Merge branch 'master' into feat/subagent-process

2026-07-09 22:19:30 +08:00
parent 0ba6d832f8 137530954a
commit 88ab5ce0bc
51 changed files with 2058 additions and 32 deletions
--- a/docs/capability-seams.md
+++ b/docs/capability-seams.md
@@ -30,11 +30,14 @@ flowchart LR
  pkg_tool_fs["tool-fs"]
  pkg_tool_web["tool-web"]
  svc_tools["ctx.tools<br/>Tool registry and execution waterfall"]
+  pkg_tool_ask_user["tool-ask-user"]
  pkg_tool_bash["tool-bash"]
  pkg_tool_subagent["tool-subagent"]
  pkg_tool_todo["tool-todo"]
-  svc_agents["ctx.agents<br/>Agent registry"]
+  pkg_user_interaction["user-interaction"]
+  svc_userInteraction["ctx.userInteraction<br/>Human question/answer seam"]
  pkg_stdio_agent["stdio-agent"]
+  svc_agents["ctx.agents<br/>Agent registry"]
  svc_agentLoop["ctx.agentLoop<br/>Concrete loop driver"]
  pkg_agent_core["agent-core"]
  pkg_bash["bash"]
@@ -63,6 +66,7 @@ flowchart LR
  pkg_web_search_perplexity["web-search-perplexity"]
  pkg_web_search_deepseek["web-search-deepseek"]
  pkg_web_fetch_local["web-fetch-local"]
+  pkg_acp --> svc_userInteraction
  pkg_agent --> svc_agents
  pkg_agent_loop --> svc_agentLoop
  pkg_bash --> svc_bash
@@ -81,6 +85,7 @@ flowchart LR
  pkg_session_persistence --> svc_sessionPersistence
  pkg_session_persistence_jsonl --> svc_sessionPersistence
  pkg_session_persistence_sqlite --> svc_sessionPersistence
+  pkg_stdio_agent --> svc_userInteraction
  pkg_subagent --> svc_subagents
  pkg_subagent_acp --> svc_subagents
  pkg_subagent_fork --> svc_subagents
@@ -88,6 +93,7 @@ flowchart LR
  pkg_subagent_spawn --> svc_subagents
  pkg_system_prompt --> svc_systemPrompt
  pkg_tools --> svc_tools
+  pkg_user_interaction --> svc_userInteraction
  pkg_web --> svc_web
  pkg_web_fetch_local --> svc_web
  pkg_web_search_deepseek --> svc_web
@@ -120,11 +126,15 @@ flowchart LR
  svc_systemPrompt --> pkg_tools
  svc_tools --> pkg_acp
  svc_tools --> pkg_agent_loop
+  svc_tools --> pkg_tool_ask_user
  svc_tools --> pkg_tool_bash
  svc_tools --> pkg_tool_fs
  svc_tools --> pkg_tool_subagent
  svc_tools --> pkg_tool_todo
  svc_tools --> pkg_tool_web
+  svc_userInteraction --> pkg_acp
+  svc_userInteraction --> pkg_stdio_agent
+  svc_userInteraction --> pkg_tool_ask_user
  svc_web --> pkg_tool_web
  svc_fs -. event gate .-> pkg_fs_policy
 ```
@@ -135,7 +145,8 @@ flowchart LR
 | `ctx.sessions` | `core` | [`session`](../packages/core/session) | - | [`agent-loop`](../packages/core/agent-loop), [`agent`](../packages/core/agent), [`session-persistence`](../packages/session-persistence/session-persistence), [`subagent-inprocess`](../packages/subagent/subagent-inprocess), [`invariants`](../packages/support/invariants) | - | Owns append-only Session instances and emits the durable session event feed. |
 | `ctx.sessionPersistence` | `seam` | [`session-persistence`](../packages/session-persistence/session-persistence) | [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`session-persistence-sqlite`](../packages/session-persistence/session-persistence-sqlite) | [`agent-loop`](../packages/core/agent-loop), [`acp`](../packages/ui/acp) | - | Backends persist the same SessionEvent vocabulary; apps choose a backend at composition time. |
 | `ctx.systemPrompt` | `core` | [`system-prompt`](../packages/core/system-prompt) | - | [`agent-loop`](../packages/core/agent-loop), [`tools`](../packages/core/tools), [`tool-fs`](../packages/fs/tool-fs), [`tool-web`](../packages/web/tool-web) | - | Collects prompt sections and model-facing tool schemas for each step. |
-| `ctx.tools` | `core` | [`tools`](../packages/core/tools) | - | [`agent-loop`](../packages/core/agent-loop), [`tool-bash`](../packages/bash/tool-bash), [`tool-fs`](../packages/fs/tool-fs), [`tool-subagent`](../packages/subagent/tool-subagent), [`tool-todo`](../packages/todo/tool-todo), [`tool-web`](../packages/web/tool-web), [`acp`](../packages/ui/acp) | - | Registers tool definitions, exposes schemas to the prompt, and routes calls through tools/pre-execute and tools/post-execute. |
