Merge branch 'worker/cb-137-ask-ticket-e7760c-2' of https://git.ltms.dev/fleet/fleetd into worker/cb137-ambiguous-task-4df3d8-4

REPORT-cb137.md

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+# CB-137 / fleetd issue #137 — report
+
+## Real root cause (not the hypothesis in the ticket)
+
+I read `MessageService.java` and `Rendezvous.java` before changing anything. The mechanism is real,
+but the exact place it happens is `MessageService.answer()`, not "the reply goes to the inbox on
+purpose" in general.
+
+1. A lead delegates with `fleet_send{wait:false}` → `sendAsync()` creates a `Task` and runs `send()`
+   on a background virtual thread with a 30-minute internal budget (`ASYNC_TIMEOUT_MS`).
+2. The worker calls `fleet_ask`. That resolves the open rendezvous waiter with `Kind.QUESTION`, so
+   `send()` returns immediately and the `Task` is left open (its `future` stays unresolved — see the
+   comment in `sendAsync`'s lambda: "Keep the accepted owner until answer() finishes it").
+3. The lead answers with `fleet_send{turnId, content}`. This calls `FleetMcp.answer()` →
+   `MessageService.answer(turnId, content, timeout)`. The `timeout` here is **not** the generous
+   30-minute async budget — it is the MCP tool's own bounded wait: `DEFAULT_TIMEOUT_MS = 25_000`,
+   clamped to at most `MAX_TIMEOUT_MS = 120_000` (`FleetMcp.java:71-72,495,512`). This is the same
+   ~60–120s window every blocking `fleet_send` call is capped at (documented elsewhere as "the
+   caller's own MCP client call timeout").
+4. `answer()` opens a **fresh** rendezvous waiter for the worker session and blocks on it for at most
+   that window. If the worker's resumed turn takes longer than that to actually finish (very
+   plausible — the resumed turn can mean more edits, a build, a commit, a push, opening a PR), the
+   wait times out. On timeout, `answer()`'s `finally` block unconditionally calls
+   `rendezvous.close(workerSession, reply)`, **removing the waiter from the map**, and returns
+   `Outcome.TIMED_OUT_WORKING` to the lead.
+5. The worker keeps working, unaware anything happened, and eventually calls `fleet_reply`. That
+   reaches `MessageService.reply(session, content)`, which tries `rendezvous.resolve(session,
+   content)` — but the waiter was already closed in step 4, so `resolve` returns `false`. `reply()`
+   then falls back to `inbox.publish(...)` and marks `strandedReplies.put(session, true)`
+   (CB-640 bookkeeping) — the reply is safely held, but **the async `Task`'s `future` is never
+   completed**.
+6. `fleet_poll{ticket}` keeps returning `PENDING` forever (the `Task` never resolves) — until the
+   lead eventually calls `fleet_stop`. That fires `sessions.onRelease` → `messages.abandon(target,
+   reason)` (`Fleetd.java:481-497`), where `reason` is built with the exact text from the bug report
+   ("the worker session was released before it replied; worktree=... branch=... snapshot=...",
+   `Fleetd.java:484-487`). `abandon()`'s loop finds the still-open `Task` (`question == null`, future
+   not done) and completes it as `WORKER_FAILED` with that misleading reason — even though the
+   worker's real reply is sitting, intact, in the inbox the whole time.
+
+So: the reported behaviour is correct, and the specific trigger is `answer()`'s own bounded wait
+being shorter than the worker's real resumed-turn time — not anything to do with the ~55s
+`fleet_ask` window itself (that part, issue #61, is untouched).
+
+## Fix
+
+Two changes in `fleetd/src/main/java/dev/ltms/fleet/msg/MessageService.java`, both scoped to the
+ticket/reply routing and the terminal-state text — `fleet_ask`'s own window and mechanics are
+untouched.
+
+**1. `reply()` — priority 1 (the ticket resolves with the real reply).**
+Before falling back to the inbox, `reply()` now looks for an async `Task` that is specifically in the
+"already answered but not yet resolved" state (`question == null`, `turnId != null` — set once
+`answer()` has cleared the question but before anything completed the future, `!future.isDone()`).
+If one exists for this `target`, the worker's reply completes that `Task`'s future directly as
+`Outcome.REPLIED` with the real content, and the reply never touches the inbox at all. A task that
+was never asked has `turnId == null` and can never match, so ordinary (no-`fleet_ask`) delegations
+are unaffected — they already resolve through the pre-existing rendezvous fast path.
+
+I chose this over leaving `answer()`'s own timeout behaviour untouched and instead keeping its
+rendezvous waiter open in the background: that alternative works but reopens the "at most one
+waiter per session" invariant (`Rendezvous.open` throws on a double-open) to a new class of races
+with a fresh send arriving mid-window. The `send()` path already guards against sending into an
+answered-but-still-resolving worker via `hasAsyncQuestion(target)` (checks `asyncTasksByTurn`,
+which still holds the task until it resolves), so routing through `reply()` gets the same protection
+without touching `answer()`'s waiter lifecycle at all — the smaller, safer diff.
+
+**2. `abandon()` — priority 3 (required independently, "even if you fix (1)").**
+Before marking any of a released target's still-open tasks `WORKER_FAILED`, `abandon()` now checks
+`hasStrandedReply(target)` (the existing CB-640 fact — true whenever the *last* `reply()` for this
+target fell through to the inbox). If true, it drains the inbox (`recoverStrandedReply`) and — if it
+actually finds a message — completes the task as `REPLIED` with that real content instead of writing
+the failure. This is deliberately a **separate** check from fix 1: fix 1 already prevents the
+inbox-stranding from happening in the exact scenario this ticket describes, so by the time
+`abandon()` runs the task is normally already resolved and `abandon()`'s `complete()` call is a
+harmless no-op. This second check exists so that if some *other* future path ever strands a reply
+in the inbox without resolving its ticket, `abandon()` still refuses to report a false failure —
+"if a reply reached any sink for that turn, the terminal state is done," per the ticket. I verified
+both are required by disabling each independently and confirming the two new tests fail (see below).
