = text.indexOf('{{'); open >= 0; open = text.indexOf('{{', last)) {
     const group = GROUP_AT.exec(text.slice(open))
     if (group === null) {
-      // No complete simple group starts at this `{{`. A `}}` further on means
-      // a mangled reference (extra or nested braces) — fail loud. With no
-      // closing `}}` anywhere after, it is ordinary prose (shell, JSON) and
-      // passes through verbatim.
+      // A later closing brace makes this malformed; otherwise it is literal prose.
       if (text.indexOf('}}', open + 2) >= 0) {
         throw new Error(`malformed prompt variable reference at "${text.slice(open, open + 16)}…" in section "${section.name}" (references are complete simple {{name}} groups)`)
       }
@@ -305,15 +185,12 @@ function interpolate(section: AssembledSection, variables: Record<string, string
       last = open + 2
       continue
     }
-    // group[0] is the whole `{{...}}` match (a plain string, no optional
-    // index): the name is its interior. `{{}}` yields '' → the malformed path.
+    // `{{}}` yields an empty name and follows the malformed-reference path.
     const name = group[0].slice(2, -2)
     if (!VARIABLE_NAME.test(name)) {
       throw new Error(`malformed prompt variable reference "{{${name}}}" in section "${section.name}" (variable names match ${String(VARIABLE_NAME)})`)
     }
-    // Object.hasOwn, NOT `in`: `in` walks the prototype chain, so an
-    // unregistered `{{constructor}}` would resolve to Object.prototype's and
-    // splice a function's source text into the prompt instead of throwing.
+    // Do not resolve unregistered names through Object.prototype.
     if (!Object.hasOwn(variables, name)) {
       const known = Object.keys(variables)
       throw new Error(`unknown prompt variable "{{${name}}}" in section "${section.name}"; registered variables: ${known.length > 0 ? known.join(', ') : '(none)'}`)
@@ -328,22 +205,11 @@ function interpolate(section: AssembledSection, variables: Record<string, string
   return result + text.slice(last)
 }
 
-/**
- * Registry service (`ctx.systemPrompt`): plugins contribute ordered text
- * sections, tool-schema providers, and named prompt variables; the agent loop
- * calls `assemble(context)` once per step. Registers the harness-owned
- * `harness:identity` and `deployment:persona` sections itself (see
- * {@link Config.persona}).
- */
+/** Registry service for the prompt inputs assembled before each model step. */
 export class SystemPrompt extends Service {
   static Config: z<Config> = z.object({
     persona: z.string().default(''),
-    // A schemastery array defaults to [] when omitted, but an omitted
-    // toolOrder must stay absent ("lexicographic order"), not become an
-    // explicitly-configured empty list (which is invalid — it lacks the
-    // rest entry). Forcing the default to undefined keeps the key out of the
-    // validated config; the cast is needed because .default() expects the
-    // array type.
+    // Preserve omission because an explicit empty order lacks the rest marker.
     toolOrder: z.array(z.string()).default(undefined as unknown as string[]),
   })
 
@@ -359,12 +225,7 @@ export class SystemPrompt extends Service {
   constructor(ctx: Context, config: Config) {
     super(ctx, 'systemPrompt')
     this.toolOrder = validateToolOrder(config.toolOrder)
-    // The harness-owned openers. They live HERE (not on the loop plugin) so a
-    // deployment that swaps in a different loop keeps them: the identity is a
-    // harness fact stated ahead of everything, and the persona is the
-    // deployment's config, one section of the full prompt, never the whole.
-    // An empty persona still RESERVES the section name (one owner — a plugin
-    // re-registering it throws); renderPrompt drops the empty text.
+    // Keep harness-owned openers independent of the selected loop plugin.
     this.section({
       name: 'harness:identity',
       order: -100,
@@ -373,30 +234,18 @@ export class SystemPrompt extends Service {
     this.section({
       name: 'deployment:persona',
       order: 0,
-      // The schema already defaulted an omitted persona to ''; the ?? only
-      // narrows the optional-input TYPE, it never supplies a different value.
+      // The fallback narrows the optional input type; the schema already defaults it.
       text: config.persona ?? '',
     })
   }
 
   /**
-   * Contribute a text section to the system prompt. Order is determined by
-   * `section.order` (ascending). The layer is decided by the CALLING context
-   * (`@deepseek-ai/dsh-scope`): a plain plugin context contributes globally; a
-   * scoped context (`agent.ctx`) contributes to that scope alone — and a
-   * scoped section SHADOWS a same-named global section for that scope's
-   * assemblies (most-specific-wins; this is how a per-agent persona overrides
-   * `deployment:persona`). The readonly typed contribution is borrowed until
-   * disposal; only the semantic
-   * finite-order rule is checked at runtime. Throws if the SAME layer already has the name (a
-   * duplicate would silently double prompt text — e.g. a double-loaded tool
-   * plugin; the global-duplicate message names `agent.ctx` as the per-agent
-   * alternative). Removed when the calling fiber is disposed. Emits
-   * `system-prompt/change` on register/unregister.
-   * @param section - the section to contribute (name, order, text or provider).
-   * @returns the disposer that removes the section. The exact
-   *   Cordis effect disposer (single-shot): composite (generator) effects may
-   *   yield it directly — exact identity nests the teardown in order.
+   * Register an ordered prompt section in the calling context's scope. A scoped
+   * section shadows a global section with the same name; duplicates within one
+   * layer and non-finite orders throw. Registration and disposal emit
+   * `system-prompt/change`.
+   * @param section - the section to register.
+   * @returns the exact Cordis effect disposer.
    */
   section(section: PromptSection): () => void {
     if (!Number.isFinite(section.order)) {
@@ -417,10 +266,7 @@ export class SystemPrompt extends Service {
           : `prompt section "${section.name}" is already registered in this scope`)
       }
       layer.push(section)
-      // Yield the rollback BEFORE emitting `system-prompt/change`: a generator
-      // effect collects each yielded disposer before the next step runs, so a
-      // throwing change listener removes the section instead of leaking it into
-      // every future assembly.
+      // Install rollback before notifying listeners that may throw.
       yield () => {
         const index = layer.indexOf(section)
         /* v8 ignore next 3 -- defensive: section was registered, so indexOf is guaranteed >= 0 */
@@ -430,31 +276,17 @@ export class SystemPrompt extends Service {
       }
       this.ctx.emit('system-prompt/change')
     }.bind(this), 'systemPrompt.section()')
-    // The EXACT cordis effect disposer, not a wrapper: a composite (generator)
-    // effect that owns a teardown ORDER must be able to yield THIS function —
-    // cordis nests a disposer out of the fiber's concurrent sibling list by
-    // exact function identity, so a wrapper would silently break the nesting
-    // (the agents.register() lesson). Cleanup is synchronous because this
-    // registration installs only synchronous state and notifications.
+    // Return the exact disposer so composite effects preserve teardown order.
     // eslint-disable-next-line @typescript-eslint/no-misused-promises -- synchronous cleanup; direct return preserves disposer identity
     return dispose
   }
 
   /**
-   * Contribute a tool-schema provider, evaluated at each assembly call with
-   * that assembly's {@link AssembleContext} (so it reflects the live registry
-   * state AND the assembly's scope — see {@link ToolProviderResult} for the
-   * `schemas`/`knownNames` split). The layer is decided by the calling
-   * context: a scoped provider (registered through `agent.ctx`) is consulted
-   * only for that scope's assemblies. Removed when the calling fiber is
-   * disposed. A provider must not return a schema named
-   * {@link TOOL_ORDER_REST}; that name is reserved for
-   * {@link Config.toolOrder}'s rest entry and rejects the assembly. Emits
-   * `system-prompt/change`.
-   * @param provider - evaluated at every {@link assemble} for fresh schemas.
-   * @returns the disposer that removes the provider. The exact
-   *   Cordis effect disposer (single-shot): composite (generator) effects may
-   *   yield it directly — exact identity nests the teardown in order.
+   * Register a tool-schema provider in the calling context's scope. Global and
+   * matching scoped providers both contribute; returning the reserved
+   * {@link TOOL_ORDER_REST} name makes assembly fail.
+   * @param provider - evaluated for each assembly with its context.
+   * @returns the exact Cordis effect disposer.
    */
   tools(provider: (context: AssembleContext) => ToolProviderResult): () => void {
     const scope = scopeOf(this.ctx)
@@ -467,7 +299,7 @@ export class SystemPrompt extends Service {
           return created
         })()
       layer.push(provider)
-      // Yield the rollback BEFORE emitting `system-prompt/change` (see section()).
+      // Install rollback before notifying listeners that may throw.
       yield () => {
         const index = layer.indexOf(provider)
         /* v8 ignore next 3 -- defensive: provider was registered, so indexOf is guaranteed >= 0 */
@@ -477,33 +309,18 @@ export class SystemPrompt extends Service {
       }
       this.ctx.emit('system-prompt/change')
     }.bind(this), 'systemPrompt.tools()')
-    // The EXACT cordis effect disposer, not a wrapper: a composite (generator)
-    // effect that owns a teardown ORDER must be able to yield THIS function —
-    // cordis nests a disposer out of the fiber's concurrent sibling list by
-    // exact function identity, so a wrapper would silently break the nesting
-    // (the agents.register() lesson). Cleanup is synchronous because this
-    // registration installs only synchronous state and notifications.
+    // Return the exact disposer so composite effects preserve teardown order.
     // eslint-disable-next-line @typescript-eslint/no-misused-promises -- synchronous cleanup; direct return preserves disposer identity
     return dispose
   }
 
   /**
-   * Contribute a named prompt variable, referenced from section text as
-   * `{{name}}`. The provider is evaluated at each assembly with that
-   * assembly's {@link AssembleContext}; returning `undefined` means "no value
-   * for this assembly" (a section referencing it then fails to render — a
-   * deployment must not claim facts it does not have). The layer is decided
-   * by the calling context: a scoped variable (registered through
-   * `agent.ctx`) resolves only for that scope's assemblies and SHADOWS a
-   * same-named global variable there. Throws on a name that does not match
-   * `[a-z][a-z0-9_]*` (it could never be referenced) or one already registered
-   * in the SAME layer. Removed when the calling fiber is disposed; emits
-   * `system-prompt/change` on register/unregister.