+| `ctx.tools` | `core` | [`tools`](../packages/core/tools) | - | [`agent-loop`](../packages/core/agent-loop), [`tool-ask-user`](../packages/ui/tool-ask-user), [`tool-bash`](../packages/bash/tool-bash), [`tool-fs`](../packages/fs/tool-fs), [`tool-subagent`](../packages/subagent/tool-subagent), [`tool-todo`](../packages/todo/tool-todo), [`tool-web`](../packages/web/tool-web), [`acp`](../packages/ui/acp) | - | Registers tool definitions, exposes schemas to the prompt, and routes calls through tools/pre-execute and tools/post-execute. |
+| `ctx.userInteraction` | `seam` | [`user-interaction`](../packages/ui/user-interaction) | [`stdio-agent`](../packages/ui/stdio-agent), [`acp`](../packages/ui/acp) | [`tool-ask-user`](../packages/ui/tool-ask-user), [`stdio-agent`](../packages/ui/stdio-agent), [`acp`](../packages/ui/acp) | - | UI front doors provide the active human-answer provider; tool-ask-user pauses a tool call on the provider-neutral ask() promise. |
 | `ctx.agents` | `core` | [`agent`](../packages/core/agent) | - | [`agent-loop`](../packages/core/agent-loop), [`acp`](../packages/ui/acp), [`subagent-inprocess`](../packages/subagent/subagent-inprocess), [`stdio-agent`](../packages/ui/stdio-agent), [`invariants`](../packages/support/invariants) | - | Owns live Agent handles and the create/resume factory seam. |
 | `ctx.agentLoop` | `bundle` | [`agent-loop`](../packages/core/agent-loop) | - | [`agent-core`](../packages/core/agent-core) | - | The one concrete loop plugin; extension packages depend on dsh-agent events and services, not on this package. |
 | `ctx.bash` | `seam` | [`bash`](../packages/bash/bash) | [`bash-local`](../packages/bash/bash-local) | [`tool-bash`](../packages/bash/tool-bash), [`hooks-claude`](../packages/hooks/hooks-claude), [`hooks-codex`](../packages/hooks/hooks-codex) | - | The model-facing bash tools and hook bridges consume this seam; sandboxed or remote executors can replace bash-local. |
--- a/docs/config-catalog.md
+++ b/docs/config-catalog.md
@@ -11,7 +11,7 @@ A `Requires:` line lists the service keys the plugin `inject`s: its `cordis.yml`

 ## `@deepseek-ai/dsh-acp`

-Requires: `agents` · `sessions` · `sessionPersistence` · `tools`
+Requires: `agents` · `sessions` · `sessionPersistence` · `tools` · `userInteraction`

 ```ts config-catalog
 /** Plugin config: the agent template ACP sessions are created from. */
@@ -31,7 +31,7 @@ export interface AcpConfig {

 Depends on: `Stream` (`@agentclientprotocol/sdk`)

-Source: [`packages/ui/acp/src/index.ts:115`](../packages/ui/acp/src/index.ts)
+Source: [`packages/ui/acp/src/index.ts:236`](../packages/ui/acp/src/index.ts)

 ## `@deepseek-ai/dsh-acp-agent`

@@ -56,7 +56,7 @@ export interface Config {
 }
 ```

-Source: [`packages/ui/acp-agent/src/index.ts:49`](../packages/ui/acp-agent/src/index.ts)
+Source: [`packages/ui/acp-agent/src/index.ts:50`](../packages/ui/acp-agent/src/index.ts)

 ## `@deepseek-ai/dsh-agent-core`

@@ -505,7 +505,7 @@ export interface Config {
 }
 ```

-Source: [`packages/ui/stdio-agent/src/index.ts:60`](../packages/ui/stdio-agent/src/index.ts)
+Source: [`packages/ui/stdio-agent/src/index.ts:62`](../packages/ui/stdio-agent/src/index.ts)

 ## `@deepseek-ai/dsh-subagent-acp`

@@ -866,9 +866,11 @@ These load from a `cordis.yml` entry with no `config:` block; they declare no co
 - `@deepseek-ai/dsh-session` ([`packages/core/session/src/index.ts`](../packages/core/session/src/index.ts))
 - `@deepseek-ai/dsh-subagent` ([`packages/subagent/subagent/src/index.ts`](../packages/subagent/subagent/src/index.ts))
