Extend SandboxMode enforcement from bash to the filesystem tools, the sandbox
RFC's deferred cross-family phase.
- dsh-sandbox-policy (new, ctx.sandboxPolicy): the single home for the
deployment default mode + workspaceRoot and the per-session override event,
renamed bash/sandbox-mode -> sandbox/mode and moved here with its fold/setter.
Decouples the bash seam from dsh-session.
- dsh-fs-sandbox (new): SandboxedFileSystem extends LocalFileSystem and fences
write/edit by the per-call mode (read-only denies, workspace-write contains to
the workspace + temp roots via the shared writableRoots, danger passes
through); reads pass through. Structured FS_SANDBOX_DENIED; in-lock parent
re-canonicalization. A policy fence in trusted code, not a kernel boundary.
- dsh-sandbox: the shared escalation kit (writableRoots, the strictly-wider
ladder, denial/hint markers, approveEscalation) both tool families use;
approveEscalation takes a structural approver so dsh-sandbox gains no
approval/agent dependency, and both tools stay duplication-free.
- tool-fs: write/edit advertise sandbox_permissions/justification under a
confining ctx.fs, map FS_SANDBOX_DENIED to the shared [sandbox: ...] marker,
and resolve the same one-approved-wider retry.
- examples/acp-agent: composes sandbox-policy + fs-sandbox, drops the gating
that disabled the fs stack under confined modes.
RFC docs/rfc/implemented/feature/2026-07-14-cross-family-fs-sandbox.md; the old
sandbox RFC's In-process/deferred/FAQ sections updated to shipped fact.
Review round 2 (tianyicui inline comments):
- dsh-system-prompt itself registers the harness:identity (-100) and
deployment:persona (0) sections — they must survive a swapped loop
plugin, so they leave dsh-agent-loop; the persona text is the plugin's
own validated 'persona' config. The model/cwd variables STAY on the
loop: runtime facts of the agents it drives.
- AgentOptions.systemPrompt is deleted with all its forwarding plumbing:
the app configs' systemPrompt keys become 'persona' routed through
dsh-agent-core (schema = z.intersect of the owners'), the ACP bridge
and tool-subagent stop carrying persona configuration, and subagent
children now render the deployment persona like every other agent.
- Example personas drop transport/interface trivia (ACP, CLI) — facts
irrelevant to the model.
- Root CONTEXT.md removed (not idiomatic); its persona definition was
wrong under the new ownership anyway.
- Docs, READMEs, the prompt-variables RFC, and generated catalogs
updated; new loop test pins the assemble-waterfall escape valve
(an emptied assembly sends NO system field).
A Codex review pass on the draft caught four real gaps and two solid
suggestions; all addressed except one pushed back on the merits:
- hooks-claude/hooks-codex: stderrSummaryMaxChars was the one new knob
with NO range validation — a negative/NaN cap would silently
misbehave inside slice(). Both bridges now assert a positive integer
at the TOP of apply() (before the config-file parse's early return,
so a bad value fails the load loudly), with rejection tests.
- tool-fs: the read caps count lines/chars/bytes, so positive-FINITE
was too loose (a fractional readLimit would flow into windowing
arithmetic and the schema description). All four now require a
positive integer, matching tool-web's cap.
- Doc drift the gates cannot catch: tool-web's README tools table
still named WEB_SEARCH_MAX_RESULTS as the mechanism; compact-basic's
README/module doc and the compaction-capability-seam RFC still
described estimation as fixed char/4 rather than the charsPerToken
default.
- subagent-acp: the dispose graces were tested only at the
startAcpRun level, so a regression that stopped threading plugin
config into AcpRunSpec would have survived. A provider-path test now
drives the trap-escalation scenario through ctx.subagents.start with
small config graces and bounds dispose at 4s.
