fix(agent-loop): latch wakes landing in the cancel-convergence window

.agents/notes/implemented/architecture/2026-07-16-explicit-turn-cancellation.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write .agents/notes/implemented/architecture/2026-07-16-explicit-turn-cancellation.md
-2026-07-16-explicit-turn-cancellation.md: ca56c77a097e3008a50c2aec24040a4f4b6f0ba3
-2026-07-16-explicit-turn-cancellation.zh.md: bf410e5c7284a9c9914edbd14445074e71dd6943
+2026-07-16-explicit-turn-cancellation.md: 2b7cb8cc77184edf1331764d28aefe748c1614a1
+2026-07-16-explicit-turn-cancellation.zh.md: 68089e2c48d239afbff4c10cba5a202b4b6ff262

.agents/notes/implemented/architecture/2026-07-16-explicit-turn-cancellation.md

@@ -18,7 +18,7 @@ An interrupted live turn ends with the coarse durable `{ kind: 'aborted' }` outc
 
 AgentLoop privately owns one `TurnCancellation` per prospective turn. It installs the holder before notifying `agent/status = running`, retains its single `AbortController` through inbox claim, `agent/pre-step`, prompt assembly, every step, model and tool execution, and `agent/turn-stopping`, then clears the exact holder immediately before publishing `turn/end`. Terminal event observers and the following durability flush therefore cannot cancel already-completed turn work even though driver status may remain `running` until the flush settles. Every participating method, event, and request value receives that same explicit signal; the next turn receives a fresh signal.
 
-The driver keeps only a cause-less pre-run marker for queued work cancelled before a turn is claimed. An effective `cancel()` emits the observe-only `agent/cancel-requested` notification with its resolved typed cause before clearing queued and steering work or aborting the holder; notification failures cannot veto the stop, and an idle call emits nothing. Work synchronously queued by a notification observer is included in that clear, while work queued by a later signal abort observer belongs to the next turn. If a `running` listener synchronously cancels old work and sends a replacement, the driver discards the aborted holder and creates a fresh one for the replacement. Repeated cancellation is first-wins for the active holder, while later calls may still clear newly queued pending work.
+The driver keeps only a cause-less pre-run marker for queued work cancelled before a turn is claimed. An effective `cancel()` emits the observe-only `agent/cancel-requested` notification with its resolved typed cause before clearing queued and steering work or aborting the holder; notification failures cannot veto the stop, and an idle call emits nothing. Work synchronously queued by a notification observer is included in that clear, while work queued by a later signal abort observer is latched and runs when the aborted activity converges to idle — a `disposed` cancel leaves it parked ([cancel-convergence wake latch](../bug-fix/2026-08-07-cancel-convergence-wake-latch.md)). If a `running` listener synchronously cancels old work and sends a replacement, the driver discards the aborted holder and creates a fresh one for the replacement. Repeated cancellation is first-wins for the active holder, while later calls may still clear newly queued pending work.
 
 The explicit event signatures pass a single payload object: agent-scoped events carry `agent` and `signal` in the payload with `next` last, and the remaining seams keep `signal` immediately before a waterfall's final `next`. `PreStepContext` and `RequestFailureContext` are retired, with their fields folded into the `agent/pre-step` and `agent/request-error` payloads ([payload-object events](2026-08-06-agent-event-payload-objects.md)). Pre-step entry, request configuration, request-error recovery, model generation, tool execution, approval, turn stopping, and subagent or workflow requests all receive the current signal. Hook bridges must also supply `RunHookOptions.signal`, so a turn cancellation reaches the bash executor's process-group kill and join boundary. `SystemPrompt.assemble()` carries `signal?: AbortSignal` in `AssembleContext` because that object is an explicit request value that can also represent signal-less assembly outside a turn. Listeners may cooperate with the signal but must not retain it to control another turn.
 