 - `@deepseek-ai/dsh-timeout-policy` — requires `tools` ([`packages/timeout/timeout-policy/src/index.ts`](../packages/timeout/timeout-policy/src/index.ts))
+- `@deepseek-ai/dsh-tool-ask-user` — requires `tools` · `userInteraction` ([`packages/ui/tool-ask-user/src/index.ts`](../packages/ui/tool-ask-user/src/index.ts))
 - `@deepseek-ai/dsh-tool-bash` — requires `tools` · `bash` · `systemPrompt` ([`packages/bash/tool-bash/src/index.ts`](../packages/bash/tool-bash/src/index.ts))
 - `@deepseek-ai/dsh-tool-todo` — requires `tools` ([`packages/todo/tool-todo/src/index.ts`](../packages/todo/tool-todo/src/index.ts))
 - `@deepseek-ai/dsh-tools` — requires `systemPrompt` ([`packages/core/tools/src/index.ts`](../packages/core/tools/src/index.ts))
+- `@deepseek-ai/dsh-user-interaction` ([`packages/ui/user-interaction/src/index.ts`](../packages/ui/user-interaction/src/index.ts))

 ## Seam packages (not directly loadable)

--- a/docs/cordis-catalog/services.md
+++ b/docs/cordis-catalog/services.md
@@ -226,6 +226,17 @@ Types: [ToolDefinition](../core-data-structures/tools.md) · [ToolExecution](../

 Source: [`packages/core/tools/src/index.ts:307`](../../packages/core/tools/src/index.ts)

+## `ctx.userInteraction` — `UserInteractionService`
+
+`ctx.userInteraction`: one active UI provider plus an `ask()` surface.
+
+```ts cordis-catalog
+registerProvider(provider: UserInteractionProvider): () => void
+async ask(request: AskUserQuestionRequest): Promise<AskUserQuestionAnswer>
+```
+
+Source: [`packages/ui/user-interaction/src/index.ts:82`](../../packages/ui/user-interaction/src/index.ts)
+
 ## `ctx.web` — `WebService`

 The web access service. Registered as `ctx.web` (one instance per context).
--- a/docs/core-data-structures/core.md
+++ b/docs/core-data-structures/core.md
@@ -19,6 +19,7 @@ Everything else is documented on a **sub-page**, not here. The rule that draws t
 | [session.md](session.md) | the full `SessionEventMap` variant catalog, `TurnTrigger`/`TurnEndReason`, `deriveMessages()`, the turn-enclosure invariant |
 | [persistence.md](persistence.md) | the durability seam: `SessionPersistence`, JSONL + SQLite backends, `session/flush`, crash recovery, `SessionHeader` |
 | [tools.md](tools.md) | `ToolDefinition` full fields, the schema DSL, `ToolExecution`/`ToolResult`, tool-presentation UI types, the `tools/pre-execute`/`tools/post-execute` pipeline |
+| [user-interaction.md](user-interaction.md) | the UI-backed human question/answer seam: `AskUserQuestionRequest`, answer/options vocabulary, provider API, error taxonomy |
 | [bash.md](bash.md) | the bash executor seam: `BashExecRequest`/`Spec`, `BashRunResult`, background `BashTask`s |
 | [code-runtime.md](code-runtime.md) | the code-execution seam: `CodeRunRequest`/`Result`, binding namespaces, captured logs, the `CodeRunFailure` taxonomy |
 | [filesystem.md](filesystem.md) | the filesystem seam: `FsTarget`, read/write/edit outcomes, observed-file state, `FsErrorCode` |
--- a/docs/core-data-structures/user-interaction.md
+++ b/docs/core-data-structures/user-interaction.md
@@ -0,0 +1,97 @@
+# User Interaction
+
+The user-interaction seam of [dsh-user-interaction](../../packages/ui/user-interaction). It is the provider-neutral vocabulary a tool or permission plugin uses when it needs the human to answer before the agent can continue. UI surfaces provide the active `UserInteractionProvider`: `dsh-stdio-agent` renders questions in readline, and `dsh-acp` maps them to ACP form elicitations.
+
+Source: [`packages/ui/user-interaction/src/index.ts`](../../packages/ui/user-interaction/src/index.ts)
+
+## Question options
+
+`AskUserQuestionOption` is the selectable-choice shape. `label` is the user-facing option text and also the model-facing selected value; `description` is optional UI help text.