-   * @param name - the reference name (matches `[a-z][a-z0-9_]*`).
-   * @param provider - evaluated at every {@link assemble} for the value.
-   * @returns the disposer that removes the variable. The exact
-   *   Cordis effect disposer (single-shot): composite (generator) effects may
-   *   yield it directly — exact identity nests the teardown in order.
+   * Register a prompt variable in the calling context's scope. Scoped values
+   * shadow globals; invalid or duplicate names throw. A provider may return
+   * `undefined`, but rendering a section that references that value then fails.
+   * @param name - the `[a-z][a-z0-9_]*` reference name.
+   * @param provider - evaluated for each assembly.
+   * @returns the exact Cordis effect disposer.
    */
   variable(name: string, provider: (context: AssembleContext) => string | undefined): () => void {
     if (!VARIABLE_NAME.test(name)) {
@@ -524,7 +341,7 @@ export class SystemPrompt extends Service {
           : `prompt variable "${name}" is already registered in this scope`)
       }
       layer.set(name, provider)
-      // Yield the rollback BEFORE emitting `system-prompt/change` (see section()).
+      // Install rollback before notifying listeners that may throw.
       yield () => {
         layer.delete(name)
         if (scope !== undefined && layer.size === 0) this.scopedVariableProviders.delete(scope)
@@ -532,47 +349,22 @@ export class SystemPrompt extends Service {
       }
       this.ctx.emit('system-prompt/change')
     }.bind(this), 'systemPrompt.variable()')
-    // The EXACT cordis effect disposer, not a wrapper: a composite (generator)
-    // effect that owns a teardown ORDER must be able to yield THIS function —
-    // cordis nests a disposer out of the fiber's concurrent sibling list by
-    // exact function identity, so a wrapper would silently break the nesting
-    // (the agents.register() lesson). Cleanup is synchronous because this
-    // registration installs only synchronous state and notifications.
+    // Return the exact disposer so composite effects preserve teardown order.
     // eslint-disable-next-line @typescript-eslint/no-misused-promises -- synchronous cleanup; direct return preserves disposer identity
     return dispose
   }
 
   /**
-   * Assemble the current prompt for one caller: the global layer merged with
-   * {@link AssembleContext.scope}'s layer (scoped sections/variables SHADOW
-   * same-named global ones — most-specific-wins) — section texts resolved
-   * against `context` and sorted by order across the union, tools collected
-   * from the global providers plus the scope's and put in the canonical
-   * model-facing order ({@link Config.toolOrder}, or lexicographic name order
-   * when unconfigured — provider registration order is a plugin-load artifact
-   * and never reaches the assembly; a configured order naming a tool outside
-   * the providers' `knownNames` universe rejects the assembly, while a known
-   * name restricted away for this scope is a normal absence), and every
-   * visible variable resolved against `context` into `assembly.variables`.
-   * Tool schemas are detached because assembly waterfalls may mutate them.
-   * Runs through the `system-prompt/assemble` waterfall, giving listeners the
-   * opportunity to mutate or replace the assembly; the returned value is the
-   * authoritative model-visible composition. Like the sections' `order`
-   * sort, tool canonicalization happens on the initial assembly; listener
-   * output owns its own determinism. Await the result before reading the
-   * assembly values — waterfall listeners may be async.
-   * Interpolation happens later, in {@link renderPrompt}.
-   * @param context - what this assembly is for (defaults to an empty context;
-   *   see {@link AssembleContext}).
-   * @returns the assembly after the waterfall has run.
+   * Assemble global and scoped providers, detach tool parameters, apply
+   * canonical ordering, then run the assembly waterfall. Scoped sections and
+   * variables shadow globals; the returned waterfall value is authoritative.
+   * @param context - the optional scope and plugin-defined assembly fields.
+   * @returns the authoritative post-waterfall assembly.
    */
-  // async so the misconfigured-toolOrder throw in orderTools surfaces as a
-  // rejection: a Promise-returning method must not throw synchronously
-  // (`assemble().catch(...)` would miss it).
+  // Keep configuration failures on the declared asynchronous error path.
   async assemble(context: AssembleContext = {}): Promise<PromptAssembly> {
     const scope = context.scope
-    // Variables: global layer first, then the scope's layer OVERWRITES
-    // same-named entries (shadowing — a per-agent value wins for that agent).
+    // Scoped variables shadow globals.
     const variables: Record<string, string | undefined> = {}
     for (const [name, provider] of this.variableProviders) {
       variables[name] = provider(context)
@@ -581,21 +373,13 @@ export class SystemPrompt extends Service {
     for (const [name, provider] of scopedVariables ?? []) {
       variables[name] = provider(context)
     }
-    // Sections: merge by name, scoped REPLACING same-named global entries
-    // (most-specific-wins — the per-agent persona mechanism), then sort by
-    // order across the union. Registration order within a layer is preserved
-    // for equal orders (stable sort).
+    // Scoped sections shadow globals before the stable order sort.
     const sectionByName = new Map<string, PromptSection>()
     for (const section of this.sections) sectionByName.set(section.name, section)
     for (const section of (scope === undefined ? [] : this.scopedSections.get(scope)) ?? []) {
       sectionByName.set(section.name, section)
     }
-    // Tools: consult the global providers plus the scope's, each with this
-    // assembly's context. `schemas` are what the model may see (already
-    // post-restriction, per provider); `knownNames` (defaulting to the
-    // schemas' names) form the pre-restriction universe `toolOrder` is
-    // validated against, so a restricted-away tool is a normal absence while
-    // a config typo still fails every assembly loudly.
+    // Validate order against pre-restriction names while collecting visible schemas.
     const providers = [
       ...this.toolProviders,
       ...(scope === undefined ? [] : this.scopedToolProviders.get(scope)) ?? [],

packages/core/tools/README.md

@@ -11,16 +11,16 @@ tools:
   mode: native   # native (default) | code | both
 ```
 
-`native` contributes the calling agent's visible end capabilities as wire function definitions. Under `code`, this registry contributes the reserved `run_code` transport plus the generated `tools:sdk` prompt section (see [Code Mode](#code-mode)); `both` contributes the visible native definitions and both infrastructure pieces. Restrictions cannot remove `run_code`, and registering, shadowing, or explicitly filtering that reserved name fails loudly. An expert `system-prompt/assemble` listener may replace any prompt or schema contribution; its returned assembly is authoritative, so the listener owns preserving Code Mode when the protocol should remain active. Non-native modes require a loaded `ctx.codeRuntime` with `language: 'typescript'`; a missing or mismatched runtime rejects every prompt assembly with an actionable error, and a `systemPrompt.toolOrder` naming tools the mode no longer contributes rejects the assembly the same way.
+`native` contributes visible tools as function definitions. `code` contributes the reserved `run_code` transport and generated `tools:sdk` section; `both` contributes both forms. The reserved transport cannot be registered, shadowed, restricted, or removed. Non-native modes require a TypeScript `ctx.codeRuntime`, and a `systemPrompt.toolOrder` entry for a tool the mode does not contribute rejects prompt assembly. A `system-prompt/assemble` listener may replace the registry's contributions; its returned assembly is authoritative, so that listener owns preserving a usable Code Mode protocol.
 
 ### Public API
 
 - `ctx.tools.register(definition: ToolDefinition): () => void` Register a trusted typed same-process definition. The layer is the calling context's scope: a plain plugin context registers globally; an agent's `agent.ctx` registers for that agent alone, shadowing a same-named global tool there. Duplicate names within one layer throw; non-native modes also reject the reserved `run_code` transport name. `timeoutMs`, when present, must be positive and finite. Disposed with the calling fiber.
-- `ctx.tools.restrict(filter: ToolRestriction): () => void` Scoped-only (throws on a plain context): mask the global end-capability surface for the calling agent — `allow` keeps only the listed global tools, `deny` removes them; multiple restrictions intersect; scope-local registrations are merged afterward. The readonly arrays compile once into private sets. Every listed name must exist in the current pre-restriction global registry; scope-local, unknown, and reserved `run_code` names fail loudly. A deny-list admits a later global tool unless it names that tool; an allow-list excludes later names; neither filters a later scope-local registration. `restrict({})` rejects. This is live registration composition, not a parent-derived authority ceiling; see the [agent-scope security non-goal](../../../docs/rfc/implemented/architecture/2026-07-08-agent-scope-contexts.md#security-and-authority-are-explicit-non-goals).
+- `ctx.tools.restrict(filter)` applies an agent-scoped allow/deny mask to global tools and throws from a plain context. The filter is snapshotted at registration; multiple masks intersect and scope-local tools merge afterwards. Deny masks admit later unnamed globals, while allow masks exclude later names. Unknown, local, or reserved names and empty filters reject. This is live visibility composition, not an authority boundary; see the [scope security non-goal](../../../docs/rfc/implemented/architecture/2026-07-08-agent-scope-contexts.md#security-and-authority-are-explicit-non-goals).
 - `ctx.tools.get(name: string, scope?: ScopeKey): ToolDefinition | undefined` Resolution as one scope sees it (shadowing applied; a restricted-away global reads as absent) — presenters pass the calling agent so the card matches what executed.
 - `ctx.tools.schemas(scope?: ScopeKey): ToolSchema[]` Schemas of everything the scope can see (without the `execute` functions). The shipped tools' schemas are catalogued in [docs/tool-catalog.md](../../../docs/tool-catalog.md), generated by booting each tool plugin and harvesting this method (see [the tool-schema-catalog RFC](../../../docs/rfc/implemented/process/2026-07-02-tool-schema-catalog.md)).
 - `ctx.tools.guard(guard: ToolGuard): () => void` Register a monotonic synchronous execution guard after `tools/pre-execute`: returning a reason denies the call, while `undefined` leaves it unchanged. A plain-context guard applies globally; an `agent.ctx` guard applies only to that agent. Later waterfall listeners cannot turn a guard denial back into permission. Disposed with the calling fiber.
