Effect-owned TUI interactive extensions
由 effect 持有的 TUI 交互扩展
Cordis plugins can register human commands through `ctx.commands`, but a command that needs terminal interaction has no supported presentation boundary. It must either remain non-interactive or capture the TUI's private pi-tui tree, focus state, renderer, and shutdown lifecycle. That coupling makes the extension depend on one front door's internals, lets independently developed overlays compete for focus, and leaves
English
Problem
Cordis plugins can register human commands through ctx.commands, but a command that needs terminal interaction has no supported presentation boundary. It must either remain non-interactive or capture the TUI's private pi-tui tree, focus state, renderer, and shutdown lifecycle. That coupling makes the extension depend on one front door's internals, lets independently developed overlays compete for focus, and leaves plugin unload with no reliable way to remove queued or visible UI.
Decision
A mounted @deepseek-ai/dsh-tui provides ctx.tui after terminal startup succeeds. The service belongs to that exact terminal and agent, disappears before terminal teardown, and causes plugins that inject it to unload and reload with provider availability. Other front doors do not emulate it.
ctx.tui.openOverlay() is the first and only interactive extension primitive. It accepts a component factory, constrained layout options, and an optional abort signal. The factory receives a frozen host with the current viewport, semantic theme functions, display-text escaping, redraw, close, and a lifetime signal. It does not receive the pi-tui TUI, overlay handle, editor, transcript tree, focus controller, or terminal object.
One private overlay manager serializes built-in and plugin requests in FIFO order. The model selector and ctx.userInteraction question panel use the same manager, so all modal interaction has one focus owner. Closing the active overlay restores pi-tui's previous focus before the next request activates. Overlay state is process-local presentation: it is neither appended to the session log nor rebuilt during resume.
The service method runs through Cordis's traceable service proxy. It installs an effect on the calling plugin fiber before admitting the request; caller disposal therefore removes a queued request or closes an active overlay and awaits the same settled outcome. TUI shutdown first rejects admission, then disposes the service fiber so dependent plugins and their effects quiesce, settles remaining built-in work, and only then drains and stops the terminal.
Component construction, rendering, input, and invalidation run behind an exception boundary. A failure closes that request with an error outcome, reports a visible terminal error, and lets the queue continue. Components are trusted package code: their rendered lines may contain ANSI styling, and they must call host.display() before including untrusted text.
Verification
Manager tests pin FIFO admission, cancellation, repeated close, shutdown outcomes, guarded callbacks, host capabilities, and per-file coverage. Cordis lifecycle tests pin caller ownership, provider loss and return, unloading-time rejection, and cleanup quiescence. Fake-terminal integration tests exercise plugin overlays alongside built-in questions, restored editor input, terminal remount, startup rollback, and service disappearance. Existing TUI interaction tests continue to exercise the model selector and question panel through the shared path.
Alternatives considered
Expose pi-tui objects directly. This gives plugins maximum freedom but makes private focus, rendering, and teardown state a public compatibility contract. It also cannot arbitrate independently loaded overlays.
Put interactive callbacks on command definitions. Commands remain transport-neutral domain entries even though TUI is their only shipped consumer. Adding terminal state to ctx.commands would couple discovery and dispatch to one presentation implementation.
Create a complete TUI slot and action framework at once. Actions, editor replacement, transcript renderers, status regions, and completion providers have different composition and conflict rules. Shipping them behind one broad API would freeze those rules before a concrete consumer proves them.
Persist open overlays in session events. Modal presentation is not model-visible session state, and arbitrary component state is not replayable. The plugin that owns durable data records that data through its domain service and recreates presentation when appropriate.
Consequences
Interactive plugins gain a small stable front door with deterministic focus and Cordis-owned cleanup, while the TUI keeps authority over terminal lifecycle and pi-tui internals. Built-in dialogs and extensions cannot overlap or strand focus.
The API deliberately covers modal overlays only. Human command registration remains on ctx.commands; actions, slots, editor replacement, event renderers, and completion providers require separate contracts when real consumers establish their ordering and ownership semantics. FIFO serialization also means one stalled overlay blocks later modal work until its owner closes, aborts, or unloads it.
