持久 PTY 会话
PTY 后端、ctx.terminals 与面向模型的消费方共享的类型。持久 PTY Agent Note 负责记录决策依据；本页记录来自 packages/terminal/terminal/src/types.ts 的跨包词汇。
标识与就绪
TerminalSessionId 是由服务铸造的branded id。可选名称是拥有者本地的显示元数据；授权比较的是拥有该会话的确切 Agent，而不是名称或猜测的 id。
TerminalWaitReason 说明一次发送为何返回。它与 TerminalSessionStatus 无关：一次发送可能因静默或超时而返回，但顶层 shell 仍然存活；session_exit 表示该 shell 已退出，而不是某个任意的前台子进程已退出。
ts
/** Why one interactive send returned control to its caller. */
type TerminalWaitReason = 'stdin_read' | 'inferred_idle' | 'timeout' | 'session_exit'ts
/** Top-level PTY process status, independent of a send's wait reason. */
type TerminalSessionStatus =
| { kind: 'running' }
| { kind: 'exited'; exitCode: number | null; signal: NodeJS.Signals | null }后端与活跃会话
后端负责启动某种已注册类型的会话并检测其就绪状态。TerminalSessionService 只在初始化成功后才发布返回的会话，随后负责 id 授权与清理。无法清理部分启动资源时，后端会以 TerminalBackendCleanupError 拒绝启动；这样，资源释放流程既能保留清理失败，也不会用它替换调用方的取消原因。后端会话拥有终端状态，并负责让已捕获的资源完全停稳。
ts
/** Replaceable provider for one PTY session type. */
interface TerminalBackend {
/** Stable type selected by {@link TerminalSpawnRequest.type}. */
readonly type: string
/** Create an unpublished session or reject after cleaning partial resources; cleanup failure uses {@link TerminalBackendCleanupError}. */
spawn(spec: TerminalBackendSpawnSpec): Promise<TerminalBackendSession>
}ts
/** Backend-owned live session retained by {@link TerminalSessionService}. */
interface TerminalBackendSession {
/** Initial bounded terminal output returned from `terminal_open`. */
readonly motd: string
/** Top-level process id when one exists. */
readonly pid?: number
/** Start one exclusive send operation. */
startSend(request: TerminalSendRequest): TerminalSendOperation
/** Read one bounded page from retained scrollback. */
read(request: TerminalReadRequest): TerminalReadResult
/** Signal the verified foreground process group. */
signal(signal: TerminalSignal): Promise<TerminalSignalResult>
/** Observe top-level process status. */
status(): TerminalSessionStatus
/** Idempotently close the captured owned process tree and await quiescence. */
close(reason: string): Promise<void>
}发送与保留输出
一个活跃会话同时只接受一个活动发送。该操作向通用后台任务提供读取后即推进的输出游标，并向前台调用方提供最终结果。TerminalReadResult 则为有界的会话 scrollback 单独分页。
ts
/** Live backend-owned send; exactly one may be active per PTY session. */
interface TerminalSendOperation {
/** Resolves after readiness, timeout, cancellation, or top-level process exit. */
done: Promise<TerminalSendResult>
/** Consume output produced since the prior call. */
readOutput(): TerminalSendRead
/** Request `SIGINT`; returns false after the operation settled. */
cancel(): boolean
}ts
/** Settled result for one foreground or background send. */
interface TerminalSendResult {
/** Bounded rendered terminal delta remaining at settlement. */
viewport: string
/** Why the wait returned; this does not imply arbitrary child-process exit. */
waitReason: TerminalWaitReason
/** Top-level session status observed at settlement. */
sessionStatus: TerminalSessionStatus
/** Whether output was dropped from the operation or retained scrollback. */
truncated: boolean
}归属与持久性
TerminalSessionService 会将一项等待完成的清理附加到确切的拥有者作用域，拒绝其他拥有者的操作，并让会话在后端或工具插件重载期间保持存活。PTY 状态与原始字节仍局限在进程内。模型输入与有界返回输出通过现有 tool/call、tool/result 和任务结果路径持久保存，而不是重复记录 PTY 会话事件。
Cordis API
Generated from source by scripts/gen-cordis-catalog.ts (verified fresh by pnpm run verify-cordis-catalog in doc-sync; regenerate with pnpm run gen-cordis-catalog) — this section is byte-identical in both language sides of the page. Signature blocks use a ts cordis-catalog fence and keep the original source JSDoc; dispatch modes are defined in the primer, and the framework-inherited ctx API lives in cordis-api/inherited.md.
ctx.terminals — TerminalSessionService
In-process registry for replaceable PTY backends and exact-Agent sessions.
ts
/**
* Register one backend type for this effect scope.
* @param backend - provider with a non-empty unique type.
* @returns disposer that removes exactly this contribution.
*/
registerBackend(backend: TerminalBackend): () => void
/**
* List registered backend types in registration order.
* @returns fresh backend type names.
*/
listBackends(): string[]
/**
* Create and publish one owner-scoped session after backend setup succeeds.
* @param owner - exact registered Agent that owns access and cleanup.
* @param request - backend type plus optional owner-local name and cwd.
* @param signal - cancellation of unpublished setup.
* @returns published identity, metadata, status, and MOTD.
*/
async spawn(owner: Agent, request: TerminalSpawnRequest, signal?: AbortSignal): Promise<TerminalSpawnResult>
/**
* Test whether an exact owner has a published session or unpublished spawn.
* @param owner - exact live owner to inspect.
* @returns true across the entire spawn-to-close interval, with no publication gap.
*/
hasOwnerActivity(owner: Agent): boolean
/**
* Start one exclusive interactive send.
* @param owner - exact session owner.
* @param id - target PTY identity.
* @param request - explicit text, submit behavior, and cancellation.
* @returns live operation handle for foreground await or task registration.
*/
startSend(owner: Agent, id: TerminalSessionId, request: TerminalSendRequest): TerminalSendOperation
/**
* Read one bounded scrollback page from an owned session.
* @param owner - exact session owner.
* @param id - target PTY identity.
* @param request - optional newest-relative offset and line count.
* @returns bounded retained text and pagination metadata.
*/
read(owner: Agent, id: TerminalSessionId, request: TerminalReadRequest = {}): TerminalReadResult
/**
* Deliver an allowed signal through an owned backend session.
* @param owner - exact session owner.
* @param id - target PTY identity.
* @param signal - allowed POSIX signal name.
* @returns delivered foreground process-group identity.
*/
signal(owner: Agent, id: TerminalSessionId, signal: TerminalSignal): Promise<TerminalSignalResult>
/**
* Close one owned session and remove it only after quiescent backend cleanup.
* @param owner - exact session owner.
* @param id - target PTY identity.
* @param reason - diagnostic cleanup reason.
* @returns true for a newly closed session, false when the same close is already in flight.
*/
async kill(owner: Agent, id: TerminalSessionId, reason: string = 'model request'): Promise<boolean>
/**
* List fresh snapshots for exactly one owner.
* @param owner - exact owner whose sessions are visible.
* @returns owner-visible snapshots in publication order.
*/
list(owner: Agent): TerminalSessionSnapshot[]Types: Agent