diff --git a/.agents/notes/implemented/simplification/2026-07-21-tui-remove-cancel-command.i18n.yaml b/.agents/notes/implemented/simplification/2026-07-21-tui-remove-cancel-command.i18n.yaml
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+# 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
+2026-07-21-tui-remove-cancel-command.md: f9bad74e7b8f04a162a32e8045d2f874991b9d5d
+2026-07-21-tui-remove-cancel-command.zh.md: 6a4c0af1d2ac345afd775566db21f7a7c0b262da
diff --git a/.agents/notes/implemented/simplification/2026-07-21-tui-remove-cancel-command.md b/.agents/notes/implemented/simplification/2026-07-21-tui-remove-cancel-command.md
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+# Agent Note: Drop the TUI `/cancel` slash command
+
+Status: implemented
+
+English | [中文](2026-07-21-tui-remove-cancel-command.zh.md)
+
+## Problem
+
+The TUI exposed two identical ways to cancel a running turn: the `Esc` (and `Ctrl+C`) keybinding and a `/cancel` slash command. Both called `agent.cancel('cancelled from terminal')` with the same reason; when idle, `/cancel` only printed a "The agent is already idle." notice while the keybindings stayed silent. The running status line already advertises the keybinding (`Enter sends steering, Esc cancels`), and cancelling by keystroke needs no editor submission, so the slash command was a second, less discoverable path to the same effect — surface area with no behavior of its own.
+
+## Decision
+
+`/cancel` is removed. Cancelling a running turn is a keybinding-only affordance (`Esc`, or `Ctrl+C` while running), which the status-line hint and the `/help` shortcut list already document. The `baseCommands` autocomplete entry, the `/help` command line, the `case '/cancel'` branch in the editor submit handler, and the "already idle" notice it owned are gone; every other slash command (`/help`, `/clear`, `/reasoning`, `/tools`, `/redraw`, `/reload`, `/resume`, `/exit`, `/skill:<name>`) is unchanged. Typing `/cancel` now falls through to the generic `Unknown command:` warning like any other unrecognized slash input.
+
+## Alternatives considered
+
+**Keep `/cancel` as a discoverability alias** — rejected: the running status line and `/help` both name `Esc`, so a typed alias adds a maintained code path and a per-idle-state notice for an action a single keystroke already performs more directly. No consumer needed the editor-submission route to cancellation.
+
+## Testing
+
+`packages/ui/tui/tests/tui.spec.ts` asserts `agent.cancelled` contains `'cancelled from terminal'`, driven by the `Esc`/`Ctrl+C` keystrokes in that turn — the sole cancel affordance. The `errors-and-help` and `disposed-terminal` snapshots pin the `/help` line without `/cancel`; per-file coverage on `packages/ui/tui/src` stays at 100%.
+
+## Consequences
+
+There is no way to cancel a turn by editor submission; cancellation is keybinding-only. This is a net removal of a redundant path and its idle-state notice, matching the single-primitive shape the rest of the stop surface already follows ([public stop surface](2026-06-20-public-agent-stop-surface.md)). Restoring a typed cancel would return with the autocomplete entry, the submit-handler branch, and its own test.
diff --git a/.agents/notes/implemented/simplification/2026-07-21-tui-remove-cancel-command.zh.md b/.agents/notes/implemented/simplification/2026-07-21-tui-remove-cancel-command.zh.md
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+# Agent Note: Drop the TUI `/cancel` slash command
+
+Status: implemented
+
+[English](2026-07-21-tui-remove-cancel-command.md) | 中文
+
+## Problem
+
+TUI 提供了两条完全相同的取消运行中轮次的方式：`Esc`（以及 `Ctrl+C`）键位绑定，和一条 `/cancel` 斜杠命令。两者都以相同的原因调用 `agent.cancel('cancelled from terminal')`；空闲时 `/cancel` 只打印一条 "The agent is already idle." 通知，而键位绑定保持静默。运行状态行本就标示了该键位绑定（`Enter sends steering, Esc cancels`），且按键取消无需提交编辑器，因此这条斜杠命令只是通往同一效果的第二条、且更难被发现的路径——一块本身不含任何行为的界面。
+
+## Decision
+
+`/cancel` 已移除。取消运行中的轮次是一项仅由键位绑定提供的能力（`Esc`，或运行中的 `Ctrl+C`），状态行提示与 `/help` 快捷键清单已对其作出说明。`baseCommands` 自动补全条目、`/help` 命令行、编辑器提交处理函数中的 `case '/cancel'` 分支，以及它拥有的 "already idle" 通知都已删去；其余每一条斜杠命令（`/help`、`/clear`、`/reasoning`、`/tools`、`/redraw`、`/reload`、`/resume`、`/exit`、`/skill:<name>`）保持不变。键入 `/cancel` 会像任何其他无法识别的斜杠输入一样，落入通用的 `Unknown command:` 警告。
+
+## Alternatives considered
+
+**保留 `/cancel` 作为便于发现的别名。** 否决：运行状态行与 `/help` 都已标示 `Esc`，因此一个键入式别名会为一项单个按键已能更直接完成的操作，增加一条需维护的代码路径和一条逐空闲状态的通知。没有任何消费方需要经由编辑器提交来触发取消。
+
+## Testing
+
+`packages/ui/tui/tests/tui.spec.ts` 断言 `agent.cancelled` 包含 `'cancelled from terminal'`，由该轮次中的 `Esc`/`Ctrl+C` 按键驱动——这是唯一的取消能力。`errors-and-help` 与 `disposed-terminal` 快照固定了不含 `/cancel` 的 `/help` 行；`packages/ui/tui/src` 的逐文件覆盖率维持在 100%。
+
+## Consequences
+
+无法再经由编辑器提交取消一个轮次；取消仅由键位绑定提供。这是对一条冗余路径及其空闲状态通知的净移除，与其余停止能力已遵循的单一原语形态一致（[public stop surface](2026-06-20-public-agent-stop-surface.md)）。若要恢复键入式取消，需连同自动补全条目、提交处理函数分支及其专属测试一并回归。