中文
问题
Cordis 插件可以通过 ctx.commands 注册用户命令，但需要终端交互的命令没有受支持的呈现边界。它只能保持非交互，或者捕获 TUI 私有的 pi-tui 树、焦点状态、渲染器和关闭生命周期。此类耦合会使扩展依赖某个入口的内部实现，让各自独立开发的浮层争抢焦点，并导致插件卸载时无法可靠移除排队中或已显示的 UI。
决策
挂载的 @deepseek-ai/dsh-tui 在终端成功启动后提供 ctx.tui。该服务只属于挂载时绑定的终端与 agent（智能体），在终端拆卸前消失，并使注入它的插件随着提供方的可用与否卸载和重新加载。其他入口不会模拟该服务。
ctx.tui.openOverlay() 是第一个也是唯一一个交互扩展原语。它接受组件工厂、受限的布局选项，以及可选的中止信号。工厂收到一个冻结的 host，其中包含当前视口、语义化主题函数、显示文本转义、重绘、关闭和生命周期信号。它不会收到 pi-tui TUI、浮层句柄、编辑器、transcript（文本记录）树、焦点控制器或终端对象。
一个私有浮层管理器按 FIFO 顺序串行处理内置请求和插件请求。模型选择器与 ctx.userInteraction 问题面板使用同一个管理器，因此所有模态交互只有一个焦点所有者。关闭活动浮层时，系统会先恢复 pi-tui 之前的焦点，再激活下一项请求。浮层状态是进程本地的呈现状态：它既不会追加到会话日志，也不会在恢复期间重建。
服务方法通过 Cordis 的可追踪服务代理运行。它在接纳请求前，向调用方插件的 fiber 注册一个 effect；因此，调用方执行 dispose（资源释放）时会移除排队中的请求或关闭活动浮层，并等待同一个结果完成结算。TUI 关闭时会先拒绝新请求，再 dispose 服务 fiber，让依赖插件及其 effect 完全静止，然后结算其余内置工作，最后才排空并停止终端。
组件构造、渲染、输入与失效处理均在异常边界内运行。任何失败都会以 error 结果关闭对应请求、在终端中报告一条可见错误，并让队列继续处理。组件属于受信任的包代码：其渲染行可以包含 ANSI 样式，但加入不受信任的文本前必须调用 host.display()。
验证
管理器测试固定了 FIFO 准入、取消、重复关闭、关闭结果、受保护回调、host 能力和逐文件覆盖率。Cordis 生命周期测试固定了调用方所有权、提供方消失与恢复、卸载期间的拒绝，以及清理达到完全静止。模拟终端集成测试覆盖插件浮层与内置问题的协作、编辑器输入焦点恢复、终端重新挂载、启动回滚和服务消失。既有 TUI 交互测试继续通过共享路径覆盖模型选择器与问题面板。
考虑过的替代方案
直接暴露 pi-tui 对象。 这会赋予插件最大的自由度，却会把私有的焦点、渲染与拆卸状态变成公开兼容性契约，也无法在独立加载的浮层之间进行仲裁。
在命令定义中加入交互回调。 命令仍是传输无关的领域条目，尽管 TUI 是唯一已交付的消费方。向 ctx.commands 添加终端状态，会让发现与分派流程耦合到某一种呈现实现。
一次性建立完整的 TUI slot 与 action 框架。 action、编辑器替换、transcript 渲染器、状态区域和补全提供方具有不同的组合规则与冲突规则。在具体消费方验证这些规则之前就将其纳入一个宽泛 API，会过早固化这些规则。
将打开的浮层持久化为会话事件。 模态呈现并非模型可见的会话状态，任意组件状态也无法回放。拥有持久数据的插件应通过自身的领域服务记录这些数据，并在适当时重新创建呈现。
后果
交互式插件获得一个小而稳定的入口，具备确定性的焦点管理和由 Cordis 持有的清理机制；TUI 则继续掌控终端生命周期和 pi-tui 内部实现。内置对话框与扩展无法重叠，也不会遗留失去归属的焦点。
该 API 有意只覆盖模态浮层。用户命令仍然在 ctx.commands 上注册；action、slot、编辑器替换、事件渲染器和补全提供方需要另行设计契约，等待实际消费方确定其顺序与所有权语义。FIFO 串行处理也意味着，一个停滞的浮层会阻塞后续模态工作，直至其所有者关闭、中止或卸载该浮层。