-- `ctx.tools.execute(exec: ToolExecutionInput): Promise<ToolExecutionResult>` Assign a fresh opaque correlation token, losslessly materialize and deep-freeze arguments once at the model/tool boundary, then run the call through `tools/pre-execute` → guards → `tools/execute` → `tools/post-execute`. Invalid arguments normalize through the same authoritative result path without reaching policy or the body. The final outcome is independently materialized and deep-frozen once before `tools/result`. Optional `signal` remains the operational field an around-dispatch wrapper may replace.
+- `ctx.tools.execute(exec)` losslessly snapshots and freezes arguments, assigns an opaque token, runs the complete policy/dispatch/result pipeline, then independently snapshots the authoritative outcome before final observation. Invalid arguments use the same result path without reaching policy or the body; around wrappers may replace only `signal`.
 
 ### Injected services
 
@@ -45,7 +45,10 @@ The live registry pipeline has three transformable waterfalls followed by the ob
 ### Extension points
 
 - Tool plugins call `ctx.tools.register()` — schemas flow into the assembly automatically.
-- `tools/pre-execute` is the reorderable allow/deny/ask gate (sandbox, permission, hooks): listeners receive `(exec, next)` and call `next()` to delegate to the default (allow) or return a `PreToolDecision` to short-circuit; a `deny` skips dispatch, while an `ask` resolves through the approval seam and dispatches only after a grant. Either non-grant path yields an `isError` result. `ctx.tools.guard()` installs scope-aware monotonic policy after that waterfall when a denial must not be overridable by listener ordering. `tools/execute` is the around-dispatch seam (timeout, retry, metrics): listeners receive `(exec, next)` and call `next()` to delegate to core dispatch (returning its `ToolExecutionResult`, optionally wrapped), or return a replacement result to short-circuit dispatch; the base `next()` is dispatch-with-normalization, so `await next()` already yields an `isError` result for a thrown or unknown tool. A wrapper may change only `exec.signal` before `next()`—adding a per-call deadline, replacing a caller signal, or restoring absence afterwards—because call identity is protected before policy begins. `tools/post-execute` is the inspect/transform seam: `(exec, result, next)` → a `PostToolDecision` that can replace content, block with feedback, or attach `additionalContext`. Core dispatch is the base of the `tools/execute` waterfall; the tool body keeps its own error boundary so a thrown tool still reaches `post-execute` as an `isError`. Finally, `tools/result` observes the immutable authoritative result after every transform and error boundary. All follow the typed-decision idiom shared with the `agent/*` seams (see [`dsh-agent`](../agent/README.md)); `@deepseek-ai/dsh-timeout-policy` is the reference `tools/execute` wrapper.
+- `tools/pre-execute` is the reorderable allow/deny/ask gate; `ctx.tools.guard()` adds monotonic owner policy after it.
+- `tools/execute` wraps normalized core dispatch for timeout, retry, or metrics. Wrappers may replace only the operational signal.
+- `tools/post-execute` may replace content, block with feedback, or attach context; `tools/result` observes the immutable final outcome.
+- Exact signatures and ordering live in the generated [event catalog](../../../docs/cordis-catalog/events.md) and [pipeline](../../../docs/tool-execution-pipeline.md).
 - MCP servers: one plugin per server, discover tools, call `ctx.tools.register()` with the server's schemas.
 
 ### Typed tool parameter schemas
@@ -77,66 +80,28 @@ ctx.tools.register(defineTool({
 
 The helper converts the author-facing `SchemaSpec` (with `required: true` as a per-property boolean) to standard JSON Schema for the wire format and uses the same typed spec for execute/presentation validation. Raw JSON-Schema tool definitions (from MCP servers) are still accepted by the registry directly.
 
-A `defineTool` tool also **validates the model-generated arguments against its `SchemaSpec` before `execute` runs** (`validateArgs`). The model's JSON is untrusted — `InferArgs<S>` is a compile-time claim, not a runtime guarantee — so on a mismatch (missing required key, wrong primitive, bad enum member, nested violation) the tool throws a `ToolArgsError` (`code: 'INVALID_ARGS'`); the registry turns it into an `isError` result whose text lists the violations, which the model sees and self-corrects from. Validation mirrors the JSON Schema conversion exactly: extra keys are allowed, `default` is not applied, and an `object`/`array` prop without `properties`/`items` only type-checks. Raw-registered tools (MCP) are **not** validated by the harness — they validate their own input.
+A `defineTool` definition validates model arguments before execution and turns missing required values, wrong primitives, invalid enum members, and nested violations into `ToolArgsError` (`INVALID_ARGS`) for the normal error-result path. Extra keys are allowed, defaults are not applied, and object or array fields without `properties` or `items` receive only a type check. Raw-registered tools own their validation.
 
 See `defineTool`, `validateArgs`, `ToolArgsError`, `SchemaSpec`, `InferArgs`, and `schemaSpecToJsonSchema` in the public API for details.
 
-`defineTool` also validates an optional `timeoutMs` at definition time when present: it must be a positive finite number, or the helper throws — the budget is attached to the produced `ToolDefinition` (for `@deepseek-ai/dsh-timeout-policy`) and never reaches the model.
+Optional `timeoutMs` must be positive and finite; it is policy metadata, not model-visible schema.
 
 ### Structured-output schema subset
 
-A separate vocabulary for callers that DEMAND a machine-readable value from an agent — the subagent seam's `SubagentStartRequest.outputSchema` (and, by extension, a workflow's `agent({ schema })`). Unlike `SchemaSpec` (the author-facing DSL for tool parameters), a `StructuredOutputSchema` is an object-rooted **raw JSON Schema subset** as data: it travels verbatim to the model as a forced tool's `parameters`, and the produced value is validated against it.
-
-The subset is deliberately narrow and REJECTS LOUD outside it — accepting a keyword the validator doesn't enforce would validate less than the schema promises (accepted-then-ignored). Supported: single-string `type` (`object`/`array`/`string`/`number`/`integer`/`boolean`/`null`; type arrays rejected), `properties`/`required`/`additionalProperties` (boolean; every `required` key must be declared), `items`, scalar-only `enum`/`const`; annotations (`description`/`title`/`default`/`examples`) are ignored but must still be JSON data. `assertSupportedOutputSchema(schema)` throws `OutputSchemaError` (`code: 'UNSUPPORTED_SCHEMA'`, listing every violation) for anything else; `validateStructuredValue(schema, value)` returns path-qualified violations (empty = valid, total — never throws).
+`StructuredOutputSchema` is the object-rooted raw JSON Schema subset used by subagents and workflows for machine-readable results. It accepts one scalar `type`, object `properties`/`required`/boolean `additionalProperties`, array `items`, and scalar `enum`/`const`. The annotations `description`, `title`, `default`, and `examples` are ignored but must remain JSON data. Type arrays, undeclared required keys, and unsupported keywords fail through `OutputSchemaError` rather than being ignored; `validateStructuredValue()` returns path-qualified violations without throwing.
 
 ### Tool-owned UI presentation
 
-A tool owns how ITS calls render in a UI (an editor's tool-call card, a CLI log line) — a UI plugin must NOT special-case tool names. A `ToolDefinition` may declare two optional, pure, display-only methods that return a **`card`-tagged render intent** (a discriminated union — a tool declares its card kind once and a UI bridge switches on `card`):
+Tools optionally own pure `presentCall()` and `presentResult()` render intents, so UIs do not special-case tool names:
 
-- `presentCall(args): ToolCallView | undefined` — the PENDING state, one of:
-  - `{ card: 'generic', title, kind?, rawInput?, content?, locations? }` — the default card: a human-readable `title`, an optional `kind` (`read`/`edit`/`execute`/… for icon/treatment, default `other`), an optional `rawInput` (the salient input to show in a detail view — e.g. a background task id, NOT the whole args object), optional `content` (extra UI content blocks), and optional `locations` (`{ path, line? }[]` — files this call reads/modifies, so a capable UI can follow along; the ACP bridge forwards them as `tool_call.locations`).
-  - `{ card: 'terminal', title, description?, cwd? }` — a shell command: a capable UI renders a terminal card (the `title` is the command, `description` renders above it, `cwd` heads it); an incapable UI falls back to a generic execute card.
-  - `{ card: 'diff', title, diffs, locations? }` — a file create/modify: a capable UI renders an inline diff card from `diffs` (`{ path, oldText, newText }[]`; `oldText: null` for a new file). Used by `write`/`edit`.
-- `presentResult(args, result): ToolResultView | undefined` — the COMPLETED state, given the same `args` and the `{ content, isError, meta? }` result, one of:
-  - `{ card: 'generic', title?, content? }` — an optional replacement `title` and reformatted `content`.
-  - `{ card: 'terminal', title?, output?, exitCode?, signal? }` — a terminal run's captured `output` and exit status. A capable UI shows an exit-status pill; an incapable UI gets a fenced ` ```console ` fallback the BRIDGE derives from `output` (the tool does not encode the fences).
-  - `{ card: 'diff', title?, diffs }` — a completed file mutation as an inline diff. `diffs` is `FileDiff[]` — typically the applied hunks with surrounding context computed from the before/after content, or a whole-file diff (`oldText: null`) when there is no before-image (a file create). Used by `write`/`edit`; a `tool_call_update.content` replaces the call's content, so a mutation tool returns this even when it duplicates the call-time snippet (else the result text would clobber the pending diff).
+- Call views are `{ card: 'generic', title, kind?, rawInput?, content?, locations? }`, `{ card: 'terminal', title, description?, cwd? }`, or `{ card: 'diff', title, diffs, locations? }`.
+- Result views are `{ card: 'generic', title?, content? }`, `{ card: 'terminal', title?, output?, exitCode?, signal? }`, or `{ card: 'diff', title?, diffs }`.