Pushed back on: converting compact-basic's charsPerToken to a
schemastery field. The package's whole config is deliberately
hand-rolled (resolveConfig, every threshold REQUIRED with no default —
a documented design posture); one schemastery field beside it would be
incoherent. The knob is cordis.yml-reachable, defaulted, and validated,
which is what the convention requires; migrating the package to
schemastery wholesale is pre-existing config-surface hygiene out of
this change's scope.
The audit swept every packages/*/* plugin for the new AGENTS.md
convention (no hardcoded tunables in plugins) and exposes each finding
as a defaulted, validated Config field. Defaults are the previously
hardcoded values throughout, so no deployment or golden changes.
- tool-fs (had NO Config): readLimit, readMaxLineLength, readMaxBytes,
readStreamMinSize. The caps thread through ReadToolCaps/ReadWindow —
read-render already documented that the consumer applies the caps, so
they become explicit per-request fields.
- tool-web: searchMaxResults (WEB_SEARCH_MAX_RESULTS stays as the
schemastery default). Also fixes the stale GREP_LIMIT references in
search.ts and the web-capability-seam RFC (no such constant exists).
- bash-local: graceMs (SIGTERM->SIGKILL escalation grace). The
RunInternals.graceMs test seam is gone: graceMs is now a required
SpawnSpec field filled from config, so tests exercise the real
config path and the defaults live in exactly one place.
- subagent-acp: disposeEofGraceMs / disposeGraceMs. The AcpRunSpec
fields become required for the same one-defaulting-layer reason.
- session-persistence-sqlite: journalMode ('wal' default; the
rollback-journal modes serve filesystems where WAL's shared-memory
files do not work, e.g. network mounts).
- hooks-claude + hooks-codex: stderrSummaryMaxChars for the persisted
hook/result stderr summary. The duplicated summarize() helpers merge
into hook-protocol's summarizeStderr(stderr, maxChars), beside the
HookResultRecord field it feeds, with the bound parameterized the
same way runHook's defaultTimeoutMs already is.
- compact-basic: charsPerToken for the token estimator (default 4, the
English-text heuristic; CJK-heavy deployments need ~1-2 or compaction
fires far too late). Also corrects the BasicCompactService class doc,
which claimed defaults the required-field config never had.
- fs-local: deletes the dead STREAM_MIN_SIZE constant and the dead
FsIoInternals.streamMinSize seam — the read-routing bound lives in
the consumer (tool-fs), where it is now config. This is item 1 of
the proposed prune-write-only-fs-surface RFC, annotated accordingly.
Every new field gets range validation (following the existing
assertPositiveFinite pattern), a README row, and tests covering the
configured behavior, the schema default, and load-time rejection.
The fs seam split left four pieces of pre-split surface populated on
every call and read by nobody:
- STREAM_MIN_SIZE + FsIoInternals.streamMinSize in dsh-fs-local: the
backend has no read routing (readWholeText/streamWholeText are
separate primitives the caller picks), and the real 10 MiB routing
constant lives in dsh-tool-fs's read tool. Delete the dead mirror and
the knob whose JSDoc claimed an override that did not exist; the
remaining FsIoInternals knobs stay (the atomic-write tests use them).
- FsTarget.inputPath: a "diagnostics only" field every backend and test
fake had to fabricate, with zero production readers (policy and error
messages use targetKey/displayPath). listDir gave children the bare
entry name, which was nobody's input.
- FsEditOutcome.replacements/.replaceAll: replacements had no reader
(the single-match policy is enforced by the FS_AMBIGUOUS_EDIT /
FS_EDIT_NOT_FOUND throws, whose message keeps the internal count);
replaceAll only echoed the replace_all argument back to
formatEditOutput, which now takes it from the parsed args. The
outcome shrinks to { version, before, after }, parallel to
FsWriteOutcome's backend-discovered fields. Emitted text is unchanged
for both branches (no snapshot churn).
- FileReadOutcome.limit/.version: formatReadOutput renders
offset/lines/totalLines/truncatedByBytes only, and the fs/observed
emit uses info.version directly.
