[BUG] codex:codex-rescue hangs in worktrees when run_in_background is used #198

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1. mr-lee

   closed this as completedon Apr 9, 2026
2. mr-lee

   reopened this on Apr 9, 2026
3. mr-lee

   changed the title [-][BUG] Broker singleton assumes one cwd per repo — parallel worktree dispatch hangs silently[/-] [+][BUG] codex:codex-rescue hangs in worktrees when run_in_background is used[/+] on Apr 9, 2026
4. mr-lee commented on Apr 9, 2026

   

   mr-lee

   on Apr 9, 2026

   Author

   More actions

   Corrected Root Cause

   My initial analysis was wrong — resolveStateDir() is fine. The actual root cause is the interaction between codex:codex-rescue, run_in_background, and CC's worktree lifecycle.

   What happens

   1. codex:codex-rescue agent is dispatched with isolation: "worktree" (CC creates a temporary git worktree)
   2. The rescue agent calls codex-companion.mjs task --write with run_in_background: true on the Bash tool
   3. Bash returns immediately ("Command running in background...")
   4. The rescue agent returns "Codex task dispatched in background" and exits
   5. CC sees the agent returned with no file changes → deletes the worktree
   6. Codex is now running in a deleted directory → hangs indefinitely at "Turn started"

   When does the rescue agent use run_in_background?

   Two cases:

   • Explicitly: The codex-cli-runtime skill interprets --background in the task text as a signal to set run_in_background: true
   • Implicitly: For large/complex prompts with long timeouts (600s), Claude sometimes independently decides to background the call

   Confirmed repro

   # This succeeds (no --background, rescue agent waits):
   Agent(subagent_type="codex:codex-rescue", isolation="worktree", prompt="Create foo.txt with content hello")
   
   # This fails (--background, rescue agent returns immediately, worktree cleaned):
   Agent(subagent_type="codex:codex-rescue", isolation="worktree", prompt="Create foo.txt with content hello. --background")
   

   Three parallel non-background dispatches all succeed — Codex handles concurrency fine. The issue is purely about early worktree cleanup.

   Suggested fix

   Add to codex-cli-runtime SKILL.md:

   - NEVER use `run_in_background` on the task Bash call. The rescue agent must wait for Codex to complete and return its stdout. Backgrounding causes the parent worktree agent to exit early, which triggers worktree cleanup before Codex finishes.
   

   And strip --background from the routing flags rather than converting it to run_in_background:

   - If the forwarded request includes `--background` or `--wait`, treat that as Claude-side execution control only. Strip it before calling `task`, and do not treat it as part of the natural-language task text.
   

   The skill already says "Strip it before calling task" but should add "and do NOT set run_in_background on the Bash call."

   Impact

   Any codex:codex-rescue dispatched with isolation: "worktree" where the rescue agent uses run_in_background will silently fail. The Codex task hangs in a deleted directory with no error.
5. tgkim-openerd

   added a commit that references this issue on May 17, 2026

   fix(rescue)!: unify --background / --wait policy + drop auto-promote …

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   c449aa2
6. tgkim-openerd

   added 2 commits that reference this issue on May 27, 2026

   docs(rescue): never background a rescue task inside a worktree (opena…

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   c4537e4

   docs(v2.0.0): sync README + MIGRATION_v2.0.md + TROUBLESHOOTING.md wi…

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   aed0475
7. tgkim-openerd

   added a commit that references this issue on Jul 9, 2026

   fix: telemetry 계측 정합 + job 생명주기 + broker 소유권 (v2.4.0, #28 root cause) (…

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   1328dc5