+
+```ts type-equiv
+interface AskUserQuestionOption {
+  /** User-facing label. */
+  label: string
+  /** Optional extra context rendered by capable UIs. */
+  description?: string
+}
+```
+
+## Question item
+
+`AskUserQuestionItem` is one question in a request. The model supplies a stable `id`, which is echoed back with the answer so batched questions remain routable.
+
+```ts type-equiv
+interface AskUserQuestionItem {
+  /** Stable model-provided question id, echoed in the answer. */
+  id: string
+  /** The question to display. */
+  question: string
+  /** Optional short heading/group label. */
+  header?: string
+  /** Optional choices the UI can render as a menu. */
+  options?: AskUserQuestionOption[]
+  /** Whether more than one option may be selected. Defaults to single-select. */
+  multiSelect?: boolean
+}
+```
+
+## Ask request
+
+`AskUserQuestionRequest` is the cross-package request. `questions` is an array so a UI can present related prompts in one flow while preserving a stable id per answer.
+
+```ts type-equiv
+interface AskUserQuestionRequest {
+  /** Questions to display. */
+  questions: AskUserQuestionItem[]
+  /** Calling agent, when the request came from an agent tool call. */
+  agent?: Agent
+  /** Abort signal for the owning tool/step. */
+  signal?: AbortSignal
+}
+```
+
+## Answer
+
+Providers return one answer per answered question id. `selected` contains selected option labels, and `custom` carries a free-form "Other" answer when the user typed one. When `custom` is present, `selected` is empty; custom text is an answer override, not a supplement to selected choices.
+
+```ts type-equiv
+interface AskUserQuestionAnswerItem {
+  /** The answered question id. */
+  id: string
+  /** Selected option labels. Empty when the answer is purely custom text. */
+  selected: string[]
+  /** Optional free-text "Other" answer. */
+  custom?: string
+}
+```
+
+```ts type-equiv
+interface AskUserQuestionAnswer {
+  /** Structured answers keyed by question id. */
+  answers: AskUserQuestionAnswerItem[]
+}
+```
+
+## Provider
+
+Only one provider may be active in a context. Provider registration is effect-bound so HMR/disposal removes the active UI.
+
+```ts type-equiv
+interface UserInteractionProvider {
+  ask(request: AskUserQuestionRequest): Promise<AskUserQuestionAnswer>
+}
+```
+
+## Errors
+
+`UserInteractionError` extends `HarnessError`, so `ctx.tools.execute()` preserves `{ name, code }` for model-facing tool failures such as `EMPTY_QUESTIONS`, `NO_PROVIDER`, `ASK_ABORTED`, or ACP-side cancellation.
+
+```ts type-equiv
+class UserInteractionError extends HarnessError {
+  constructor(message: string, code: string, options?: ErrorOptions) {
+    super(message, code, options)
+    this.name = 'UserInteractionError'
+  }
+}
+```
--- a/docs/module-graph.md
+++ b/docs/module-graph.md
@@ -83,6 +83,8 @@ flowchart TD
    pkg_acp_agent["acp-agent"]
    pkg_app_boot["app-boot"]
    pkg_stdio_agent["stdio-agent"]
+    pkg_tool_ask_user["tool-ask-user"]
+    pkg_user_interaction["user-interaction"]
  end
  subgraph group_code_runtime["packages/code-runtime"]
    pkg_code_runtime["code-runtime"]
@@ -136,6 +138,8 @@ flowchart TD
  pkg_invariants --> pkg_agent
  pkg_invariants --> pkg_llm
  pkg_invariants --> pkg_session
+  pkg_user_interaction --> pkg_agent
+  pkg_user_interaction --> pkg_llm
  pkg_agent_loop --> pkg_agent
  pkg_agent_loop --> pkg_llm
  pkg_agent_loop --> pkg_session
@@ -175,6 +179,10 @@ flowchart TD
  pkg_acp --> pkg_session
  pkg_acp --> pkg_session_persistence
  pkg_acp --> pkg_tools
+  pkg_acp --> pkg_user_interaction
+  pkg_tool_ask_user --> pkg_agent
+  pkg_tool_ask_user --> pkg_tools
+  pkg_tool_ask_user --> pkg_user_interaction
  pkg_repeat_tool_guard --> pkg_agent
  pkg_repeat_tool_guard --> pkg_tools
  pkg_agent_core --> pkg_agent
@@ -218,12 +226,15 @@ flowchart TD
  pkg_acp_agent --> pkg_agent_core
  pkg_acp_agent --> pkg_app_boot
  pkg_acp_agent --> pkg_session_persistence_jsonl
+  pkg_acp_agent --> pkg_user_interaction
  pkg_stdio_agent --> pkg_agent
  pkg_stdio_agent --> pkg_agent_core
  pkg_stdio_agent --> pkg_app_boot
  pkg_stdio_agent --> pkg_llm
  pkg_stdio_agent --> pkg_session
  pkg_stdio_agent --> pkg_session_persistence_jsonl
+  pkg_stdio_agent --> pkg_tool_ask_user
+  pkg_stdio_agent --> pkg_user_interaction