Backends shed four fabrication obligations and gain none. Doc pastes
(core-data-structures/filesystem.md), the dsh-fs README resolve row,
and the test fakes shrink with the types. RFC moved to
implemented/simplification and amended to the shipped shape
(FsEditSpec -> FsEditRequest name fix; manifest rows needed no change).
A Write CREATE rendered its completed tool_call_update as the model-facing
result TEXT (`<path>…</path>…Created file`), which — because an ACP
tool_call_update.content REPLACES the call's content — clobbered the
new-file diff the pending call installed. So Zed showed the diff, then
replaced it with raw XML-ish text; only overwrite/edit looked right
(their result re-sends a diff).
write's presentResult now ALWAYS returns a diff card for a successful
write: the applied contextual hunk from `meta` when there is one
(overwrite), else an args-derived whole-file diff (`oldText: null`) for a
create or an unchanged-content overwrite. This matches claude-agent-acp,
where the create diff rides on the update and no result text replaces it.
An error still falls through to generic rendering so its message shows.
edit is unchanged (it always has a hunk; no whole-file fallback).
Re-recorded fs-write / fs-write-overwrite goldens; the create's completed
update is now a {type:'diff'} block, not the XML result text.
fs write/edit now emit a result-time contextual-diff tool_call_update
(the applied hunk with ±3 context lines, one hunk per replace_all site),
matching what claude-agent-acp sends and what makes an editor render the
change in place. The call-time snippet diff stays; the result hunk
supersedes it (ACP content-replace).
Mechanism:
- A persisted tool-private `meta` channel: execute may return
`{ content, meta }`; `meta` (JsonValue) rides on the tool/result event
and is handed back to presentResult, so the diff reproduces on replay
(event-sourced). JsonValue is now exported from dsh-session.
- The backend returns raw before/after text (storage facts) on
FsWriteOutcome/FsEditOutcome; the tool computes the hunk via the npm
`diff` package's structuredPatch. A create has no before → no result
diff; a failed/aborted mutation carries no meta.
- ToolResultView gains a DiffResultView; the bridge's result-side switch
renders it as {type:'diff'} content blocks.
RFC: docs/rfc/implemented/architecture/2026-07-02-result-time-applied-hunk-diffs.md
(justifies the npm `diff` runtime dep over vendoring and the meta channel);
the render-intent-union RFC's Non-goal is updated to record this shipped.
All fs snapshot goldens re-recorded; edit/overwrite gain the contextual
result diff, create/read/policy-reject unchanged in structure.
Replace the "bag of optional fields" tool-presentation types
(ToolCallPresentation / ToolResultPresentation / ToolTerminal) with a
card-tagged discriminated union — the standing FIXME(tool-presentation).
A tool declares one render intent per call/result and the ACP bridge
switches on `card`:
ToolCallView = generic | terminal | diff
ToolResultView = generic | terminal
The `diff` card is new: fs write/edit now emit an ACP {type:'diff'}
content block (an editor's inline diff), which the old shapes could not
express. The bridge also relativizes a file card's title against the
session cwd (mirroring claude-agent-acp's toDisplayPath) while keeping
locations/diff paths raw, and derives the no-capability fenced console
fallback from a terminal result's output. read gains the window-in-title
(`Read foo.txt (5 - 8)`) and an always-set location line, matching the
reference adapter field-for-field.
Migrates all three producer families (tool-fs, tool-bash, tool-todo) and
the sole consumer (the ACP bridge) together — the source does not compile
piecewise. Adds snapshot coverage for the terminal _meta path (a new
capability-advertising scenario) and re-records the fs goldens to show the
diff cards. Applied-hunk (result-time, context-line) diffs need a new
result/event shape and are a follow-up.
RFC: docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md
Behavioral gaps from the coverage audit (line coverage was already 100%; these
close BEHAVIOR gaps):
- fs-local: service-level writeText/editText pre-abort → FS_ABORTED (file
unchanged); concurrent guarded-write race and mixed write-vs-edit race (one
wins, one FS_STALE_VERSION, locks released); edit→edit version refresh at the
provider; the replaceIfVersion post-write version matches a fresh stat. fsio:
a mid-stream abort → FS_ABORTED (previously only pre-abort was covered).