+
+**Priority 4 (the snapshot/worktree hint).** Handled as a consequence of both fixes rather than a
+separate branch: once a task resolves as `REPLIED` (via either fix), `abandon()` never calls
+`new Reply(Outcome.WORKER_FAILED, reason)` for that task at all, so the "the worker session was
+released before it replied; worktree=... branch=... snapshot=..." text is never constructed or
+attached to that ticket's outcome. It still appears, correctly, for a task that never got a reply
+(the existing `abandonFailsEveryPendingAsyncTicketForTheReleasedTarget` /
+`anAbandonedAsyncTaskPollsAsFailedNotPending` tests still pass unchanged).
+
+**Priority 2** was not needed — fix 1 makes `fleet_poll{ticket}` return the actual reply (the
+higher-priority option), so I did not fall back to "the ticket merely resolves as done with no
+content."
+
+## Tests — driven through the real delegation path, not the reply sink directly
+
+Both new tests in `fleetd/src/test/java/dev/ltms/fleet/msg/MessageServiceTest.java` go through
+`sendAsync` → `injectDelivery` → `ask` → `answer` (with a short timeout, so it genuinely times out,
+mirroring the ~25–120s real MCP-call bound vs. a longer resumed turn) → `reply` → `poll`/`abandon`.
+No test constructs a `Reply` and hands it to a sink directly.
+
+- `aReplyAfterAnswerTimesOutStillCompletesTheAsyncTicket` — asserts `fleet_poll{ticket}` (via
+  `messages.poll`) reaches `Phase.DONE` with the worker's actual reply text and
+  `replySource() == "reply"`, and that `hasStrandedReply(T)` stays `false` (proves the reply never
+  touched the inbox at all — fix 1 caught it).
+- `fleetStopAfterAnOrphanedReplyDoesNotFailTheTicket` — same setup, then calls `abandon(T, "the
+  worker session was released before it replied")` (what `fleet_stop` triggers) and asserts it
+  returns `false` (no failure recorded) and the ticket still polls `DONE` with the real reply.
+
+**Proof both fail without the change.** I temporarily short-circuited both new private methods
+(`askAnsweredAsyncTask` → always `null`, `recoverStrandedReply` → always `null`) — i.e. disabled
+both fixes — and ran just these two tests:
+
+```
+[ERROR] Tests run: 2, Failures: 2, Errors: 0, Skipped: 0
+dev.ltms.fleet.msg.MessageServiceTest.aReplyAfterAnswerTimesOutStillCompletesTheAsyncTicket
+  org.opentest4j.AssertionFailedError: expected: <DONE> but was: <PENDING>
+dev.ltms.fleet.msg.MessageServiceTest.fleetStopAfterAnOrphanedReplyDoesNotFailTheTicket
+  org.opentest4j.AssertionFailedError: a reply already arrived, so nothing here is a genuine failure
+  ==> expected: <false> but was: <true>
+```
+
+This is the exact bug: the ticket stays `PENDING` forever, and `abandon()` reports `true` (a
+failure) even though a reply had already arrived. I then restored both fixes (verified with
+`grep -n "TEMP #137-proof"` finding nothing) and re-ran — both pass.
+
+## Build
+
+Ran from `fleetd/`, unpiped, full output read (not `| tail`):
+
+```
+mvn clean install
+...
+[INFO] Tests run: 1039, Failures: 0, Errors: 0, Skipped: 0
+[INFO] BUILD SUCCESS
+[INFO] Total time:  36.315 s
+```
+
+Main was at 1037 tests; this branch adds the 2 new tests above → 1039, all green, `exit=0`.
+
+## What I could NOT check
+
+- No IDE tooling is mounted for me (worker), so no `ide_diagnostics`/IntelliJ inspection pass — only
+  `mvn clean install` (compiler + full test suite), as the worker procedure allows.
+- I cannot restart the daemon or dogfood this live — I have no forge/daemon control. This is
+  unverified against a real herdr pane, a real MCP client's ~60s call cap, or a real worker session;
+  everything above is verified only through the JUnit fixture's simulated timing
+  (`FakeHerdr`/`injector.onStatus`/direct `messages.answer(...,150)` calls), not a live fleet.
+  A primary should still consider a short live dogfood (an async delegation that asks, gets answered,
+  and takes longer than ~2 minutes to reply) before calling this closed.
+- I did not touch, and did not re-verify, the `fleet_ask` ~55s window itself (issue #61) — out of
+  scope per the brief.
+
+## Scope note (not investigated further)
+
+`answer()`'s nested/double-`fleet_ask` case (the worker asks a second question before ever
+replying to the first answer) has some pre-existing behaviour around which `turnId` a `QUESTION`
+resolution gets attributed to that I did not fully untangle — it predates this change, my fix does
+not touch it, and it is unrelated to the reported defect. Flagging only; not investigated further.
+
+## Handoff
+
+- Branch: `worker/cb-137-ask-ticket-e7760c-2`
+- Worktree root: `/Users/dai.ha/LTMS/.bridged-worktrees/734324-2`
+- Files changed:
+  - `fleetd/src/main/java/dev/ltms/fleet/msg/MessageService.java`
+  - `fleetd/src/test/java/dev/ltms/fleet/msg/MessageServiceTest.java`
+  - `REPORT-cb137.md` (this file)
+- Build: `Tests run: 1039, Failures: 0, Errors: 0, Skipped: 0` / `BUILD SUCCESS` (verbatim above)