## What
FN-8141 follow-up 3. Tightens `deriveExecutorSignalMemory`
(packages/engine/src/overseer-noop-finalize-veto.ts) so a mid-execution
`progressing` overseer observation can no longer clear the executor
no-op-finalize veto.
## Why
The prior derivation took the **newest** executor `observe` entry and
cleared `incompleteWork` whenever it was anything but the canonical
failed reason. But the planner overseer emits a `progressing`
observation ("Task is actively executing in-progress work") the
**moment** a task re-enters execution — long before that execution
finishes. The defeating shape:
> task parks failed-incomplete → requeued → re-execution starts
(overseer observes `progressing`) → execution dies or reverts again
**without** a newer failed observation → newest observation is
`progressing` → `incompleteWork:false` → an empty no-op finalize is
**not** vetoed → the reverted branch launders into `done`.
`progressing` is not "completed green" — the veto's own contract says
the failure must be superseded by a green completion.
## Change
The executor stage in `planner-overseer.ts` emits only
`progressing`/`failed`/`stuck`/`blocked` — **no** green-completion
observation — so the timeline alone cannot distinguish progressing from
completed. Per the follow-up spec, the derivation now:
1. Scans the executor `observe` timeline for the newest
**failed-with-incomplete-work** observation.
2. Keeps `incompleteWork` TRUE unless a durable **clean-completion
task-log marker** is **strictly newer** than that failure park. Reuses
the shared `CLEAN_COMPLETION_MARKERS` set (now exported from
`@fusion/core`, single-sourced with
`evaluateCompletedPromotionFailureProvenance`) so it automatically
tracks sibling follow-up F2's removal of the promotion-output marker.
3. Fails safe on a malformed failure timestamp (stays vetoed).
4. `merger-ai.ts` threads `task.log` into the derivation.
All existing precedence rules are preserved: non-empty merges are never
vetoed; human-control deferral (user-paused / autoMerge:false) still
defers; a missing task fails open.
## Test evidence
- `pnpm --filter @fusion/engine exec vitest run
src/__tests__/overseer-noop-finalize-veto.test.ts
src/__tests__/merger-ai.test.ts` → **59 passed**. New/updated cases:
failed→progressing (no completion) ⇒ still vetoed (the regression this
fixes); progressing between two failed parks (FN-8141 timeline) ⇒
vetoed; clean-completion marker newer than failure ⇒ not vetoed; older
completion marker ⇒ still vetoed; no failure park ⇒ not vetoed; bounded
tail-scan preserved. Integration: empty lane with
failed-then-progressing timeline blocks the finalize; genuinely
re-executed green task finalizes to done.
- `pnpm --filter @fusion/core exec vitest run
src/__tests__/completed-promotion-failure-provenance.test.ts` → 9
passed.
- `pnpm --filter @fusion/engine exec tsc --noEmit` → clean. `pnpm
--filter @fusion/core exec tsc --noEmit` → clean.
- `pnpm verify:fast` → PASS (3 steps green).
🤖 Generated with [Claude Code](https://claude.com/claude-code)
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **Bug Fixes**
* Improved empty-merge finalization safeguards so an in-progress task
cannot incorrectly clear a previously detected incomplete-work failure.
* Finalization can now proceed when a newer clean-completion record
confirms successful completion.
* Added bounded task-history evaluation to ensure completion records are
interpreted safely and consistently.
* **Tests**
* Expanded coverage for progressing, failed, and clean-completion task
timelines.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Co-authored-by: Claude Opus <noreply@anthropic.com>
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