- fs-policy: the agent-without-session owner rung ({agent:{}} → no owner →
createIfAbsent / FS_NOT_OBSERVED); fs/write-intent first-wins (symmetric to
the existing edit-intent test).
- tool-fs: abort-through-the-tool for read/write/edit (isError FS_ABORTED, file
unchanged); a deterministic tool-tier concurrent-edit race via a shared read;
the throwing-fs/observed contract (a throwing listener surfaces as isError but
the mutation already hit disk); the replace_all edit message; parseReadArgs
rejects fractional/NaN offset and zero/negative limit.
- dsh-fs: FsError chains a cause through ErrorOptions.
New with-key e2e (packages/fs/tool-fs/tests/fs-tools.e2e.ts, self-skips without
DEEPSEEK_API_KEY): a real model drives the real read/write/edit tools to create
→ read → edit a file, verified on disk; a second test proves a relative path
resolves against the per-session cwd (factory meta.cwd) not config.cwd. Booted
via a plain tests/harness.ts. Added dsh-agent-loop + dsh-llm-deepseek devDeps.
The fs tools rendered as generic cards (title = tool name, raw file content) in
an ACP editor. Give them tool-owned presentation like bash/subagent have:
- read → title "Read <path>", kind read, offset/limit as rawInput
- write → title "Write <path>", kind edit
- edit → title "Edit <path>", kind edit, a clipped old→new rawInput summary
Add a provider-neutral `locations: { path, line? }[]` to ToolCallPresentation —
the files a call reads/modifies — so a capable editor can follow along / jump to
the file (read carries its offset as the line). The ACP bridge forwards it onto
the wire `tool_call` (ResolvedCallPresentation + call() + the tool_call build in
streamSessionEventUpdate). This flips the `locations` cell in the ACP feature
matrix to supported. The SDK already carries `tool_call.locations`
(ToolCallLocation `{ path, line? }`), so no ACP types leak into dsh-tools.
presentResult is intentionally omitted: it only receives `{ content, isError }`,
not the write/edit outcome, so titling by create-vs-overwrite or replacement
count would mean parsing the model-facing text — the static title stays.
Tests: pure presentCall assertions for all three tools incl. locations and the
edit rawInput clip; a bridge test drives the REAL fs tools through ToolPresenter
and asserts locations reaches the wire tool_call (proven to fail without the
forwarding line). New withFs harness option + dsh-fs devDeps on dsh-acp.
The ACP bridge gives each session its own workspace (SessionHeader.cwd), and
dsh-tool-bash already resolves a bash workdir against it. But ctx.fs.resolve(path)
took no caller context and dsh-fs-local resolved every relative path against a
fixed config.cwd (process.cwd() at plugin load) — so in the ACP demo `write
foo.txt` and `bash cat foo.txt` hit different directories the moment an editor
opens any project other than the server's launch dir.
Thread the session cwd into resolution, mirroring dsh-tool-bash: widen
FileSystem.resolve to resolve(path, opts?: { cwd?: string }); dsh-fs-local bases
a relative path on opts.cwd ?? config.cwd (absolute paths ignore it); the
read/write/edit tools derive it via a shared sessionCwd(exec) helper
(exec.agent?.session.header.cwd). The provider stays free of dsh-agent/dsh-session
— the tool projects exec → cwd and hands over a plain string, per the
explicit-at-seams convention. Backward compatible (the arg is optional).
Tests: fs-local resolve(path,{cwd}) bases relative on the passed cwd / ignores it
for absolute; tool integration writes/reads/edits in a session cwd != config.cwd
and verifies the file on disk (proven to fail on the pre-fix no-cwd path). Fakes
that stood in a bare {session:{}} now carry a header so sessionCwd doesn't throw.
RFC in docs/rfc/implemented/architecture/2026-07-02-fs-per-session-cwd.md.
