Manual review round, two non-blocking findings:
- CBR-005: _extractText's JSDoc claimed it "walks events in log order",
but it walks the seqs in surface order (the inline comment already said
so) — the exact distinction CBR-001 paid for, since after a replace a
high-seq checkpoint heads the surface before lower-seq retained nodes.
Corrected the JSDoc to match.
- CBR-006: the "HMR safety" suite only asserted registration; the actual
dispose-and-confirm-cleanup test lived under "llm inject", so a reader
searching by name could miss it. Added a disposal test to the HMR-safety
suite (mount via the real plugin fiber with LlmService present so inject
resolves, dispose, assert ctx.get('compact') is undefined) and reframed
the llm-inject test's trailing teardown to point at it.
codex review round 2 (non-blocking) CBR-004: the example's compaction
wiring comment still named the old `agent/pre-request` seam. Renamed to
`agent/pre-step` to match the shipped seam.
Codex round 1 CBR-003: several docs still described compaction as an
`agent/request` waterfall concern, and the implemented compaction RFC
claimed "No changes to dsh-session or dsh-invariants" while the diff
changed both.
- Package READMEs / JSDoc (agent, agent-loop, system-prompt, compact,
compact-basic): compaction now lives on the serial `agent/pre-step`
seam (fired after turn/start, before step/start); the structural guard
is tool-pairing balance (`isToolPairingBalanced`), not step-alignment;
the convergence bound is strict (`>=` rejects).
- architecture.md / core-data-structures/compaction.md: same seam +
predicate + dispatch-mode updates; regenerated cordis catalog.
- Implemented compaction RFC, updated in place to describe shipped
reality: the seam is `agent/pre-step` (@mode serial) fired before
step/start; alignment is surface tool-pairing balance; the convergence
invariant rejects `>=`; and the "no dsh-session/dsh-invariants changes"
claim is corrected — dsh-session gains the tool-pairing predicate and
dsh-invariants drops its `start <= end` replace assertion (a positional
replace makes start > end normal).
Codex round 1 CBR-002: `resolveConfig` rejected only
`summarizationMaxTokens + retainTokens > threshold` (allowing equality),
but `compactIfNeeded` declines only when the estimate is `< threshold`.
At exact equality the post-compaction history sits at the threshold and
re-triggers on the very next check.
Make the bound strict (`>=` rejects), so post-compaction history is
guaranteed strictly below the threshold. Updated the boundary test (the
sum-equals-threshold case is now rejected, not accepted) and added an
"accepts just below the threshold" case; nudged one unrelated config that
incidentally sat at the equality boundary.
Codex round 1 CBR-001: a head-anchored compaction checkpoint was
mis-classified by the log-position step-alignment scan, so a second
auto-compaction over a checkpoint-headed surface silently failed.
Root cause: `isStepAlignedStart/End` scanned the LOG by seq, but a
`replace` op lands a checkpoint at a high log seq whose SURFACE position
is the head — its log neighbours (the open step's assistant/message) are
not its surface neighbours, so the forward scan wrongly reported mid-step.
Fix, per the agreed direction:
- Replace the two log-position predicates with one surface-anchored
helper `isToolPairingBalanced(nodes, events, beforeSeq)` in
`dsh-session` (renamed step-boundary.ts → tool-pairing.ts). A cut is
balanced when no unanswered tool-call precedes it on the surface; a
region is collapsible iff both edges are balanced cuts. The open-tail
and free-node cases fall out of the same counter. It also throws on a
corrupt surface (a tool/result with no matching call).
- Move compaction off the in-step seam to a new "pre-step" seam fired
after turn/start and before step/start, so a compaction's log-only
compact/* records and its replacement node land cleanly OUTSIDE any
step (the honest structure crash-safety relies on). Renamed the event
agent/pre-request → agent/pre-step and switched its dispatch from
parallel → serial (listeners mutate the surface as a side effect;
serial isolates them so concurrent appends can't interleave). Extended
the catalog generator to accept @mode serial.
Regression coverage: a real-loop test driving an auto-compaction asserts
the landed checkpoint is a balanced cut on both sides; unit tests pin the
checkpoint case, the mid-step injection case, multi-call steps, and the
corrupt-surface guard. Proven red on the old log-position logic.
Reform the compaction blueprint so a runaway turn survives and the design
stops drifting across review rounds:
- Drop in-flight-turn protection ("layer 2"). Retention is a uniform tail→head
whole-unit walk; the only structural guard is step-alignment. A single turn
that alone exceeds the window now compacts its own early closed steps instead
of being retained verbatim (the failure mode that motivated this).
- Move auto-compaction off the agent/request waterfall onto a new awaited
agent/pre-request loop seam, fired before history derivation. Compaction
mutates the surface; the loop derives once from the result — no double-derive,
and a listener structurally cannot act on not-yet-derived messages.
- Tighten compactIfNeeded to required (session, system, model, signal).
- Enforce a single-pass convergence invariant in resolveConfig: reject configs
where summarizationMaxTokens + retainTokens exceeds the threshold, so a
compaction can never immediately re-trigger.
- Document the crash vs recoverable failure taxonomy; core session repair stays
compaction-agnostic (a log-only orphaned compact/start is inert).
- Wire dsh-compact-basic into examples/coding-agent and add a with-key
compaction e2e (compaction's first real-world exercise + runaway net).
- Rewrite the RFC to encode the blueprint and move it to implemented/.
The runaway-turn snapshot is a named deferred follow-up: dsh-llm-replay cannot
yet serve the interleaved summarization model call.