 ```

 | Package | Group | Depends on |
@@ -260,6 +271,7 @@ flowchart TD
 | [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl) | `session-persistence` | [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence) |
 | [`session-persistence-sqlite`](../packages/session-persistence/session-persistence-sqlite) | `session-persistence` | [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence) |
 | [`invariants`](../packages/support/invariants) | `support` | [`agent`](../packages/core/agent), [`llm`](../packages/llm/llm), [`session`](../packages/core/session) |
+| [`user-interaction`](../packages/ui/user-interaction) | `ui` | [`agent`](../packages/core/agent), [`llm`](../packages/llm/llm) |
 | [`agent-loop`](../packages/core/agent-loop) | `core` | [`agent`](../packages/core/agent), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools) |
 | [`tool-bash`](../packages/bash/tool-bash) | `bash` | [`agent`](../packages/core/agent), [`bash`](../packages/bash/bash), [`llm`](../packages/llm/llm), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools) |
 | [`tool-fs`](../packages/fs/tool-fs) | `fs` | [`fs`](../packages/fs/fs), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`system-prompt`](../packages/core/system-prompt), [`tools`](../packages/core/tools) |
@@ -268,7 +280,8 @@ flowchart TD
 | [`timeout-policy`](../packages/timeout/timeout-policy) | `timeout` | [`llm`](../packages/llm/llm), [`timeout`](../packages/util/timeout), [`tools`](../packages/core/tools) |
 | [`tool-todo`](../packages/todo/tool-todo) | `todo` | [`agent`](../packages/core/agent), [`session`](../packages/core/session), [`tools`](../packages/core/tools) |
 | [`hooks-codex`](../packages/hooks/hooks-codex) | `hooks` | [`agent`](../packages/core/agent), [`hook-protocol`](../packages/hooks/hook-protocol), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`tools`](../packages/core/tools) |
-| [`acp`](../packages/ui/acp) | `ui` | [`agent`](../packages/core/agent), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`tools`](../packages/core/tools) |
+| [`acp`](../packages/ui/acp) | `ui` | [`agent`](../packages/core/agent), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-persistence`](../packages/session-persistence/session-persistence), [`tools`](../packages/core/tools), [`user-interaction`](../packages/ui/user-interaction) |
+| [`tool-ask-user`](../packages/ui/tool-ask-user) | `ui` | [`agent`](../packages/core/agent), [`tools`](../packages/core/tools), [`user-interaction`](../packages/ui/user-interaction) |
 | [`repeat-tool-guard`](../packages/guard/repeat-tool-guard) | `guard` | [`agent`](../packages/core/agent), [`tools`](../packages/core/tools) |
 | [`agent-core`](../packages/core/agent-core) | `core` | [`agent`](../packages/core/agent), [`agent-loop`](../packages/core/agent-loop), [`invariants`](../packages/support/invariants), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`system-prompt`](../packages/core/system-prompt), [`tool-bash`](../packages/bash/tool-bash), [`tools`](../packages/core/tools) |
 | [`subagent-acp`](../packages/subagent/subagent-acp) | `subagent` | [`agent`](../packages/core/agent), [`llm`](../packages/llm/llm), [`subagent`](../packages/subagent/subagent), [`subagent-subprocess`](../packages/subagent/subagent-subprocess) |
@@ -278,5 +291,5 @@ flowchart TD
 | [`subagent-mock`](../packages/support/subagent-mock) | `support` | [`agent`](../packages/core/agent), [`llm`](../packages/llm/llm), [`subagent`](../packages/subagent/subagent) |
 | [`subagent-fork`](../packages/subagent/subagent-fork) | `subagent` | [`agent`](../packages/core/agent), [`session`](../packages/core/session), [`subagent`](../packages/subagent/subagent), [`subagent-inprocess`](../packages/subagent/subagent-inprocess) |
 | [`subagent-spawn`](../packages/subagent/subagent-spawn) | `subagent` | [`subagent`](../packages/subagent/subagent), [`subagent-inprocess`](../packages/subagent/subagent-inprocess) |
-| [`acp-agent`](../packages/ui/acp-agent) | `ui` | [`acp`](../packages/ui/acp), [`agent-core`](../packages/core/agent-core), [`app-boot`](../packages/ui/app-boot), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl) |
-| [`stdio-agent`](../packages/ui/stdio-agent) | `ui` | [`agent`](../packages/core/agent), [`agent-core`](../packages/core/agent-core), [`app-boot`](../packages/ui/app-boot), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl) |