.agents/notes/implemented/architecture/2026-07-16-explicit-turn-cancellation.zh.md

@@ -18,7 +18,7 @@ Agent 拥有仅用于运行时的 `AgentCancelCause` 联合类型 `{ kind: 'user
 
 AgentLoop 为每个待启动轮次私有地持有一个 `TurnCancellation`。它在通知 `agent/status = running` 前安装该持有者，使其中唯一的 `AbortController` 持续覆盖 inbox 领取、`agent/pre-step`、提示词组装、每个步骤、模型与工具执行以及 `agent/turn-stopping`；随后在发布 `turn/end` 前立即清除所安装的那个持有者。因此，即使驱动器状态可能在持久化刷新结算前保持 `running`，终态事件观察者及其后的持久化刷新也无法取消已完成的轮次工作。所有参与的方法、事件和请求值都会收到同一个显式 signal；下一个轮次会收到全新的 signal。
 
-对于轮次被认领前已取消的排队工作，驱动器只保留一个不携带取消原因的运行前标记。实际生效的 `cancel()` 会先发出仅供观察的 `agent/cancel-requested` 通知并携带最终确定的类型化取消原因，然后才清除排队工作和 steering（中途引导）工作或中止持有者；通知失败不能阻止此次停止，空闲状态下调用则不发出任何通知。通知观察者同步加入队列的工作也会被这次清除，而稍后由 signal 中止观察者加入队列的工作属于下一个轮次。若 `running` 监听器同步取消旧工作并发送替代提示词，驱动器会丢弃已中止的持有者，并为替代提示词创建全新的持有者。同一活跃持有者上的重复取消遵循首次请求优先，后续调用仍可清除新入队的待处理工作。
+对于轮次被认领前已取消的排队工作，驱动器只保留一个不携带取消原因的运行前标记。实际生效的 `cancel()` 会先发出仅供观察的 `agent/cancel-requested` 通知并携带最终确定的类型化取消原因，然后才清除排队工作和 steering（中途引导）工作或中止持有者；通知失败不能阻止此次停止，空闲状态下调用则不发出任何通知。通知观察者同步加入队列的工作也会被这次清除，而稍后由 signal 中止观察者加入队列的工作会被锁存，并在被中止的活动收敛到空闲时执行——`disposed` 取消则将其停放（[取消收敛窗口唤醒锁存](../bug-fix/2026-08-07-cancel-convergence-wake-latch.md)）。若 `running` 监听器同步取消旧工作并发送替代提示词，驱动器会丢弃已中止的持有者，并为替代提示词创建全新的持有者。同一活跃持有者上的重复取消遵循首次请求优先，后续调用仍可清除新入队的待处理工作。
 
 显式事件签名传递单个 payload 对象：agent 作用域事件在 payload 中携带 `agent` 和 `signal`，`next` 位于最后；其余 seam 保持 `signal` 紧邻 waterfall（瀑布式事件）的最终 `next` 之前。`PreStepContext` 与 `RequestFailureContext` 已退役，其字段并入 `agent/pre-step` 与 `agent/request-error` 的 payload（[payload-object 事件](2026-08-06-agent-event-payload-objects.md)）。pre-step 进入决策、请求配置、请求错误恢复、模型生成、工具执行、审批、轮次停止以及 subagent 或工作流请求都会收到当前 signal。钩子桥接器也必须提供 `RunHookOptions.signal`，使轮次取消能够到达 Bash 执行器终止进程组并等待其退出的边界。`SystemPrompt.assemble()` 在 `AssembleContext` 中携带 `signal?: AbortSignal`，因为该对象是显式请求值，也可表示轮次之外不携带 signal 的组装。监听器可以配合该 signal 取消，但不得保留它来控制其他轮次。
 

.agents/notes/implemented/bug-fix/2026-08-07-cancel-convergence-wake-latch.i18n.yaml

@@ -0,0 +1,6 @@
+# Bilingual-pair consistency record (docs/i18n/README.md): the git blob hash of each
+# side as of the last confirmed-consistent state. Both languages carry equal authority;
+# after editing either side, bring the other along and re-record with:
+#   pnpm run verify-translation-pairing --write .agents/notes/implemented/bug-fix/2026-08-07-cancel-convergence-wake-latch.md
+2026-08-07-cancel-convergence-wake-latch.md: fe00c78bdfadac0cc6c9c173fd04256f77a22051
+2026-08-07-cancel-convergence-wake-latch.zh.md: f76ad360e2d8b70f76c6baf53e2fde963a80b6c4