 
-Returning `undefined` (or omitting a method) tells a UI to fall back to a generic presentation (title = tool name, raw args as input, raw result content). Both methods must be **pure and side-effect-free**: a UI may call them during live streaming AND during a session-log replay, so they depend only on their arguments. `result.meta` is the tool's own optional presentation payload (opaque `unknown`, JSON-serializable), attached by `execute` (see below) and persisted on the `tool/result` event, so a `presentResult` reading it stays replay-deterministic (the same `meta` is read back from the log). With `defineTool`, `args` is the typed `InferArgs<S>` shape; the helper soft-validates before calling (a malformed/older logged arg shape yields `undefined` rather than throwing, since display must never crash a replay). The views are provider-neutral — the ACP bridge (`dsh-acp`) maps each `card` to ACP `tool_call`/`tool_call_update` wire fields (a `diff` card to a `{ type: 'diff' }` content block, a `terminal` card to the `_meta` terminal convention), and relativizes a file card's title against the session cwd. See the render-intent-union RFC (`docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md`) and the applied-hunk-diffs RFC (`docs/rfc/implemented/architecture/2026-07-02-result-time-applied-hunk-diffs.md`); `dsh-tool-bash` (terminal) and `dsh-tool-fs` (diff/generic) are the reference implementations.
-
-```ts
-import { defineTool } from '@deepseek-ai/dsh-tools'
-
-const bash = defineTool({
-  name: 'bash',
-  description: 'Run a shell command.',
-  parameters: {
-    command: { type: 'string', required: true, description: 'The command to run.' },
-    description: { type: 'string', required: true, description: 'One-line summary shown in the UI.' },
-  },
-  async execute(args) {
-    return [{ type: 'text', text: `ran: ${args.command}` }]
-  },
-  // A terminal card: the command is the title, the description renders above it.
-  presentCall: args => ({ card: 'terminal', title: args.command, description: args.description }),
-  // A terminal result: the raw output + exit; the bridge derives the fenced fallback.
-  presentResult: (_args, result) => {
-    const block = result.content.length === 1 ? result.content[0] : undefined
-    if (block === undefined || block.type !== 'text') return undefined
-    return { card: 'terminal', output: block.text }
-  },
-})
-```
+Returning `undefined` selects generic fallback. Presenters depend only on their arguments because UIs call them during live streaming and log replay. Result presentation may read JSON-serializable `result.meta`, which persists with the result; `defineTool` soft-validates older logged arguments and falls back instead of crashing replay. `dsh-tool-bash` and `dsh-tool-fs` are the reference implementations; the [render-intent RFC](../../../docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md) owns the rationale.
 
 ### Code Mode
 
-Under `mode: code` (or `both`) the registry turns the tool surface into a programming API, per the [Code Mode RFC](../../../docs/rfc/implemented/feature/2026-06-15-code-mode.md): the model writes a TypeScript program (the body of an async function) and passes it to the reserved wire transport `run_code`; the program runs in `ctx.codeRuntime` (the [code-execution seam](../../code-runtime/README.md) — the shipped backend is a worker thread) with one async binding per visible end-capability tool (`await tools.bash({...})`), and ONLY what it prints or returns re-enters the model's context. Scope restrictions change those SDK bindings but cannot remove or replace the transport itself.
-
-- **The SDK section** (`tools:sdk`, order 150): a lazy prompt section regenerating, at each assembly, a `declare const tools: {...}` TypeScript declaration of the calling scope's visible end capabilities (exotic names via quoted keys), plus fixed usage instructions. Deterministic — lexicographic tool order, byte-identical text for an unchanged tool set (prefix-cache-friendly). The codegen (`jsonSchemaToTs`, exported) is total: constructs outside the `defineTool` subset degrade to `unknown`, never throw.
-- **The dispatch bridge** (`run_code`'s execute): every binding call is JSON-normalized before dispatch (a value that does not survive — `BigInt`, circulars — rejects that one call, so the dispatched form and logged form are the same JSON value by construction), serialized through a per-run queue (even `Promise.all` executes underlying calls one at a time in submission order), given the outer execution's opaque token as `parent`, and run through the complete pre-execute → guards → execute → post-execute → result pipeline. A denial reaches the program as a binding rejection, and each sub-call is logged as a `tool/code-dispatch` session event with deterministic id `<parent>:code:<n>`; `deriveMessages()` does not surface that event. Token correlation lets commit-style observers defer an inner success until the final `run_code` result without exposing the live outer execution; ordinary tool side effects are not rolled back. A sub-call's `additionalContext` is deliberately dropped because inserting it inside a running parent call would break tool-call/result adjacency.
-- **Settlement discipline**: the bridge owns a run-scoped abort that follows the outer signal in and fires when the run settles for any reason, so a budget expiry aborts an in-flight sub-tool instead of orphaning it; the bridge then drains its queue BEFORE returning, so every `tool/code-dispatch` lands inside the open turn. A failed run throws `CodeRunFailedError` (`code: 'CODE_RUN_FAILED'`, message = the failure kind + captured logs), which the pipeline converts to a structured `isError` the model self-corrects from.
-
-The wire collapse is the registry's own contribution (`systemPrompt.tools()` is mode-aware), so the logged `request/header` records it for free. When no assembly listener changes the registry's prompt or schema contributions, `code` assembles exactly `[run_code]`, pinned by tests and the snapshot goldens. Try it: `pnpm run demo:code-mode` ([the coding-agent example's Code Mode overlay](../../../examples/coding-agent/README.md#code-mode)); `pnpm run demo:code-mode acp` serves the same mode over ACP instead of the REPL.
+Under `code` or `both`, the registry exposes the reserved `run_code` transport and a deterministic TypeScript SDK for the current scope; only program output re-enters model context. Each JSON-normalized binding re-enters the complete tool pipeline sequentially with logged correlation to the outer call. Denials reject that binding, ordinary side effects are not rolled back, and mid-run `additionalContext` is omitted to preserve call/result adjacency. Run settlement aborts and drains outstanding bindings; failures surface as `CodeRunFailedError`. See the [Code Mode RFC](../../../docs/rfc/implemented/feature/2026-06-15-code-mode.md) and [code-runtime seam](../../code-runtime/README.md). Try `pnpm run demo:code-mode`.
 
 ## Model Experience
 

packages/core/tools/src/code-mode.ts

@@ -1,15 +1,7 @@
 /**
- * Code Mode: the `run_code` tool and its dispatch bridge. The model writes a
- * TypeScript program; the bridge hands it to `ctx.codeRuntime` with one async
- * binding per end capability visible to the calling agent, then serializes
- * every binding call through a per-run queue onto `ToolRegistry.execute()`.
- * Sub-calls therefore traverse the complete pre/guard/around/post/final-result
- * pipeline exactly like native calls and carry the outer execution's opaque
- * token for correlation. The bridge logs each sub-dispatch as a
- * `tool/code-dispatch` session event and returns only the program's curated
- * output. The registry itself decides WHEN this tool exists (its `mode`
- * config); this module owns only the tool and the bridge.
- *
+ * Code Mode `run_code` transport. Programs call the registry's agent-visible
+ * tools through nested, sequential executions; each sub-dispatch is logged for
+ * reconstruction, while only the outer curated result enters model history.
  * @module @deepseek-ai/dsh-tools/src/code-mode
  */
 
@@ -24,16 +16,11 @@ import type { ToolDefinition, ToolRegistry } from './index.ts'
 declare module '@deepseek-ai/dsh-session' {
   interface SessionEventMap {
     /**
-     * One bridged sub-dispatch from a `run_code` program: the parent
-     * `run_code` call id, the deterministic sub-call id
-     * (`<parent>:code:<n>`), the tool `name` with its JSON-normalized
-     * `arguments` — the exact value dispatched, normalized BEFORE dispatch,
-     * so this append can never fail on payload shape — whether the sub-call
-     * errored, and a bounded `resultSummary` of its model-facing text.
-     * Log-only: `deriveMessages()` ignores it, so sub-calls never re-enter
-     * model context; persistence and UIs get every call. Appended inside the
-     * parent `run_code`'s execution (the bridge drains its queue before
-     * returning), so the turn-enclosure invariant holds by construction.
+     * One bridged sub-dispatch from a `run_code` program: the parent `run_code` call id, the
+     * deterministic sub-call id (`<parent>:code:<n>`), the tool `name` with its
+     * JSON-normalized `arguments` — the exact value dispatched, normalized before dispatch, so
+     * this append can never fail on payload shape — whether the sub-call errored, and a
+     * bounded `resultSummary` of its model-facing text.
      */
     'tool/code-dispatch': { parentCallId: CallId; subCallId: CallId; name: string; arguments: unknown; isError: boolean; resultSummary: string }
   }
@@ -89,16 +76,11 @@ function summarize(text: string): string {
 }
 
 /**
- * JSON-normalize one binding call's argument into TWO independent parses of
- * the same canonical text: `dispatched` goes to the tool, `logged` to the
- * `tool/code-dispatch` event — identical by construction (the runtime's
- * structured-clone boundary is wider than JSON; the session log accepts only
- * JSON), and separate objects, so a tool mutating its args can neither
- * desync the log from what was dispatched nor re-poison the append. A value
- * that does not survive the round-trip (`undefined` — the log rejects it as
- * event data — `BigInt`, a circular structure, a bare function) rejects that
- * one call BEFORE dispatch with a model-correctable error: nothing ever
- * executes unlogged.
+ * JSON-normalize one binding call's argument into TWO independent parses of the same canonical
+ * text: `dispatched` goes to the tool, `logged` to the `tool/code-dispatch` event — identical
+ * by construction (the runtime's structured-clone boundary is wider than JSON; the session log
+ * accepts only JSON), and separate objects, so a tool mutating its args can neither desync the
+ * log from what was dispatched nor re-poison the append.
  */
 function jsonNormalizeArgs(value: unknown): { dispatched: unknown; logged: unknown } {
   if (value === undefined) {
@@ -139,7 +121,7 @@ function asRunCodeMeta(meta: unknown): RunCodeMeta | undefined {
 
 /**
  * Build the `run_code` {@link ToolDefinition}: one required `code` parameter,
- * executed through the dispatch bridge described in the module doc. The
+ * executed through the dispatch bridge described above. The
  * registry reserves it as presentation infrastructure under non-native modes,
  * outside the filterable global/scoped capability layers.