+| [`acp-agent`](../packages/ui/acp-agent) | `ui` | [`acp`](../packages/ui/acp), [`agent-core`](../packages/core/agent-core), [`app-boot`](../packages/ui/app-boot), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`user-interaction`](../packages/ui/user-interaction) |
+| [`stdio-agent`](../packages/ui/stdio-agent) | `ui` | [`agent`](../packages/core/agent), [`agent-core`](../packages/core/agent-core), [`app-boot`](../packages/ui/app-boot), [`llm`](../packages/llm/llm), [`session`](../packages/core/session), [`session-persistence-jsonl`](../packages/session-persistence/session-persistence-jsonl), [`tool-ask-user`](../packages/ui/tool-ask-user), [`user-interaction`](../packages/ui/user-interaction) |
--- a/docs/rfc/INDEX.md
+++ b/docs/rfc/INDEX.md
@@ -55,6 +55,7 @@ Generated by `pnpm run gen-rfc-index` from the RFC tree — never edit by hand;
 | [Compaction as a capability seam (abstract contract + basic backend)](implemented/feature/2026-06-18-compaction-capability-seam.md) | 2026-06-18 |
 | [Subagent capability seam](implemented/feature/2026-06-21-subagent-capability-seam.md) | 2026-06-21 |
 | [ACP subagent backend (out-of-process delegation)](implemented/feature/2026-06-22-acp-subagent-backend.md) | 2026-06-22 |
+| [Ask-user question capability](implemented/feature/2026-06-25-ask-user-question.md) | 2026-06-25 |
 | [The `todo_write` tool — model task list as event-sourced session state](implemented/feature/2026-06-29-todo-write-tool.md) | 2026-06-29 |
 | [dsh-hooks-claude + dsh-hooks-codex — the Claude Code / Codex hook bridges](implemented/feature/2026-06-30-hook-bridges.md) | 2026-06-30 |
 | [dsh-hook-protocol — the shared Claude Code / Codex hook wire-protocol core](implemented/feature/2026-06-30-hook-protocol-lib.md) | 2026-06-30 |
--- a/docs/rfc/implemented/feature/2026-06-25-ask-user-question.md
+++ b/docs/rfc/implemented/feature/2026-06-25-ask-user-question.md
@@ -0,0 +1,49 @@
+# RFC: Ask-user question capability
+
+Status: implemented
+
+## Problem
+
+The agent sometimes cannot proceed safely from model inference alone: it needs the human to choose a path, confirm a risky/default action, or provide missing information. Before this change, the only way to get that answer was for the model to ask in assistant text and then stop, which broke the normal tool-call loop: the agent had no structured way to pause, no option metadata for UIs, no abort/error taxonomy, and no way for non-stdio front doors to present the question consistently.
+
+This is a user-facing capability, but it also crosses package boundaries. A model-facing tool needs a provider-neutral request vocabulary; each UI surface needs to decide how to show and collect the answer; the agent loop should remain unchanged because a tool call already has the right async shape.
+
+## Decision
+
+Introduce `dsh-user-interaction` as the provider-neutral interface package for `ctx.userInteraction`, colocated with the model-facing consumer `dsh-tool-ask-user` under `packages/ui`. The grouping is intentional: asking a human is a UI-backed product affordance, not part of the providerless core spine. The seam still owns the stable request/answer/error vocabulary, while UI product surfaces provide the concrete provider that collects the answer. The tool registers `ask_user_question`, forwards `{ questions, agent, signal }`, and returns the provider-computed structured answers as the tool result.
+
+The model-facing request vocabulary is deliberately aligned with the product-research schema: `ask_user_question({ questions: [{ id, question, header?, options?: [{ label, description? }], multi_select? }] })`. `id` is supplied per question and echoed in the result so a batch can be routed without relying on question text. `label` is both user-facing display text and the selected value returned to the model; there is no separate `value`, no `recommended`, no `allow_custom`, and no `desc` alias.
+
+Providers return `{ answers: [{ id, selected, custom? }] }`. `selected` is always an array of selected option labels, so single-select and `multi_select` answers share one result shape. `custom` carries a free-text "Other" answer; optionless questions collect `custom` directly. When `custom` is present, it overrides any selected choices and `selected` is empty.
