Run-11 deep inspection (PR #30 cycle, 4 escalation tiers) traced the
"worktree reset to pinned SHA ... failed ... exit 128" warnings — and
the cycle's misleading ``rebase-failed`` outcome despite the worker's
own ``{"outcome": "resolved"}`` — to two bugs that compounded:
1. task-implementor.md instructed the worker to ``rm -rf {repo_dir}``
after every ``pr_fix`` (rule #7 + procedure step 11). That rule
was correct in the legacy ``git-isolator-util`` workflow where the
worker created its own throwaway clone, but with the Phase 3
pre-clone the worktree is owned by the dispatcher and reused
across tier escalation. Deleting it stranded every subsequent
tier with no workspace AND blew up the dispatcher's between-tier
reset step.
2. ``_reset_worktree_to_pinned_sha`` shelled out to ``git -C <path>``
without checking the path existed; the resulting
``CalledProcessError`` was logged with ``%s`` (just "exit 128"),
so the real cause was invisible without py-spy.
Fixes:
- task-implementor.md: rule #7 + ``pr_fix`` step 11 now spell out
the conditional — delete only if YOU created the clone via
``git-isolator-util``; leave the dispatcher's pre-clone alone.
``issue_impl`` step 10 keeps an unconditional ``rm -rf`` (no PR
pre-clone exists for new-issue work) plus a one-line clarifying
note.
- dispatch_implementer._reset_worktree_to_pinned_sha: detect missing
worktree dir BEFORE shelling to git (returns False with a clear
"disappeared before reset" warning naming the path + pinned SHA);
remove a stale ``.git/index.lock`` if a SIGKILL'd previous-session
git op left one behind; capture stderr from ``CalledProcessError``
and include it (truncated) in the warning so future diagnosis
doesn't require a session-archive deep dive. Fail-soft policy
preserved — escalation still continues, the next session's
``implementer-workspace.py discover`` will fall through to
``git-isolator-util`` when the worktree is gone.
Tests: new tests/auto_agents/test_worktree_reset_resilience.py with
4 classes / 8 tests pinning the missing-dir detection, stale-lock
cleanup, stderr-surfaced-on-failure, happy-path, and degenerate-input
contracts. Suite: 1611 passed / 3 skipped.
Not fixed in this commit (deferred — root cause not clear from one
sample):
- PR #29's first session at run-11 timed out at the 1800s worker
timeout with ``turn 3 task subagent input=0tok output=0tok
wallclock=1756s`` — task subagent stuck with no token usage. Could
be LLM-provider hang, tool loop, or queue stall. Needs another
reproduction + session-archive event-stream inspection to localise.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
drew
f720e30035