  * @param registry - the owning registry (sub-calls go through its `execute`,
@@ -172,11 +154,9 @@ export function createRunCodeTool(registry: ToolRegistry, requireRuntime: () =>
       exec.signal?.addEventListener('abort', onOuterAbort, { once: true })
 
       let dispatches = 0
-      // The per-run serialization queue: every binding call chains onto the
-      // tail, so even `Promise.all` executes the underlying tool calls one at
-      // a time in submission order (the tool contract carries no
-      // concurrency-safety metadata yet). The fold keeps the tail non-rejecting
-      // so one failed dispatch never poisons the chain.
+      // The per-run serialization queue: every binding call chains onto the tail, so even
+      // `Promise.all` executes the underlying tool calls one at a time in submission order (the
+      // tool contract carries no concurrency-safety metadata yet).
       let queue: Promise<void> = Promise.resolve()
       const enqueue = <T>(task: () => Promise<T>): Promise<T> => {
         const turn = queue.then(() => {
@@ -211,11 +191,9 @@ export function createRunCodeTool(registry: ToolRegistry, requireRuntime: () =>
             signal: runController.signal,
           })
           const text = textOf(result.content)
-          // Sub-call `additionalContext` is deliberately DROPPED here: the
-          // loop's buffering (append after the step's tool/results) has no
-          // safe analogue from inside a running run_code — injecting now
-          // would break tool-call/result adjacency. Deferred until a real
-          // hook needs it through Code Mode.
+          // Sub-call `additionalContext` is deliberately DROPPED here: the loop's buffering
+          // (append after the step's tool/results) has no safe analogue from inside a running
+          // run_code — injecting now would break tool-call/result adjacency.
           exec.agent?.session.append('tool/code-dispatch', {
             parentCallId: exec.callId,
             subCallId,
@@ -266,18 +244,8 @@ export function createRunCodeTool(registry: ToolRegistry, requireRuntime: () =>
             signal: runController.signal,
           })
         } finally {
-          // Quiescence before returning, whether the runtime fulfilled or
-          // REJECTED (a backend that starts a binding call and then throws
-          // must not leak a live sub-dispatch past this settlement): fire
-          // the run-scoped abort (cancelling an in-flight sub-dispatch,
-          // abandoning queued ones), then await the queue's drain — an
-          // aborted sub-call still settles and logs its event INSIDE the
-          // open turn; nothing can append after we return. `queue` is the
-          // FOLDED tail (every link swallows its rejection into undefined),
-          // so this await cannot itself reject — an abandoned queued call
-          // can never mask the runtime's own failure, returned or thrown;
-          // rejections surface only on the per-call promises the program
-          // holds.
+          // Abort sub-dispatches and drain the folded queue before closing the turn.
+          // Binding failures remain observable through their individual promises.
           runController.abort('run_code settled')
           await queue
         }
@@ -297,13 +265,7 @@ export function createRunCodeTool(registry: ToolRegistry, requireRuntime: () =>
         exec.signal?.removeEventListener('abort', onOuterAbort)
       }
     },
-    // The program IS the title, the way command tools title their cards with
-    // the command: an execute-card's title is the one slot an ACP client
-    // always shows (Zed's execute cards render no body content and no raw
-    // input without a real terminal attached), so anywhere else the code
-    // would be invisible. Multi-line titles are the execute-card idiom —
-    // capable clients render them whole; others truncate to the first line
-    // and still hold the full program in rawInput.
+    // ACP execute cards use the program as their visible title.
     presentCall: args => ({
       card: 'generic',
       title: args.code,

packages/core/tools/src/index.ts

@@ -1,18 +1,6 @@
 /**
- * Tool registry and execution pipeline. Plugins register tools; the registry
- * feeds schemas into the system prompt, and `execute()` dispatches each call
- * through `tools/pre-execute` (the extensible allow/deny gate) → monotonic
- * registered guards → `tools/execute` (an around-dispatch wrapper for
- * timeout/retry/metrics plugins) → `tools/post-execute` (inspect/replace the
- * result, attach context) → the observe-only `tools/result` notification.
- *
- * The registry also owns HOW its tools are presented to the model — its
- * `mode` config: `'native'` (every tool as a wire function definition,
- * today's behavior and the default), `'code'` (the registry's canonical wire
- * contribution is one tool, `run_code`, plus a generated TypeScript SDK prompt section), or
- * `'both'`. See `code-mode.ts` (the tool + dispatch bridge) and
- * `ts-types.ts` (the SDK codegen); design in the Code Mode RFC.
- *
+ * Tool registry, model presentation modes, and pre/guard/around/post/result
+ * execution pipeline.
  * @module @deepseek-ai/dsh-tools
  */
 
@@ -83,79 +71,34 @@ declare module 'cordis' {
 
   interface Events {
     /**
-     * Waterfall BEFORE a tool runs — the gate where sandbox, permission, and
-     * hook plugins allow or deny a call (Claude Code's `PreToolUse`). Listeners
-     * receive `(exec, next)`: call `next()` to delegate to the default (allow),
-     * or return a {@link PreToolDecision} without calling `next()` to
-     * short-circuit. A `deny` skips dispatch and yields an `isError` result; the
-     * tool body never runs. Input rewrite is deliberately NOT offered here (see
-     * {@link PreToolDecision}); `ask` is serviced by the `ctx.approval` seam
-     * when one is mounted, and degrades to deny otherwise.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`) keys the carrier by `exec.agent`: a
-     * listener registered through `agent.ctx` fires only for that agent's
-     * calls, while a plain plugin listener fires for every call (including
-     * agent-less ones, which dispatch subject-less).
+     * Allow, deny, or ask before dispatch. `next()` delegates to allow; missing
+     * approval support turns `ask` into denial.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent's calls.
      * @param exec - the pending call (name, parsed arguments, caller agent).
      * @mode waterfall
      */
     'tools/pre-execute'(this: Scoped<ToolRegistry>, exec: ToolExecution, next: () => Promise<PreToolDecision>): Promise<PreToolDecision>
     /**
-     * Around-dispatch waterfall wrapping the registry's core tool dispatch,
-     * between the `tools/pre-execute` gate and the `tools/post-execute` seam. A
-     * listener receives `(exec, next)`: call `next()` to delegate to dispatch
-     * (returning its {@link ToolExecutionResult}, optionally wrapped), or return a
-     * replacement result without calling `next()` to short-circuit dispatch. The
-     * base `next()` IS the dispatch-with-normalization thunk — a thrown tool (or
-     * unknown tool) is already normalized to an `isError` result by the time a
-     * listener's `await next()` returns, so a wrapper never sees a raw throw from
-     * the tool body. This is the seam a timeout/retry/metrics plugin wraps: it can
-     * set or replace the one mutable field, `exec.signal` (e.g. with a per-call
-     * deadline), BEFORE `next()`, restore/delete it afterward, and inspect the result AFTER. Call identity
-     * (`token`, `callId`, `name`, `arguments`, `agent`, and `parent`) is immutable throughout the
-     * pipeline so a wrapper cannot change which tool and scope the pipeline
-     * accepted. (Cordis `next()` ignores passed arguments and re-invokes
-     * downstream with the shared payload, so a wrapper changes `exec.signal` in
-     * place rather than passing a new object to `next()`.)
-     * Multiple listeners compose by registration order — an outer one wraps the
-     * inner ones plus dispatch.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): the carrier is keyed by
-     * `exec.agent` — a listener registered through `agent.ctx` wraps only that
-     * agent's calls; a plain plugin listener wraps every call (including
-     * agent-less ones, which dispatch subject-less).
+     * Around-dispatch waterfall for timeout, retry, or metrics. `next()` returns
+     * a normalized result; wrappers may change only `exec.signal`, while call
+     * identity remains immutable.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent's calls.
      * @param exec - the allowed call about to dispatch (name, parsed arguments, caller agent, signal).
      * @mode waterfall
      */
     'tools/execute'(this: Scoped<ToolRegistry>, exec: ToolExecution, next: () => Promise<ToolExecutionResult>): Promise<ToolExecutionResult>
     /**
-     * Waterfall AFTER a tool runs — where hook plugins inspect the result and
-     * accept it (optionally REPLACING the model-facing content, and/or attaching
-     * `additionalContext` for the next request) or block it with corrective
-     * `feedback` (Claude Code's `PostToolUse`). Listeners receive
-     * `(exec, result, next)`: call `next()` to delegate to the default (accept
-     * unchanged), or return a {@link PostToolDecision} to override. Core tool
-     * dispatch runs earlier as the base `next()` of the `tools/execute`
-     * waterfall, all inside `execute`'s outer try/catch (and the tool body keeps
-     * its own inner try/catch, so a thrown tool still reaches `post-execute` as an
-     * `isError` result).
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): the carrier is keyed by
-     * `exec.agent` — a listener registered through `agent.ctx` fires only for
-     * that agent's calls; a plain plugin listener fires for every call
-     * (including agent-less ones, which dispatch subject-less).
+     * Accept, replace, enrich, or block a normalized dispatch result. `next()`
+     * accepts it unchanged; thrown tools still reach this seam as errors.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): agent-scoped listeners receive only that agent's calls.
      * @param exec - the call that just ran (name, parsed arguments, caller agent).
      * @param result - the dispatch outcome a listener may accept, replace, or block.
      * @mode waterfall
      */
     'tools/post-execute'(this: Scoped<ToolRegistry>, exec: ToolExecution, result: Readonly<ToolExecutionResult>, next: () => Promise<PostToolDecision>): Promise<PostToolDecision>
     /**
-     * Synchronous notification of the authoritative FINAL tool outcome, after the
-     * complete pre/execute/post pipeline, final lossless-JSON validation, and
-     * outer error normalization.
-     * Unlike the three waterfalls, this seam cannot transform the result: each
-     * listener receives the now-frozen execution object and a deep-frozen result
-     * snapshot; listener failures are contained and logged, and
-     * {@link ToolRegistry.execute} still returns the outcome.
-     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): keyed by
-     * `exec.agent`, using the same carrier as the pipeline.