+
+`UserInteractionError` extends `HarnessError`, so failures such as `NO_PROVIDER`, `ASK_ABORTED`, ACP cancellation, or missing session routing survive `ctx.tools.execute()` as machine-routable `{ name, code }` tool errors. This matches the structured-error taxonomy and lets the model or a wrapping plugin distinguish "user cancelled" from a generic thrown exception.
+
+## UI mappings
+
+`dsh-stdio-agent`'s in-package readline module renders each question, shows each option's `description` on the next line, supports comma/space-separated numeric choices for `multi_select`, accepts free-form custom answers, and rejects pending questions on abort, provider disposal, or stdin EOF. A batched request is asked in order and resolved as one answer object. The stdio provider serializes simultaneous requests with an internal queue so only one prompt owns stdin at a time.
+
+`dsh-acp` provides the same seam for ACP sessions. It routes an ask request from the calling `Agent` through the bridge's `agent→sessionId` reverse map and calls ACP `unstable_createElicitation` with a session-scoped form for each question. Single-select options become a `choice` string enum; `multi_select` options become a `choice` array enum; optionless questions use a required `custom` text field. If the client returns both `choice` and non-empty `custom`, the custom answer wins. ACP `decline`/`cancel`, a missing answer, a missing session, and a client without elicitation support all become structured `UserInteractionError`s.
+
+The ACP mapping deliberately uses elicitation, not `session/request_permission`. `request_permission` is still reserved for the separate permission gate: it is a yes/no-or-policy authorization protocol around tool execution. `ask_user_question` is a general information-gathering tool with optional free-form answers, so ACP form elicitation is the closer protocol fit. The bridge's session routing is shared with the future permission gate, but the user intent is different.
+
+## Alternatives considered
+
+**Assistant text followed by a stopped turn.** The model could ask the user in plain assistant text and then stop. That loses the structured option metadata, gives UIs no provider-neutral way to render a choice, and forces the next human answer to arrive as a new user prompt rather than as the result of the operation that needed the answer.
+
+**Core-owned ask-user packages.** The first implementation split the seam and the model-facing tool across `packages/core` and `packages/ui`, but both names describe one UI-backed human-interaction affordance. The seam remains provider-neutral, but it is not providerless core infrastructure like sessions, tools, or the agent registry. Keeping `dsh-user-interaction` and `dsh-tool-ask-user` together under `packages/ui` makes the package map match the product boundary: apps and bridges provide the human-answer provider, and the stdio app opts into the model-facing tool.
+
+**ACP `session/request_permission`.** Permission requests are authorization around tool execution; `ask_user_question` is information gathering with optional free-form answers. Using permission for general questions would collapse two different product concepts and make the future permission gate harder to reason about.
+
+**A loop-level pause primitive.** The agent loop already knows how to await a tool call and resume from a tool result. Adding a new loop special case would duplicate that async shape and make every loop implementation learn about a UI concern.
+
+## Consequences
+
+ACP elicitation is currently marked unstable in the SDK. The fallback is still structured: if a client does not implement it, the tool returns `ASK_FAILED` rather than hanging. A later ACP stabilization may rename or reshape the method; that migration should stay inside `dsh-acp` because the core `ctx.userInteraction` vocabulary is provider-neutral.
+
+The feature gives the model a powerful pause primitive, so prompt guidance matters. The tool description tells the model to ask concise questions and use options when possible. Product policy can later wrap `tools/execute` to restrict when the tool is allowed, but the loop should not special-case it.
+
+`dsh-user-interaction` and `dsh-tool-ask-user` both live in `packages/ui` because they form one product-facing human-interaction capability. `agent-core` does not load either the tool or a provider. `stdio-agent` opts into the seam, its readline provider, and the model-facing tool. `acp-agent` keeps only the `userInteraction` seam/provider by default: ACP elicitation support is still client-dependent, so an ACP leaf must opt into the model-facing tool deliberately once its client can complete elicitation requests.
+
+## Testing
+
+Unit coverage pins provider registration/disposal, duplicate-provider rejection, abort-before-provider, empty-question rejection, structured tool errors through `ctx.tools.execute()`, batched answers, multi-select answers, custom answers, and the model schema including the removal of `value`, `recommended`, `allow_custom`, and `desc`. `dsh-stdio-agent` tests cover option descriptions, queued requests, EOF/abort cleanup, optionless free-form input, invalid option reprompts, duplicate multi-select numbers, and batched question flows. ACP bridge tests drive a real in-memory ACP connection with the real `ask_user_question` tool and verify selected-option, custom-overrides-choice, multi-select, and optionless free-form elicitation paths continue the agent loop.