.agents/notes/implemented/bug-fix/2026-08-07-cancel-convergence-wake-latch.md

@@ -0,0 +1,29 @@
+# Agent Note: Latch wake-ups that land in the cancel-convergence window
+
+Status: implemented
+
+English | [中文](2026-08-07-cancel-convergence-wake-latch.zh.md)
+
+## Problem
+
+`Agent.cancel(cause, { keepInbox: true })` returns immediately after firing the abort signal, but the active driver may not have converged to `idle` yet: LLM stream teardown, tool cancellation, and the `turn/end` append all unwind asynchronously after `abort()` returns. A waking send arriving in that window was placed into `next-turn` while `wakeDriver()` returned early on the still-`running` phase, and the exiting driver never replayed the wake — the message stayed parked until another waking send arrived. The same dropped-wake window existed around aborted `runMaintenance` activities. Several tests enshrined the parked behavior ("waits for another wakeup"); the bug broke both `session.cancel` and the `subagent.interrupt` composition path (issue #1838). The owning cancellation and send contracts are the [explicit turn cancellation](../architecture/2026-07-16-explicit-turn-cancellation.md) and [unified send](../architecture/2026-07-22-unified-send-and-coalesced-user-messages.md) decisions; the production `keepInbox` consumer is [web stop preserves queue](2026-07-31-web-stop-preserves-queue.md).
+
+## Decision
+
+The `running` phase carries a `wakeRequested` latch, mirroring the existing `maintenance` phase field. `wakeDriver()` latches whenever the current activity cannot deliver the wake — a maintenance task never reads the queue, and an aborted activity converges without restarting — while a live driver needs no latch because it claims queued work itself. The exiting activity replays the latch at its own convergence boundary (`kick`'s `finally` and `runMaintenance`'s `finally`): this placement guarantees `turn/end N` lands before the replayed driver opens `turn/start N+1`, and that `whenIdle()` sees the replayed driver through its `activityDone` loop. The replay sites run only while `inbox.hasPending`, so a latched wake removed from the inbox before convergence does not start an empty driver. A wake sent while the agent is already idle keeps its turn boundary even when its message is cleared before the driver claims — that `idle → running → idle` transition is an observable contract: the goal-session driver's pause/disarm fallback fires on the `idle` transition after a cancelled reservation (CI caught this when the guard was moved into `wakeDriver()` and suppressed the boundary). `cancel()` without `keepInbox` clears the latch together with the inbox.
+
+The `signal.aborted` discriminator is load-bearing: it separates pre-abort queued work — which `keepInbox` parks for a later wake (acceptance criterion 1) — from post-abort explicit wakes, which must run after convergence.
+
+## Alternatives considered
+
+**Have `cancel()` set the phase to `idle` immediately.** Rejected: the driver is still unwinding, so this overlaps two drivers. The replay lives in the old driver's `finally`, which then never runs — 14 of 83 tests failed, several deadlocked. Repairing it requires identity-based phase ownership plus a turn-open quiescence barrier, which is strictly more machinery and is the latch in disguise.
+
+**Latch unconditionally for every non-idle wake.** Rejected: pre-abort wakes would auto-start after a `keepInbox` cancel, violating acceptance criterion 1; the "parks queued work" test and the error-window steering test both failed.
+
+**Replay through a chained promise (`activityDone.then(...)`).** Rejected: the replay would run outside the activity's own settlement, so `whenIdle()`'s loop can resolve before the replayed driver starts; fixing that requires replacing `activityDone` at send time and depends on microtask reaction ordering — more fragile than a synchronous flag.
+
+**Wait for quiescence in the subagent adapter.** Rejected by the issue scope: the cancel/wake state machine owns the fix, not a consumer.
+
+## Consequences
+
+The `running` phase gains a `wakeRequested` field; `cancel()` without `keepInbox` clears it alongside the inbox, and a `disposed` cancel never latches, so a wake landing after disposal begins stays parked and `whenIdle()` does not wait on a full model turn over the session being torn down. A wake arriving in the sub-microtask gap between the driver's final `hasPending` check and its exit still parks — no latch fires because the phase is `running` and not aborted; closing that gap requires the unconditional latch and is deliberately out of scope. Between the aborted turn and the replayed driver, status transitions emit a transient `idle → running` pair. A waking send whose message is cleared before any driver claims it still opens an empty completed turn, preserving the observable wake boundary.