+     * Observe the frozen, lossless-JSON final outcome. Listener failures are contained.
+     * Scope-filtered dispatch (`@deepseek-ai/dsh-scope`): keyed by `exec.agent`.
      * @param exec - the execution object that traversed the pipeline.
      * @param result - a deep-frozen snapshot of the final returned result.
      * @mode emit
@@ -174,18 +117,10 @@ declare module 'cordis' {
   }
 }
 
-// TODO(review): revisit these shapes when concurrency metadata becomes useful
+// TODO(concurrency): revisit these shapes when concurrency metadata becomes useful
 // (for example, a read-only hint that would permit safe parallel execution).
 
-/**
- * What a tool's `execute` returns. The bare {@link ContentBlock}`[]` form is the
- * common case (model-facing content only); the object form additionally attaches
- * a tool-private `meta` presentation payload that the registry threads onto the
- * `tool/result` session event and hands back to the tool's `presentResult`.
- * `meta` is opaque to the core (`unknown` — the tool owns and narrows its shape),
- * and MUST be JSON-serializable: it persists on the durable log (the session
- * enforces this at `append`), so replay reproduces the card.
- */
+/** Tool output, optionally with lossless-JSON presentation metadata persisted for replay. */
 export type ToolExecuteReturn = ContentBlock[] | { content: ContentBlock[]; meta?: unknown }
 
 /** A registered tool: its schema plus the execution function. */
@@ -236,12 +171,7 @@ export interface ToolResult {
 
 declare const toolExecutionTokenBrand: unique symbol
 
-/**
- * Opaque identity for one trip through the tool pipeline. Nested
- * transports carry the enclosing execution's token instead of its live object,
- * so observe-only result listeners can correlate calls without gaining a
- * mutation path into an outer around-dispatch wrapper.
- */
+/** Opaque call identity that permits correlation without exposing mutable execution state. */
 export type ToolExecutionToken = symbol & { readonly [toolExecutionTokenBrand]: true }
 
 /**
@@ -307,14 +237,8 @@ export interface ToolExecutionResult {
    */
   error?: ToolErrorInfo
   /**
-   * Extra model-facing context a `tools/post-execute` listener attached for the
-   * NEXT request (Claude Code's PostToolUse `additionalContext`). It is NOT part
-   * of this call's `content` — `content`/`feedback` shape the tool RESULT, but
-   * `additionalContext` is a SEPARATE `context/message`. A step can carry
-   * multiple tool calls, so the loop BUFFERS every call's `additionalContext`
-   * and appends them only AFTER all `tool/result`s for the step, keeping
-   * tool-call/result adjacency intact. Carried on the result purely to ferry it
-   * from `execute()` up to the loop's per-step buffer.
+   * Model-facing context for the next request, separate from this tool result.
+   * The loop buffers it until all step results are logged, preserving pairing.
    */
   additionalContext?: HookContext
   /**
@@ -327,19 +251,10 @@ export interface ToolExecutionResult {
 }
 
 /**
- * The decision a `tools/pre-execute` listener returns for one pending call.
- * Maps onto Claude Code's `PreToolUse` `permissionDecision`.
- *
- * - `allow` proceeds to dispatch. (Input rewrite — changing `exec.arguments` —
- *   is deliberately NOT offered: `tool/call` and `assistant/message` are logged
- *   BEFORE execution and live consumers, e.g. the ACP bridge and `dsh-tool-bash`
- *   presentation, read the pre-execution arguments, so an execution-only rewrite
- *   would desync the UI from what RAN. That consistency redesign is its own
- *   `proposed` RFC; `TODO(pre-tool-input-rewrite)` anchors it at the call site.)
- * - `deny` skips dispatch; the loop records an `isError` result carrying `reason`.
- * - `ask` is the permission-prompt intent: serviced as a one-shot decision by
- *   the `ctx.approval` seam when one is mounted (`allowed-once` proceeds to
- *   dispatch; every other outcome denies), degrading to `deny` when none is.
+ * Pre-dispatch decision. `allow` runs the call; `deny` materializes an error;
+ * `ask` runs only after an approval service returns `allowed-once` and otherwise
+ * denies. Input rewriting is excluded because arguments are already logged and
+ * presented.
  */
 export type PreToolDecision =
   | { kind: 'allow' }
@@ -347,16 +262,8 @@ export type PreToolDecision =
   | { kind: 'ask'; reason?: string }
 
 /**
- * The decision a `tools/post-execute` listener returns for one finished call.
- * Maps onto Claude Code's `PostToolUse` decision.
- *
- * - `accept` keeps the call successful; optional `content` REPLACES the
- *   model-facing result (clean: `tool/result` is logged AFTER `execute()`
- *   returns, so a replaced result is the single source of truth for both derived
- *   history and UI). Optional `additionalContext` rides to the next request.
- * - `block` turns the call into an `isError` result whose content is the
- *   corrective `feedback` (the model is told the call was rejected and why),
- *   optionally also attaching `additionalContext`.
+ * Post-dispatch decision: accept or replace content, attach context for the next
+ * request, or block by turning corrective feedback into an error result.
  */
 export type PostToolDecision =
   | { kind: 'accept'; content?: ContentBlock[]; additionalContext?: HookContext }
@@ -399,35 +306,17 @@ export type ToolPresentationMode = 'native' | 'code' | 'both'
 /** Plugin config: how the registered tools are presented to the model. */
 export interface Config {
   /**
-   * The presentation mode. `'native'` (the default) contributes every
-   * visible end capability as a native wire function definition. Under
-   * `'code'` this registry contributes exactly ONE wire tool,
-   * `run_code`, plus the generated `tools:sdk` prompt section declaring every other tool as a
-   * TypeScript API the program calls. `'both'` contributes every native
-   * definition AND `run_code` + the SDK section. Non-native modes require a
-   * loaded `ctx.codeRuntime` whose `language` is `'typescript'` — a missing
-   * or mismatched runtime rejects every prompt assembly with an actionable
-   * error (misconfiguration fails loud, before any model request). A
-   * configured `systemPrompt.toolOrder` naming native tools likewise rejects
-   * every assembly under `'code'` (those names are no longer contributed) —
-   * a deployment switching modes updates its order config or drops it.
+   * Model presentation. `native` (default) sends every visible schema; `code`
+   * sends only `run_code` plus a generated SDK prompt; `both` sends both forms.
+   * Code modes require a TypeScript runtime and fail prompt assembly when it is
+   * absent or mismatched. Under `code`, native names in `toolOrder` are invalid.
    */
   mode?: ToolPresentationMode
 }
 
 /**
- * A per-scope restriction over the GLOBAL tool surface, registered via
- * {@link ToolRegistry.restrict}. `allow` keeps only the listed global tools;
- * `deny` removes the listed ones; both present = allow first, then deny.
- * Restrictions never touch scoped registrations — a tool registered through
- * the same scope is merged after the global filter (which is what keeps e.g. a
- * structured-output capture tool alive under an allow-list). The readonly
- * filter values compile to private sets at registration, but resolution uses the live global registry:
- * a later global name passes a deny-only filter unless explicitly denied and
- * fails an allow-list unless explicitly allowed. The
- * reserved `run_code` presentation transport is likewise outside capability
- * filtering, and naming it explicitly is rejected. Multiple restrictions on
- * one scope compose by intersection: every one must admit.
+ * Per-scope filter over global tools. Restrictions intersect and do not affect
+ * scoped registrations or the reserved Code Mode transport.
  */
 export interface ToolRestriction {
   /** Global tool names that stay visible; everything else is removed. */
@@ -468,26 +357,8 @@ interface ToolGuardRegistration {
 }
 
 /**
- * Tool registry (`ctx.tools`): tool plugins register definitions; the agent
- * loop executes calls through the `tools/pre-execute` → guards →
- * `tools/execute` → `tools/post-execute` → `tools/result` pipeline. The
- * registry contributes its schemas into the system-prompt assembly — WHICH
- * schemas is governed by its `mode` config
- * (see {@link Config.mode}); under a non-native mode it also owns the reserved
- * `run_code` presentation transport and the `tools:sdk` prompt section.
- *
- * Two registration layers (`@deepseek-ai/dsh-scope`): a registration through a
- * plain plugin context is GLOBAL (visible to every agent); one through a
- * scoped context (`agent.ctx`) is filed in that scope's layer — visible to
- * that agent alone, disposed with the scope, and SHADOWING a global tool of
- * the same name for that agent (most-specific-wins; within one layer a
- * duplicate name still throws). {@link restrict} masks the global layer per
- * scope. One private visibility resolver feeds the registry's prompt
- * contribution, {@link get}, and {@link execute} — and, under a non-native
- * mode, the SDK section and `run_code`'s bindings — so those registry-owned
- * presentation and dispatch paths agree. An expert `system-prompt/assemble`
- * listener may deliberately replace the final wire composition and owns any
- * resulting divergence.
+ * Tool registry and execution pipeline. Scoped registrations shadow globals;
+ * one visibility resolver feeds presentation, lookup, and dispatch.
  */
 export class ToolRegistry extends Service {
   static inject = ['systemPrompt']
@@ -525,13 +396,7 @@ export class ToolRegistry extends Service {
       ctx.systemPrompt.section({
         name: 'tools:sdk',
         order: SDK_SECTION_ORDER,
-        // A lazy thunk over the live registry, per assembly CONTEXT:
-        // regenerated at each assembly over the CALLING SCOPE's visible set
-        // (scoped tools join, restricted globals vanish — the SDK declares
-        // exactly what that agent's programs can call), in lexicographic
-        // tool order, so an unchanged tool set renders byte-identical text
-        // (prefix-cache-friendly) and a mid-session registration surfaces
-        // exactly like a native-mode tool change.