Collapses the per-round review churn of the prior compact-basic branch into a
single clean baseline on top of compact-interface, so the upcoming retention
refactor lands as fresh, well-scoped commits rather than stacking on a history
of fixes that are being superseded.
P1: both merge parents shipped SCHEMA_VERSION=3 for different layouts (surface
columns vs seed_length), so an on-disk 3 was ambiguous and wrongly accepted.
Bump to 4 (merged layout) so the version check rejects both sibling v3s.
P2: a surface-eligible event with no surfaceOp lands in the log but vanishes
from deriveMessages() (surface is the sole derivation path). The typed append
overload enforces the marker only when the type arg is a literal; it collapses
to optional when widened to the union (a caller iterating raw events). Guard at
runtime in both append() and the seed constructor — no backward-compat for
surface-less logs. Shared seed fixtures carry surfaceOp explicitly and the
appendLog helper forwards it verbatim (no synthesized default). Exports
isSurfaceEligibleType. Regression tests for all three, each verified to fail
on the unfixed code.
Gates: typecheck, test (1115), snapshot (14), doc-sync, lint, build, hygiene green.
Reconciles the session-surface work (surfaceOp/sourceEventSeqs provenance as
the sole derivation path) with master's worktree-subagent series (fork-seed
boundary + out-of-process subagent backends).
Semantic reconciliations beyond the textual auto-merge:
- SQLite SCHEMA_VERSION: both sides bumped 2->3. Merged to a single v3 carrying
BOTH column families — master's seed_length on `sessions` and surface's
source_event_seqs/surface_op on `events`. writeRow + both INSERT sites bind
the full set; the schema doc lists all three added columns as the v2->v3 gap.
- agent-loop runStep request: master's `sessionId: session.id` and surface's
per-append surfaceOp/sourceEventSeqs coexist (different regions).
- Fork seed + surface: a fork seeds the child from the parent's LIVE events,
which now carry surfaceOp, so the child's surface rebuilds correctly. Verified
end-to-end — the subagent-fork replay recalls the inherited "SAFFRON" codeword
through the seeded prefix.
- Subagent snapshot fixtures (recorded pre-surface) re-enriched via KEYLESS
deterministic replay: only surfaceOp/sourceEventSeqs added onto existing
recorded lines (matched by seq), no recorded value changed. Not re-recorded
against the live API.
Gates: typecheck, test (1112), test:snapshot (14), doc-sync, lint, build,
hygiene all green.
The seed-boundary change made fork-child replay route correctly but shipped
with no recorded fork scenario — the seedLength slice was exercised only by
llm-replay unit tests and a persistence round-trip, never by the full-transcript
snapshot tier. Add two recorded scenarios that drive a real fork child through
it:
- subagent-fork: parent completes a turn, then forks one child (child fixture
carries a non-zero seedLength, the boundary the replay slice consumes).
- subagent-mixed: parent completes a turn, then delegates once via spawn
(seedLength 0) and once via fork (non-zero seedLength) in one transcript —
the first scenario to drive two subagent backends at once, exercising both
branches of the slice.
Both need a completed turn-1 so the fork seed is a non-empty completed-turn
prefix (a turn-1 fork seeds empty = spawn, which would not exercise the slice).
Removing the slice turns both scenarios red (the fork child receives the
parent's recorded chunks), proving the guard bites.
ACP (out-of-process) subagent replay remains a different shape, still tracked
as TODO(acp-subagent-replay).
A fork subagent seeds its child session with a prefix of the parent's log, and
that seed becomes the child's persisted log — so a fork child's .jsonl begins
with the PARENT's events, including the parent's assistant/chunk events. The
snapshot replay harness derived a child's script from its whole log, which would
replay the parent's recorded responses as the child's model calls. Spawn-only
scenarios never hit it, but a fork snapshot would mis-route silently.
Record the seed boundary and skip the inherited prefix at replay:
- SessionHeader gains an optional `seedLength` (how many leading events were
inherited via a seed), threaded through CreateSessionOptions/CreateAgentOptions
meta and stamped by the fork backend (= seeded-prefix length; absent for spawn).
It is EXPLICIT, never inferred from seed.length: a resume seeds the whole stored
log, so the resume path passes the persisted boundary back.
- Both persistence backends round-trip it: JSONL header line, SQLite seed_length
column. The SQLite table change bumps SCHEMA_VERSION 2->3; per the pre-release
stance the backend rejects an older user_version on open with NO migration.
- llm-replay's parseSessionHeader reads seedLength and loadSessionScripts derives
a child script from events AFTER the boundary. seedLength is 0 for spawn, so
spawn replay is byte-for-byte unchanged.
Closes the routing-correctness gap the per-session snapshot replay RFC under-
stated; a recorded fork scenario remains a future addition but now derives
correctly. RFC: docs/rfc/implemented/testing/2026-06-22-fork-child-replay-seed-boundary.md.
Regression coverage: a fork child fixture whose seeded prefix carries a parent
chunk (derived script must exclude it, proven red without the slice); a seedLength
persistence round-trip through the shared coordinator contract (both backends);
the fork backend stamping it; resume preserving it from the persisted header.
The acp-agent cordis configs loaded the fork backend but bound only one
dsh-tool-subagent (to spawn), so the comment's claim that a multi-child scenario
could exercise both transports was false — fork was loaded but unreachable by
the model. Register a second dsh-tool-subagent bound to fork with a distinct
toolName (subagent_fork), matching the coding-agent demo, in both cordis.yml
(record/demo) and cordis.snapshot.yml (replay). Snapshot goldens are unchanged
(the transcript does not capture the available-tool list).