Codex Desktop: background turn reported completed/interrupted while JSONL continues without final_answer or task_complete #38972

Summary

Codex Desktop/app-server can report a background-created turn as completed/interrupted while the underlying rollout JSONL is still receiving events and has no final_answer or task_complete.

This appears to affect threads created through app-server thread/start + turn/start, where the external orchestrator only receives acceptance, not final completion.

Environment

• Codex Desktop release observed in logs: 26.810.41047
• app-server version observed in logs: 0.148.0-alpha.9
• session cli_version: 0.146.0
• Host: local macOS
• Model provider: codex_local_access
• Timezone used below: Asia/Shanghai, UTC+8

Evidence

Example B, no compaction/handoff case:

• Thread: 01a00ee4-6014-7632-ae22-0aef4775476d
• Turn: 01a00ee4-68c7-7492-9f8f-31fcd00750ae
• Local JSONL: $HOME/.codex/sessions/2026/08/17/rollout-2026-08-17T16-44-02-01a00ee4-6014-7632-ae22-0aef4775476d.jsonl
• At 2026-08-17 16:52:07 UTC+8, the JSONL had 224 lines, latest event timestamp 2026-08-17T08:52:07.812Z.
• The JSONL contained no final_answer and no task_complete.
• read_thread returned the turn as status="interrupted", error=null, completedAt=null.
• wait_threads(timeoutMs=0/5000) woke with reason="turnCompleted", but the same response still had latestTurn.status="interrupted" and completedAt=null.
• During polling, the JSONL kept growing, e.g. 206 -> 216 -> 224 lines, showing events were still being appended after the turn was treated as completed/interrupted.
• Desktop log around 2026-08-17T08:46:50.390Z showed maybe_resume_success ... latestTurnStatus=interrupted ... markedStreaming=true; the JSONL continued appending after that.

Example A, compaction/handoff-adjacent case:

• Thread: 01a00ec3-e645-7822-91db-1257005fd4c4
• A phase="final_answer" handoff summary appeared mid-turn at 2026-08-17 16:12:41 UTC+8.
• The actual same-turn task_complete was later at 2026-08-17 16:17:19 UTC+8.
• Desktop appeared to treat the turn as completed before the real task_complete.

Expected Behavior

• wait_threads should not wake with reason="turnCompleted" unless the turn has a real terminal state.
• read_thread and Desktop should not present a turn as completed/interrupted while the same turn is still receiving JSONL events.
• A mid-turn phase="final_answer" should not be treated as task completion without task_complete.

Actual Behavior

• wait_threads can wake as turnCompleted while the latest turn is still interrupted with completedAt=null.
• Desktop/read model can diverge from the underlying rollout JSONL stream.
• Users see background Codex tasks as if they stopped or completed halfway.

Impact

External orchestrators that create Codex tasks through app-server cannot reliably tell whether a turn genuinely finished. Desktop UI also makes background tasks look like they stopped or completed halfway.

Suspected Area

Codex Desktop/app-server read model or wait semantics for background-created turns. This is not limited to context compaction: compaction/handoff final_answer is one trigger shape, but the second example reproduces without final_answer or task_complete.

Diagnostics Snippets

Minimal excerpts only; full logs/JSONL may contain local paths, prompts, project names, message content, and tool outputs.

wait_threads contradiction

{
  "wake": {
    "reason": "turnCompleted",
    "turnId": "01a00ee4-68c7-7492-9f8f-31fcd00750ae",
    "threadId": "01a00ee4-6014-7632-ae22-0aef4775476d"
  },
  "latestTurn": {
    "id": "01a00ee4-68c7-7492-9f8f-31fcd00750ae",
    "status": "interrupted",
    "error": null,
    "completedAt": null,
    "durationMs": null
  }
}

JSONL terminal-event check

{
  "line_count": 224,
  "last_timestamp": "2026-08-17T08:52:07.812Z",
  "finalLines": [],
  "completeLines": []
}

Desktop resume log summary

At 2026-08-17T08:46:50.390Z, Desktop logged a successful resume for the same thread with:

maybe_resume_success ... latestTurnId=01a00ee4-68c7-7492-9f8f-31fcd00750ae latestTurnStatus=interrupted markedStreaming=true ... turnCount=1

The rollout JSONL continued appending after this log line.