+        // Regenerate from the calling scope's visible tools in stable order.
         text: (context) => {
           this.requireCodeRuntime()
           return renderToolsSdk(this.schemas(context.scope).filter(schema => schema.name !== RUN_CODE_NAME))
@@ -541,22 +406,8 @@ export class ToolRegistry extends Service {
   }
 
   /**
-   * The registry's contribution to the wire tool list, per {@link Config.mode},
-   * as ONE SCOPE sees it (scoped layer joins, shadowing and restrictions
-   * applied — {@link schemas}). Because `PromptAssembly.tools` is what the
-   * loop's request header snapshots, the mode's collapse is logged and
-   * reconstructable for free. Under a non-native mode this is also the loud
-   * misconfiguration gate: no usable code runtime → every assembly rejects
-   * before any model request.
-   *
-   * The `knownNames` universe distinguishes the two ways a tool can be off
-   * the wire: a per-scope RESTRICTION is runtime state, so `knownNames` stays
-   * pre-restriction and a restricted-away tool in `toolOrder` is a normal
-   * absence — while the MODE collapse is deployment config, so under
-   * `mode: 'code'` the universe is `[run_code]` and a `toolOrder` naming a
-   * native tool is dead configuration that fails every assembly loud. Under
-   * `mode: 'both'`, the provider adds the reserved transport to the
-   * capability-only known-name universe for `toolOrder` validation.
+   * Build one scope's wire schemas and names for prompt-order validation.
+   * Restrictions do not make known tools invalid, but a mode collapse does.
    */
   private wireSchemas(scope?: ScopeKey): ToolProviderResult {
     const view = this.view(scope)
@@ -594,23 +445,10 @@ export class ToolRegistry extends Service {
   }
 
   /**
-   * Register a tool. The layer is decided by the CALLING context: a plain
-   * plugin context registers globally; a scoped context (`agent.ctx`)
-   * registers into that scope's layer — visible to that agent alone, disposed
-   * with the scope, and shadowing a same-named global tool for that agent.
-   * Throws if the SAME layer already has the name (cross-layer name twins are
-   * the shadowing feature, not an error; the global-duplicate message names
-   * `agent.ctx` as the per-agent alternative), or if a non-native mode reserves
-   * the `run_code` name for its presentation transport. The visible schema set
-   * flows into prompt assembly automatically. Definitions are trusted typed
-   * same-process contributions; JSON materialization happens when the schema or
-   * result reaches its model/log boundary. Emits `tools/change` on
-   * register/unregister.
-   * @param definition - the tool's schema plus its execute (and optional
-   *   presentation) functions.
-   * @returns the disposer that unregisters the tool. The exact
-   *   Cordis effect disposer (single-shot): composite (generator) effects may
-   *   yield it directly — exact identity nests the teardown in order.
+   * Register globally or in the calling agent scope. Scoped tools shadow
+   * globals; duplicates within one layer and the reserved `run_code` name fail.
+   * @param definition - the tool schema, execution, and optional presentation functions.
+   * @returns the exact disposer that unregisters the tool.
    */
   register(definition: ToolDefinition): () => void {
     const scope = scopeOf(this.ctx)
@@ -631,52 +469,26 @@ export class ToolRegistry extends Service {
           : `tool "${name}" is already registered in this scope`)
       }
       layer.set(name, definition)
-      // Yield the rollback BEFORE emitting `tools/change`: a generator effect
-      // collects each yielded disposer before the next step runs, so a throwing
-      // `tools/change` listener removes the tool instead of leaking it (a leak
-      // would wedge the duplicate-name check until restart). The duplicate
-      // throw above fires before any mutation — it leaks nothing.
+      // Install rollback before notifying listeners.
       yield () => {
         layer.delete(name)
-        // An emptied scope layer is dropped so a disposed scope leaves no
-        // residue keyed by its (dead) key.
+        // Drop empty scope layers.
         if (scope !== undefined && layer.size === 0) this.scoped.delete(scope)
         this.ctx.emit('tools/change')
       }
       this.ctx.emit('tools/change')
     }.bind(this), 'tools.register()')
-    // The EXACT cordis effect disposer, not a wrapper: a composite (generator)
-    // effect that owns a teardown ORDER must be able to yield THIS function —
-    // cordis nests a disposer out of the fiber's concurrent sibling list by
-    // exact function identity, so a wrapper would silently break the nesting
-    // (the agents.register() lesson). Cleanup is synchronous because this
-    // registration installs only synchronous state and notifications.
+    // Return the exact disposer so composite effects preserve teardown order.
     // eslint-disable-next-line @typescript-eslint/no-misused-promises -- synchronous cleanup; direct return preserves disposer identity
     return dispose
   }
 
   /**
-   * Restrict the GLOBAL tool surface for the calling scope. Must be called
-   * through a scoped context (`agent.ctx`) — restricting "everyone" is not a
-   * thing (throw), and an empty filter (neither `allow` nor `deny`) is a no-op
-   * that can only be a bug (throw — the materialized-empty-config trap).
-   * Validates every listed name against the CURRENT global end-capability
-   * universe and throws on an unknown or scope-local name (fail loud
-   * beats a typo silently filtering nothing) — register restrictions after the
-   * global tools they mask exist (the agent-creation `setup` window satisfies
-   * this). A non-native mode's reserved `run_code` presentation transport is
-   * not a filterable capability; naming it explicitly throws, while omitting
-   * it from an allow-list cannot remove it. The readonly arrays are compiled to
-   * private sets at registration. Resolution still uses the live global registry, so a later
-   * global name passes a deny-only filter unless named and fails an allow-list
-   * unless named. Multiple restrictions compose by intersection. Scoped
-   * registrations are merged after restrictions and therefore remain visible.
-   * Disposed with the calling fiber (revocable independently); emits
-   * `tools/change`.
+   * Restrict global tools for the calling agent scope. Empty filters, unknown
+   * names, scope-local names, and reserved transport names fail. Restrictions
+   * intersect; scoped registrations remain visible.
    * @param filter - global-surface mask: `allow` (keep only) and/or `deny` (remove).
-   * @returns the disposer that lifts this restriction. The exact
-   *   Cordis effect disposer (single-shot): composite (generator) effects may
-   *   yield it directly — exact identity nests the teardown in order.
+   * @returns the exact disposer that lifts this restriction.
    */
   restrict(filter: ToolRestriction): () => void {
     const scope = scopeOf(this.ctx)
@@ -714,12 +526,7 @@ export class ToolRegistry extends Service {
       }
       this.ctx.emit('tools/change')
     }.bind(this), 'tools.restrict()')
-    // The EXACT cordis effect disposer, not a wrapper: a composite (generator)
-    // effect that owns a teardown ORDER must be able to yield THIS function —
-    // cordis nests a disposer out of the fiber's concurrent sibling list by
-    // exact function identity, so a wrapper would silently break the nesting
-    // (the agents.register() lesson). Cleanup is synchronous because this
-    // registration installs only synchronous state and notifications.
+    // Return the exact disposer so composite effects preserve teardown order.
     // eslint-disable-next-line @typescript-eslint/no-misused-promises -- synchronous cleanup; direct return preserves disposer identity
     return dispose
   }
@@ -841,15 +648,8 @@ export class ToolRegistry extends Service {
   }
 
   /**
-   * The model-facing schemas of everything `scope` can see — exactly the
-   * fields (`name`, `description`, `parameters`) this registry contributes to
-   * system-prompt assembly before its expert transformation waterfall.
-   * Constructed EXPLICITLY rather than by stripping
-   * known non-schema members: a `ToolDefinition` also carries `execute` and the
-   * optional `presentCall`/`presentResult` UI callbacks, and those (especially
-   * the functions) must never leak into a model request. An allowlist can't
-   * drift when a new non-schema member is added to the definition; a denylist
-   * (rest-destructure) would silently leak it.
+   * Project visible definitions onto the allowlisted model-facing schema fields,
+   * excluding execution and presentation callbacks.
    * @param scope - the viewing scope (the agent); omitted = the global view.
    * @returns one deep-cloned schema per visible tool.
    */
@@ -868,27 +668,13 @@ export class ToolRegistry extends Service {
   }
 
   /**
-   * Execute one tool call through the `tools/pre-execute` → guards →
-   * `tools/execute` (around dispatch) → `tools/post-execute` → `tools/result`
-   * pipeline. `pre-execute` is the extensible gate
-   * (allow/deny/ask), `tools/execute` wraps core dispatch (a timeout/retry/metrics
-   * seam), and `post-execute` is the inspect/transform seam; core dispatch sits
-   * as the base `next()` of the `tools/execute` waterfall. The whole thing is
-   * wrapped in one outer try/catch so a throwing listener (in any waterfall)
-   * becomes an `isError` result instead of failing the turn; the tool body ALSO
-   * keeps its own inner try/catch, so a thrown tool becomes an `isError` result
-   * that `tools/execute` and `post-execute` listeners can still inspect. If the
-   * tool is not registered (or not visible to the calling agent — a
-   * restricted-away global is exactly as absent as a nonexistent one), the
-   * result is an `isError` carrying a `UNKNOWN_TOOL` structured error. A thrown
-   * {@link HarnessError} surfaces its `{ name, code }` on the result. Before
-   * the final observe-only notification, the authoritative outcome is
-   * materialized as a detached lossless-JSON snapshot; an invalid outcome is
-   * normalized to an error.
+   * Execute through pre-policy, guards, around-dispatch, post-policy, and final
+   * notification. Tool and listener failures resolve as materialized error
+   * results; an invisible tool reports `UNKNOWN_TOOL`. The returned outcome is
+   * the same lossless, frozen snapshot final observers receive.
    * @param exec - the typed same-process call input. The registry assigns its
    *   correlation token before policy begins.
-   * @returns the materialized final result after every waterfall; listener and
-   *   tool failures resolve as `isError` results rather than rejections.
+   * @returns the materialized final result.
    */
   async execute(exec: ToolExecutionInput): Promise<ToolExecutionResult> {
     const token = createExecutionToken()

packages/core/tools/src/json-schema.ts

@@ -1,31 +1,9 @@
 /**
- * Structured-output JSON Schema subset: the vocabulary a caller uses to demand
- * a machine-readable result from a subagent (`SubagentStartRequest.outputSchema`)
- * or a workflow `agent()` call.
