[baxen]

What

With goose, a send (or reply_in_subthread) marked final: true now ends the goose turn, as it already does for Claude Code (continue: false) and Pi.

Until now AcpSession.finished() only settled the Buzz work. goose went on with one more model call, and Buzz never posted its text. In that call, agents that had put final on a message promising more work ("I'll start the PR…") noticed the mistake, decided the protocol made them stop, and dropped the work. Buzz also counted the work as done while goose was still running.

How

goose v1.57.0 has no way for a tool result to end a turn. PostToolUse hooks only notify, and Stop hooks can only block. ACP session/cancel does it cleanly:

• goose finishes the step it is in and saves every tool result that completed. Unfinished calls in the batch are saved as interrupted (goose-agent/src/machine.rs finalize).
• The prompt answers stopReason: "cancelled". AcpSession already handles that for a turn the owner did not stop.

Two races are handled in acp/session.ts:

1. When to cancel. A cancel sent from finished() reaches goose before goose records the send result, so goose would save the send as interrupted and the model might resend it next turn. goose reports a batch's results together, once every call has one (ops_toolcalling.rs). So after finished(), the session cancels on the first tool_call_update that is completed or failed.
2. Messages in between. A message that arrives between finished() and that update is queued as the next turn instead of steered into the turn being cancelled.

finished() keeps its existing guard: when another message is waiting for its answer, the turn is not ended.

Non-goals: no change to the final prompt or tool description, and nothing in goose.

Validation

• src/bundled/goose/goose.test.ts: three new tests. The turn is cancelled only after the completed result arrives, and the next turn's results don't cancel it. A message arriving mid-ending runs as the next turn. No cancel while another message waits. The first two fail on origin/main and pass here.

• vitest run src/bundled/goose src/features/agent-harness src/features/agents src/bundled/mesh-compute: 1984 passed. tsc --noEmit is clean.

• Live goose-acp 1.57.0 (GOOSE_ACP_BIN=… vitest run src/bundled/goose/goose.live.test.ts). The new test "ends the turn after a final send, keeping the send's result" asserts:

  • exactly one session/cancel after the final send;
  • on the next turn, the model reports the send's actual result (Sent.), so goose did not save the send as interrupted.

  It fails on origin/main (no cancel) and passes here.

  • Three other live tests fail the same way on origin/main and on this branch: they expect { ok: true } where finished() returns { ok: true, answered: true }. That predates this change, and I left it alone.

Deferred

• No independent agent review yet.
• Not exercised in the running app. Steps to try: in a goose agent's chat, ask for a reply. The agent's activity indicator should clear right after its final message, with no trailing "Writing reply". Another message sent in that moment should get its own turn.