## Thinking Path
> - Paperclip manages agent work through tasks and runs.
> - Recovery continues assigned work when no live execution path
remains.
> - A recovery sweep can read an in-progress task before its run
completes.
> - The sweep can then observe the successful run after completion has
changed the task status.
> - This pull request checks current status and assignment under the
existing enqueue lock.
> - A stale continuation leaves a skipped wake receipt and creates no
run.
> - Task chat also omits an empty continuation cancelled before it
started because its task had become terminal.
## Linked Issues or Issue Description
Related public work: #10779 and #8419. Those older open changes address
terminal disposition across other recovery paths. This change uses the
existing scheduler guard for productive successful-run continuation and
adds real database lock contention coverage.
**What happened?**
Recovery could combine an old in-progress task snapshot with a newer
successful run. It queued an automatic continuation after the task was
done. Dispatch cancelled that run before it started, but task chat
displayed “Couldn't start” below the successful answer. This can happen
after the native runner's finish result has already been accepted. It
does not require a missing comment.
**Expected behavior**
Productive continuation must remain eligible when enqueueing acquires
the task lock. Completion, cancellation, reassignment, or a move away
from in-progress must prevent creation of the run. Actual execution
stops must remain visible.
**Steps to reproduce**
1. Let recovery select an assigned in-progress task whose latest run
succeeded with productive progress.
2. Hold the task row lock in another transaction and change the task to
done.
3. Let recovery attempt to enqueue while that transaction holds the
lock.
4. Commit completion. Before this fix, recovery creates a redundant run
from the stale snapshot.
**Paperclip version or commit**
Reproduced against master at `4042eb1c4` with deterministic integration
tests.
**Deployment mode**
Built from source with PostgreSQL. The bug is in core recovery and is
not adapter-specific.
## What Changed
- Pass the existing status-and-assignee guard for productive terminal
continuation recovery.
- Preserve a skipped wake receipt with the expected and actual task
state, without creating a run.
- Test actual PostgreSQL lock contention for native and legacy
completion, cancellation, backlog, review, blocked state, and
reassignment.
- Omit empty redundant pre-start cancellations from native and legacy
task chat. Preserve stop markers for runs that started.
- Document recovery eligibility at enqueue time.
## Verification
- All seven new race cases failed before the guard was connected.
- `pnpm -r typecheck` passed.
- `pnpm build` passed.
- `pnpm check:token-gates` passed.
- Task chat suite: 98 tests passed.
- Recovery integration suites: 290 tests passed, including 31
stale-queue tests.
- Full CI verification passed on `7ea71f04d`: all 31 active checks
succeeded, including all test shards, browser tests, build, typecheck,
and canary release dry run. Storybook visual regression was skipped by
its path filter.
- Greptile reviewed this commit at 5/5 with no review threads.
- The local `pnpm test:run` aggregate reported a setup failure in the
unchanged `tool-access-service.test.ts` suite. Its isolated rerun passed
all 231 tests without edits. The duplicate aggregate was stopped after
the complete CI matrix passed; it is not counted as a successful local
full-suite run.
## Risks
Low risk. The backend guard applies only to productive successful-run
recovery. It requires the task to remain in-progress with the same
agent. Other wake sources keep their current policy. The UI change only
suppresses empty redundant cancellations; run records remain available.
No schema change or migration is required.
## Model Used
OpenAI GPT-6 through Codex, with reasoning, repository inspection, code
edits, and local test execution. The exact deployment snapshot and
context window are not exposed by this session.
## Checklist
- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip`
URLs)
- [x] My branch name describes the change and contains no internal
Paperclip ticket id or instance-derived details
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [x] All Paperclip CI gates are green
- [x] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge
---------
Co-authored-by: Paperclip <noreply@paperclip.ing>
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