- *
- * This is deliberately NOT full JSON Schema. The schema travels verbatim to the
- * model as a forced tool's `parameters`, and the value the model produces is
- * validated here — so every accepted keyword must be one this module actually
- * enforces. Accepting a keyword we don't enforce would validate less than the
- * schema promises (accepted-then-ignored), so anything outside the subset is
- * REJECTED LOUD by {@link assertSupportedOutputSchema} instead. The subset:
- *
- * - `type` — a single string (`object`/`array`/`string`/`number`/`integer`/
- *   `boolean`/`null`); type ARRAYS (`["string","null"]`) are rejected.
- * - `properties`/`required`/`additionalProperties` (boolean) on objects; every
- *   `required` key must be declared in `properties`. `additionalProperties`
- *   absent keeps standard JSON Schema semantics (extra keys allowed).
- * - `items` on arrays (absent ⇒ any JSON items).
- * - `enum` (non-empty, scalars only) and `const` (scalar) on scalar types.
- * - Annotations `description`/`title`/`default`/`examples` are allowed and
- *   ignored (they constrain nothing), except that they must still be JSON data
- *   — the schema is serialized onto the wire, so a non-JSON annotation would be
- *   silently mangled.
- *
- * Values checked by {@link validateStructuredValue} are expected to be plain
- * host-realm JSON data (model tool-call arguments are parsed wire JSON; a
- * caller holding foreign-realm data materializes it first).
- *
+ * Structured-output JSON Schema subset for subagents and workflows. It supports
+ * one scalar `type`; object `properties`/`required`/boolean
+ * `additionalProperties`; array `items`; scalar `enum`/`const`; and JSON-valued
+ * annotations. Unsupported or misplaced keywords reject rather than being
+ * accepted without enforcement, and structured-output roots must be objects.
  * @module dsh-tools/json-schema
  */
 

packages/core/tools/src/presentation.ts

@@ -1,20 +1,7 @@
 /**
  * Tool render-intent vocabulary: the provider-neutral types a tool declares via
- * `ToolDefinition.presentCall`/`ToolDefinition.presentResult` to say
- * how ONE of its calls renders in a UI (an editor's tool-call card, a CLI log
- * line). A UI bridge switches on the `card` tag to map each intent to its own
- * wire shape, so a UI never special-cases tool names.
- *
- * This is the UI-facing surface of `dsh-tools`, kept separate from the registry
- * and execution core in `index.ts`: this module owns ONLY presentation
- * vocabulary and references none of the execution types, so the dependency runs
- * one way (`index.ts` imports these views for the `ToolDefinition` method
- * signatures). The opaque `meta` presentation channel is execution plumbing and
- * lives with the registry in `index.ts`, not here.
- *
- * See the render-intent-union RFC
- * (docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md).
- *
+ * `ToolDefinition.presentCall`/`ToolDefinition.presentResult` to say how one of its calls
+ * renders in a UI (an editor's tool-call card, a CLI log line).
  * @module @deepseek-ai/dsh-tools/src/presentation
  */
 
@@ -56,14 +43,8 @@ export interface FileDiff {
 }
 
 /**
- * How a tool wants ONE of its calls shown in a UI (an editor's tool-call card, a
- * CLI log line) BEFORE the result is known — the *pending* state. A `card`-tagged
- * discriminated union: a tool declares its render INTENT once and a UI bridge
- * switches on `card` to map it to the bridge's own wire shape. Provider-neutral —
- * the tool owns its presentation, so a UI never special-cases tool names.
- *
- * Returned by `ToolDefinition.presentCall`. See the render-intent-union
- * RFC (docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md).
+ * Provider-neutral pending-call presentation. Tools declare one tagged intent;
+ * UI bridges map it without special-casing tool names.
  */
 export type ToolCallView = GenericCallView | TerminalCallView | DiffCallView
 
@@ -186,16 +167,10 @@ export interface TerminalResultView {
 }
 
 /**
- * A completed file mutation rendered as an inline diff card, the *result-time*
- * analogue of {@link DiffCallView}. Set by a tool whose `execute` applied a file
- * change (e.g. `write`, `edit`): `diffs` are the change to show — typically the
- * APPLIED hunks computed from the before/after content (one entry per hunk, each
- * with surrounding context lines), so the editor shows the real change in place;
- * a tool with no before-image (e.g. a file create) may instead give a whole-file
- * diff (`oldText: null`). A `tool_call_update`'s content REPLACES the call's
- * content in an editor, so a mutation tool returns this even when it duplicates
- * the call-time snippet — otherwise the model-facing result text would replace
- * (clobber) the pending diff card.
+ * A completed file mutation rendered as an inline diff card, the result-time
+ * analogue of {@link DiffCallView}. Because a completed UI update replaces the
+ * pending card content, mutation tools return this even when it repeats the
+ * call-time diff; otherwise raw result text would replace the diff.
  */
 export interface DiffResultView {
   card: 'diff'

packages/core/tools/src/schema.ts

@@ -1,23 +1,4 @@
-/**
- * Typed tool-parameter schema DSL.
- *
- * Plugin authors write per-property specs with `required: true` as a boolean
- * (the `SchemaSpec` type). A type-level helper (`InferArgs`) maps a SchemaSpec
- * to the TS argument type. At runtime, `schemaSpecToJsonSchema()` converts a
- * SchemaSpec to standard JSON Schema (`type: 'object'`, `properties`,
- * `required` array) for the wire format sent to the model.
- *
- * # Why a custom DSL and not schemastery?
- *
- * Schemastery is a validation/transformation library (StandardSchema v1) used
- * for plugin Config. Tool parameters need JSON Schema specifically (the LLM
- * wire format), not validation. A lightweight DSL focused on JSON Schema
- * generation, with type inference for the tool's `execute` args, gives plugin
- * authors the best DX with the smallest surface area. Schemastery would add
- * unnecessary indirection and wouldn't cleanly produce JSON Schema.
- *
- * @module dsh-tools/schema
- */
+/** Typed tool-parameter DSL with argument inference and JSON Schema output. @module dsh-tools/schema */
 
 import { assertNever, HarnessError } from '@deepseek-ai/dsh-llm'
 import type { ToolDefinition, ToolExecuteReturn, ToolExecution, ToolResult } from './index.ts'
@@ -328,39 +309,13 @@ export interface DefineToolOptions<S extends SchemaSpec> {
 }
 
 /**
- * Define a tool with a typed parameter schema.
- *
- * Use this instead of constructing a raw {@link ToolDefinition} for all
- * first-party tools. The `parameters` use the boolean-required style
- * (`required: true` as a per-property flag), and `execute` receives typed
- * args derived from the schema.
- *
- * ```ts
- * const tool = defineTool({
- *   name: 'read_file',
- *   description: 'Read a file from disk.',
- *   parameters: {
- *     path: { type: 'string', required: true, description: 'Absolute file path' },
- *     offset: { type: 'number' },
- *     limit: { type: 'number', description: 'Max lines to read' },
- *   },
- *   async execute(args) {
- *     // args: { path: string; offset?: number; limit?: number }
- *   },
- * })
- * ```
- *
- * Raw JSON-Schema tool definitions (from MCP servers) are still accepted
- * by `ToolRegistry.register()` directly — `defineTool` is sugar for
- * first-party plugin authors.
- *
+ * Define a first-party tool whose execution and presentation arguments are
+ * inferred from its per-property schema. Raw JSON-Schema definitions remain
+ * valid inputs to {@link ToolRegistry.register}; this helper is authoring sugar.
  * @param options - the tool's name, description, typed parameter schema,
  *   execute body, and optional presenters.
- * @returns a registry-ready {@link ToolDefinition}: its `execute` validates the
- *   raw args first (throwing {@link ToolArgsError} on mismatch, which the
- *   registry turns into an isError result), and its presenters validate softly
- *   (returning undefined on mismatch, since replay may feed them older-schema
- *   args).
+ * @returns a registry-ready definition with strict execution validation and
+ *   soft presenter validation for replay compatibility.
  */
 export function defineTool<S extends SchemaSpec>(options: DefineToolOptions<S>): ToolDefinition {
   // Object-literal execute methods don't use `this`; the reference is safe.

packages/core/tools/src/ts-types.ts

@@ -1,17 +1,8 @@
 /**
- * Code Mode codegen: the pure projection from registered tool schemas to the
- * TypeScript SDK text the model programs against (the `tools:sdk` prompt
- * section). Sibling of `json-schema.ts` — `schemas()` (native function
- * calling) and this module (the generated `declare const tools` surface) are
- * two projections of the same store.
- *
- * TOTAL by design: {@link jsonSchemaToTs} maps the JSON-Schema subset the
- * `defineTool` DSL emits and degrades every construct outside it (`$ref`,
- * `oneOf`, `integer`, future MCP shapes, …) to `unknown` without ever
- * throwing — codegen must never be the thing that fails an assembly.
- * Deterministic: a fixed tool set renders byte-identical text (tools in
- * lexicographic name order), so the section is prefix-cache-friendly.
- *
+ * Code Mode codegen: the pure projection from registered tool schemas to the TypeScript SDK
+ * text the model programs against (the `tools:sdk` prompt section). Sibling of
+ * `json-schema.ts` — `schemas()` (native function calling) and this module (the generated
+ * `declare const tools` surface) are two projections of the same store.
  * @module @deepseek-ai/dsh-tools/src/ts-types
  */
 
@@ -33,10 +24,8 @@ function pad(indent: number): string {
 /** A one-line JSDoc block for a schema `description`, or no lines when there is none. */
 function docLines(description: unknown, indent: number): string[] {
   if (typeof description !== 'string' || description.length === 0) return []
-  // Keep the doc a single-line comment per property: descriptions are prose
-  // (possibly with newlines); collapse whitespace so the rendered SDK stays
-  // stable and compact. A comment-closer inside the description is escaped so
-  // it cannot terminate the generated JSDoc early.
+  // Collapse prose to stable one-line docs and escape comment closers so a
+  // schema description cannot terminate generated JSDoc.
   const collapsed = description.replace(/\s+/g, ' ').trim()
   return [`${pad(indent)}/** ${collapsed.replaceAll('*/', String.raw`*\/`)} */`]
 }