Rename per review naming decisions:
- package dsh-file-context → dsh-fs-policy (dir, package name, plugin name,
tsconfig refs, importers, type-equiv manifest, generated catalog + module-graph)
- events fs/write-expectation → fs/write-intent, fs/edit-expectation → fs/edit-intent
(fs/observed unchanged); type FsWriteExpectation → FsWriteIntent, "expectation"
wording → "intent" throughout
- exported FileContextExec → FsPolicyExec
Make the implemented RFCs describe what shipped, not the superseded designs:
the 2026-06-17 capability-seam + tool-schemas RFCs no longer place policy on
ctx.fs or use full/partial-view authorization, and the fsspec RFC's ctx.fileContext
service prose is rewritten to the fs/* event-gate reality (freshness-based auth).
Sharpen docs/rfc/implemented/AGENTS.md: a rename is a fact to fix IN PLACE — the
"new RFC" escape hatch is for macro decision reversals only, not renames.
Code fixes from review:
- fsio.ts resolveLocalTarget/probe translate ENOTDIR (a parent path segment is a
file) into the structured FsError taxonomy instead of leaking a raw Node error;
resolve reports FS_NOT_FOUND, probe reports absent. Regression tests proven to
fail on the unfixed code.
- tool-fs HMR test now asserts prompt sections (not just tool schemas) are
withdrawn on disposal.
- fs/observed is a plain (unguarded) ctx.emit: correct the fs-policy comment,
filesystem.md, and tool-fs module doc that wrongly claimed the tool "contains"
a throwing listener; a throw surfaces as the tool's isError result.
- drop the false "loaded by the default product config" claim (no config wires
the fs tools yet), the duplicate ctx.bash service-map row, the stale
FileReadRequest catalog link-map entry, and the fs/fs README EOF blank line;
correct the dsh-fs package.json description.
Two cohesion cleanups on the filesystem tool package:
- Fold window.ts + types.ts + formatReadOutput into one cordis-free
read-render.ts. Line windowing, the FileReadOutcome shape, and output
formatting are one concern (the read tool's rendering); splitting them across
three files added no value. read.ts is now just the tool (schema + I/O).
- Drop observe.ts and emit fs/observed with a plain ctx.emit in read/write/edit.
The event is contractually a synchronous, side-effect-only recorder
(file-context's listener is a WeakMap.set), so the per-call try/catch guarded
against a contract violation that cannot happen under the shipped listener —
defensive code for an impossible case. The event contract (dsh-fs JSDoc,
README, RFC) is updated to state the fire-and-forget semantics plainly.
Adapt the four fs packages to master's single-tsconfig build convention
(lib/types outDir + types path + files allowlist), brought in by the merge.
While doing so, drop dsh-tool-fs's /read//write//edit subpath plugins. They
were the only subpath-export package in the tree and forced bespoke tsdown,
tsconfig path, package.json files, and workspace-constraint handling that no
sibling tool package (e.g. dsh-tool-bash) carries, for a focused-deployment
use case no consumer needed. dsh-tool-fs is now a single root plugin that
registers read/write/edit, mirroring dsh-tool-bash; the per-tool registration
helpers stay internal modules the root composes. The file-context event-gate
RFC is amended to record the narrowed scope.
Invert the tool↔policy control flow per the file-context event-gate RFC.
dsh-tool-fs becomes the executor — it reads/writes/edits through ctx.fs
directly, owns read windowing, and dispatches fs/write-expectation /
fs/edit-expectation (single-slot waterfalls) plus a contained fs/observed
emit. dsh-file-context drops its ctx.fileContext service and becomes a pure
event-gate plugin (observed-state + read-before-edit + version-guarded
write/edit, decided on those events). The provider's version guard becomes
optional so ctx.fs alone is a complete unconstrained text-storage seam:
removing the policy plugin gracefully loses the policy instead of breaking
the tool at a service-injection boundary.
kingwl
Tianyi Cui
Yichen Jiang
Dudu-0223