--- a/docs/tool-catalog.md
+++ b/docs/tool-catalog.md
@@ -15,12 +15,83 @@ This table connects model-visible tool names to the plugin package and service s

 | Tool package | Model-visible names | Requires | Writes / affects | Shipped aliases | Deployment note |
 | --- | --- | --- | --- | --- | --- |
+| `@deepseek-ai/dsh-tool-ask-user` | `ask_user_question` | `ctx.tools`, `ctx.userInteraction` | `tool/call`, `tool/result after a UI/provider answers the question` | - | ask_user_question pauses the tool call until the active UI provider returns a human answer. |
 | `@deepseek-ai/dsh-tool-bash` | `bash`, `bash_kill`, `bash_output` | `ctx.tools`, `ctx.bash` | `tool/call`, `tool/result`, `context/message via agent.inject() for background completion notices` | - | The bash/bash_output/bash_kill tools are model-facing consumers of the bash executor seam. |
 | `@deepseek-ai/dsh-tool-fs` | `edit`, `read`, `write` | `ctx.tools`, `ctx.fs`, `ctx.systemPrompt` | `tool/call`, `fs/write-intent or fs/edit-intent for mutations`, `fs/observed after successful file operations`, `tool/result` | - | The read-before-write/edit policy is added by `@deepseek-ai/dsh-fs-policy` (an `fs/*` event-gate plugin, no schema change); a deployment that loads these tools is expected to also load it. The tool schemas above are identical with or without the policy plugin. |
 | `@deepseek-ai/dsh-tool-subagent` | `subagent` | `ctx.tools`, `ctx.subagents` | `tool/call`, `tool/result`, `child session events through the chosen provider` | `subagent`, `subagent_fork` | The registered tool name is the load-time `toolName` config (default `subagent`); the schema above is that default. The shipped example agents load this package once per subagent backend, so the model additionally sees `subagent_fork` (bound to the fork backend) with an identical schema — see `examples/coding-agent/cordis.yml` and `examples/acp-agent/cordis.yml`. |
 | `@deepseek-ai/dsh-tool-todo` | `todo_write` | `ctx.tools`, `owning Agent session` | `tool/call`, `todo/write`, `tool/result` | - | todo_write is session-owned state; UIs render the latest todo/write event as a checklist or ACP plan. |
 | `@deepseek-ai/dsh-tool-web` | `web_fetch`, `web_search` | `ctx.tools`, `ctx.web`, `ctx.systemPrompt` | `tool/call`, `tool/result` | - | web_search and web_fetch keep provider selection behind ctx.web so model-visible schemas stay stable across backend swaps. |

+## `@deepseek-ai/dsh-tool-ask-user`
+
+### `ask_user_question`
+
+Ask the user a concise question when you need confirmation, a choice, or missing information before proceeding. Send one or more questions, each with a stable id that will be echoed in the answer.
+
+```json
+{
+  "type": "object",
+  "properties": {
+    "questions": {
+      "type": "array",
+      "description": "Questions to ask the user before continuing.",
+      "items": {
+        "type": "object",
+        "properties": {
+          "id": {
+            "type": "string",
+            "description": "Stable id for this question; echoed in the answer."
+          },
+          "question": {
+            "type": "string",
+            "description": "The specific question to ask the user."
+          },
+          "header": {
+            "type": "string",
+            "description": "Optional short heading for the question, such as \"Confirm\" or \"Choose Mode\"."
+          },
+          "options": {
+            "type": "array",
+            "description": "Optional choices to show the user. If you recommend one, put it first and append \"(Recommended)\" to that label.",
+            "items": {
+              "type": "object",
+              "properties": {
+                "label": {
+                  "type": "string",
+                  "description": "Short user-facing option label."
+                },
+                "description": {
+                  "type": "string",
+                  "description": "One sentence explaining the tradeoff or impact."
+                }
+              },
+              "required": [
+                "label"
+              ]
+            }
+          },
+          "multi_select": {
+            "type": "boolean",
+            "description": "Whether the user may select more than one option. Defaults to false."
+          }
+        },
+        "required": [
+          "id",
+          "question"
+        ]
+      }
+    }
+  },
+  "required": [
+    "questions"
+  ]
+}
+```
+
+Source: [`packages/ui/tool-ask-user/src/index.ts`](../packages/ui/tool-ask-user/src/index.ts)
+
+ask_user_question pauses the tool call until the active UI provider returns a human answer.
+
 ## `@deepseek-ai/dsh-tool-bash`

 ### `bash`