reviewer: posted reviews can still fail when completion marker parsing or marker verification misses them

[mrcfps]

Summary

• Implement: Implement GitHub issue reviewer: posted reviews can still fail when completion marker parsing or marker verification misses them #225: reviewer: posted reviews can still fail when completion marker parsing or marker verification misses them

Issue body:

Summary

Some reviewer runs successfully post a GitHub review with a Looper marker, but the run is still marked failed because the agent did not emit a parsed __LOOPER_RESULT__ marker or because publish-time marker verification does not find the already-posted review.

This creates false failed reviewer loops and can trigger duplicate follow-up attempts.

Evidence

Posted review but run failed as missing completion marker

Loop 133 (powerformer/looper#125) shows the agent posted a GitHub review successfully:

{"id":4202572321,...,"state":"COMMENTED","commit_id":"fdd4dd124989cae611642ba392bfe462694f01b6"}

The review body includes a Looper marker:

<!-- looper:review id=reviewer:333e9f1e-75cb-466d-9224-13432ab972fe:fdd4dd124989cae611642ba392bfe462694f01b6 head=fdd4dd124989cae611642ba392bfe462694f01b6 outcome=actionable -->

But the loop ended as:

last_error_kind = non_retryable
last_error = Reviewer agent did not report a valid completion marker after publishing review

Publish step failed despite existing reviews

Loops 325 and 333 failed in step=publish with:

Reviewer agent completed but no matching GitHub review marker was found; retrying marker verification before rerunning review

Then their queue items were cancelled with loop_terminated, even though the relevant PR already had reviews/approvals in the review list.

Root cause

The runner has two separate success signals:

1. Agent stdout marker (__LOOPER_RESULT__) parsed by the executor.
2. GitHub review marker verification (<!-- looper:review ... -->).

When (1) is missing, the runner tries to recover by verifying (2), but that verification can miss valid posted reviews due to marker shape, idempotency key mismatch, event type, author, or timing. The fallback then treats the run as failed even though the external side effect already happened.

Relevant code:

• internal/agent/executor.go:499-502 — failed/missing parse marker handling
• internal/reviewer/runner.go:2083-2118 — missing parse marker recovery and final FailureNonRetryable
• internal/reviewer/runner.go:2144+ — publish step verification of pending review markers

Expected behavior

If a Looper-marked GitHub review exists for the expected head, the reviewer run should converge to success or skipped/idempotent completion even when the agent fails to emit __LOOPER_RESULT__.

It should not leave a failed loop after an external review was already posted.

Proposed fix

• Make marker verification tolerant of legacy/current marker id shapes where safe.
• Search recent reviews/comments by expected head and marker prefix before failing missing completion marker cases.
• Treat found existing marker as PendingReview and advance to publish/idempotent completion.
• If verification is inconclusive, prefer retryable_after_resume over non_retryable so the runner can re-check GitHub state before rerunning the full review.
• Add tests where the agent posts a valid marked review but omits __LOOPER_RESULT__.

Issue URL: #225

Agent Summary

Implemented reviewer marker recovery, committed and pushed the branch, but PR creation is still missing because the connector create call was cancelled and gh API calls cannot reach api.github.com.

Issue: #225

Issue URL: #225

Prompt: Implement GitHub issue #225: reviewer: posted reviews can still fail when completion marker parsing or marker verification misses them

Issue body:

Summary

Some reviewer runs successfully post a GitHub review with a Looper marker, but the run is still marked failed because the agent did not emit a parsed __LOOPER_RESULT__ marker or because publish-time marker verification does not find the already-posted review.

This creates false failed reviewer loops and can trigger duplicate follow-up attempts.

Evidence

Posted review but run failed as missing completion marker

Loop 133 (powerformer/looper#125) shows the agent posted a GitHub review successfully:

{"id":4202572321,...,"state":"COMMENTED","commit_id":"fdd4dd124989cae611642ba392bfe462694f01b6"}

The review body includes a Looper marker:

<!-- looper:review id=reviewer:333e9f1e-75cb-466d-9224-13432ab972fe:fdd4dd124989cae611642ba392bfe462694f01b6 head=fdd4dd124989cae611642ba392bfe462694f01b6 outcome=actionable -->

But the loop ended as:

last_error_kind = non_retryable
last_error = Reviewer agent did not report a valid completion marker after publishing review

Publish step failed despite existing reviews

Loops 325 and 333 failed in step=publish with:

Reviewer agent completed but no matching GitHub review marker was found; retrying marker verification before rerunning review

Then their queue items were cancelled with loop_terminated, even though the relevant PR already had reviews/approvals in the review list.

Root cause

The runner has two separate success signals:

1. Agent stdout marker (__LOOPER_RESULT__) parsed by the executor.
2. GitHub review marker verification (<!-- looper:review ... -->).

When (1) is missing, the runner tries to recover by verifying (2), but that verification can miss valid posted reviews due to marker shape, idempotency key mismatch, event type, author, or timing. The fallback then treats the run as failed even though the external side effect already happened.

Relevant code:

• internal/agent/executor.go:499-502 — failed/missing parse marker handling
• internal/reviewer/runner.go:2083-2118 — missing parse marker recovery and final FailureNonRetryable
• internal/reviewer/runner.go:2144+ — publish step verification of pending review markers

Expected behavior

If a Looper-marked GitHub review exists for the expected head, the reviewer run should converge to success or skipped/idempotent completion even when the agent fails to emit __LOOPER_RESULT__.

It should not leave a failed loop after an external review was already posted.

Proposed fix

• Make marker verification tolerant of legacy/current marker id shapes where safe.
• Search recent reviews/comments by expected head and marker prefix before failing missing completion marker cases.
• Treat found existing marker as PendingReview and advance to publish/idempotent completion.
• If verification is inconclusive, prefer retryable_after_resume over non_retryable so the runner can re-check GitHub state before rerunning the full review.
• Add tests where the agent posts a valid marked review but omits __LOOPER_RESULT__.

Issue URL: #225

Closes #225

_{Generated by Looper 0.6.0 · runner=worker · agent=codex}

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[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: acae49acec

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".