.agents/notes/implemented/bug-fix/2026-08-07-cancel-convergence-wake-latch.zh.md

@@ -0,0 +1,29 @@
+# Agent Note: 锁存取消收敛窗口内到达的唤醒请求
+
+Status: implemented
+
+[English](2026-08-07-cancel-convergence-wake-latch.md) | 中文
+
+## 问题
+
+`Agent.cancel(cause, { keepInbox: true })` 在触发 abort 信号后立即返回，但活动 driver 可能尚未收敛到 `idle`：LLM 流拆除、工具取消与 `turn/end` 落盘都会在 `abort()` 返回后异步展开。在该窗口内到达的唤醒 send 被放入 `next-turn`，而 `wakeDriver()` 对仍处于 `running` 的 phase 直接返回，退出的 driver 也从不重放这次唤醒——消息会一直停放到下一条唤醒 send 到达。被中止的 `runMaintenance` 活动周围也存在同样的唤醒丢失窗口。多个测试固化了停放行为（「等待下一次唤醒」）；该缺陷同时破坏了 `session.cancel` 与 `subagent.interrupt` 组合路径（issue #1838）。拥有取消与发送契约的既有决策是[显式轮次取消](../architecture/2026-07-16-explicit-turn-cancellation.md)与[统一发送](../architecture/2026-07-22-unified-send-and-coalesced-user-messages.md)；生产环境中的 `keepInbox` 消费方是[Web 停止保留队列](2026-07-31-web-stop-preserves-queue.md)。
+
+## 决策
+
+`running` phase 携带 `wakeRequested` 锁存，与既有的 `maintenance` phase 字段对称。`wakeDriver()` 在当前活动无法投递唤醒时锁存——maintenance 任务从不读取队列，被中止的活动收敛后不会重启——而存活的 driver 不需要锁存，因为它自己会认领排队的工作。退出中的活动在其自身收敛边界（`kick` 的 `finally` 与 `runMaintenance` 的 `finally`）重放锁存：这一位置保证 `turn/end N` 先于重放 driver 打开 `turn/start N+1` 落盘，并保证 `whenIdle()` 通过其 `activityDone` 循环看到重放 driver。两个重放点仅在 `inbox.hasPending` 时执行，因此收敛前被从 inbox 移除的锁存唤醒不会启动空 driver。而 agent 已处于 idle 时发送的唤醒，即使消息在 driver 认领前被清除，仍会打开自己的 turn 边界——这趟 `idle → running → idle` 转换是可观察契约：goal-session driver 的 pause/disarm 回退依赖取消预订后的 `idle` 转换触发（把守卫放进 `wakeDriver()` 后该边界被抑制，CI 发现了这一点）。不带 `keepInbox` 的 `cancel()` 会连同 inbox 一起清除锁存。
+
+`signal.aborted` 判别项是承重的：它区分「中断前已排队的工作」——`keepInbox` 将其停放以待后续唤醒（验收条件 1）——与「abort 后显式的唤醒」，后者必须在收敛后执行。
+
+## 备选方案
+
+**让 `cancel()` 立即把 phase 置为 `idle`。** 不予采用：driver 仍在展开收尾，这会重叠两个 driver。重放逻辑位于旧 driver 的 `finally`，而该 `finally` 此后不再执行——83 个测试中有 14 个失败，多个死锁。修复它需要基于身份的 phase 所有权外加 turn 打开时的 quiescence 屏障，机制上严格更重，而且该屏障就是换了个形态的锁存。
+
+**对每个非 idle 唤醒无条件锁存。** 不予采用：中断前的唤醒会在 `keepInbox` 取消后自动启动，违反验收条件 1；「停放排队工作」测试与错误窗口的 steering 测试双双失败。
+
+**通过链式 promise（`activityDone.then(...)`）重放。** 不予采用：重放会运行在活动自身结算之外，`whenIdle()` 的循环可能在重放 driver 启动前就 resolve；修复它需要在 send 时同步替换 `activityDone`，并依赖微任务反应顺序——比同步 flag 更脆弱。
+
+**在 subagent adapter 中等待 quiescence。** 被 issue 范围否决：修复由取消/唤醒状态机拥有，而不是消费方。
+
+## 影响
+
+`running` phase 新增 `wakeRequested` 字段；不带 `keepInbox` 的 `cancel()` 会连同 inbox 一起清除它，且 `disposed` 取消从不锁存——dispose 开始后到达的唤醒保持停放，`whenIdle()` 不会在拆除中的会话上等待一个完整模型 turn。落在 driver 最后一次 `hasPending` 检查与退出之间微任务间隙的唤醒仍会停放——没有锁存触发，因为 phase 是 `running` 且未 abort；关闭该间隙需要无条件锁存，刻意留作范围外。在被中止的 turn 与重放 driver 之间，状态转换会发出一次瞬态 `idle → running` 对。唤醒 send 的消息在任何 driver 认领前被清除时，仍会打开一个空的 completed turn，保留可观察的唤醒边界。