feat(agent): ask_user tool via MCP elicitation, multi-channel routing

src/daemon/agent-runtime.ts

@@ -91,8 +91,22 @@ export class AgentRuntime {
   private slackWorkspaces?: Array<{ teamId: string; teamName: string; userId: string }>;
   private notificationDefault?: { platform: string; channelId: string; label?: string };
 
+  // Optional elicitation manager (set by gateway). When present, the SDK's
+  // `onElicitation` callback routes ask_user requests through it.
+  private elicitationManager?: import("./elicitation-manager.ts").ElicitationManager;
+
   private initialized = false;
 
+  /** Wire in the elicitation manager. Called by the gateway after construction. */
+  setElicitationManager(mgr: import("./elicitation-manager.ts").ElicitationManager): void {
+    this.elicitationManager = mgr;
+  }
+
+  /** Expose the elicitation manager so channel adapters can resolve answers. */
+  getElicitationManager(): import("./elicitation-manager.ts").ElicitationManager | undefined {
+    return this.elicitationManager;
+  }
+
   /** Get the configured model name. */
   getModel(): string {
     return this.config?.model ?? "claude-sonnet-4-6";
@@ -685,6 +699,11 @@ export class AgentRuntime {
         sessionKey,
         userState,
         personaPrompt,
+        {
+          platform: message.platform,
+          channelId: message.channelId,
+          threadId: message.threadId,
+        },
       );
 
       // Cache the new SDK session ID
@@ -746,6 +765,11 @@ export class AgentRuntime {
             sessionKey,
             userState,
             personaPrompt,
+            {
+              platform: message.platform,
+              channelId: message.channelId,
+              threadId: message.threadId,
+            },
           );
 
           if (result.sessionId) {
@@ -785,6 +809,11 @@ export class AgentRuntime {
                 sessionKey,
                 userState,
                 personaPrompt,
+                {
+                  platform: message.platform,
+                  channelId: message.channelId,
+                  threadId: message.threadId,
+                },
               );
               if (upgraded.sessionId) {
                 this.sdkSessionIds.set(sessionKey, upgraded.sessionId);
@@ -824,6 +853,12 @@ export class AgentRuntime {
     sessionKey?: string,
     userState?: string,
     personaPrompt?: string,
+    /**
+     * Source channel of the incoming message — used so the elicitation
+     * manager renders `ask_user` questions back on the user's active
+     * channel. Optional so non-message runs (cron, internal) keep working.
+     */
+    source?: { platform: string; channelId: string; threadId?: string },
   ): Promise<{
     text: string;
     sessionId?: string;
@@ -855,6 +890,16 @@ export class AgentRuntime {
       systemPromptAppend = systemPromptAppend + "\n\n" + personaPrompt;
     }
 
+    // Build the elicitation callback for this turn. The `ask_user` MCP
+    // tool calls `extra.sendRequest({method: "elicitation/create"})`;
+    // the SDK forwards to `onElicitation`, we route to the channel the
+    // user is currently talking to us on, and return their answer.
+    const mgr = this.elicitationManager;
+    const onElicitation: import("../sdk/session.ts").RunSessionParams["onElicitation"] =
+      mgr && source
+        ? (request, opts) => mgr.handleElicitation(request, source, opts.signal)
+        : undefined;
+
     const sdkQuery = runSession({
       prompt,
       model: model ?? this.config.model,
@@ -869,6 +914,7 @@ export class AgentRuntime {
       anthropicBaseUrl: this.config.anthropicBaseUrl,
       plugins: this.plugins,
       useSubscription: this.config.useSubscription,
+      onElicitation,
       stderr: (data: string) => {
         // Log SDK subprocess stderr so we can diagnose crash reasons
         const trimmed = data.trim();

src/daemon/channels/slack-user.ts

@@ -50,6 +50,14 @@ export class SlackUserAdapter implements ChannelAdapter {
   private teamName: string | null = null;
   private onMessage: (msg: IncomingMessage) => void;
   private draftManager: DraftManager;
+  // Optional elicitation manager — wired in by gateway after construction.
+  // Used by the ask_user button action handler to resolve pending requests.
+  private elicitationManager?: import("../elicitation-manager.ts").ElicitationManager;
+
+  /** Inject the elicitation manager. Called by gateway after adapter creation. */
+  setElicitationManager(mgr: import("../elicitation-manager.ts").ElicitationManager): void {
+    this.elicitationManager = mgr;
+  }
 
   // Default channel -- the user's direct chat channel with the agent
   private defaultChannelId: string | null = null;
@@ -263,6 +271,25 @@ export class SlackUserAdapter implements ChannelAdapter {
       });
     });
 
+    // ask_user button clicks. action_id is `ask_user_option:<index>`;
+    // value is `<elicitation-id>::<option-index>`. The elicitation
+    // manager resolves the pending request and we replace the original
+    // question with a "you chose X" acknowledgement.
+    this.app.action(/^ask_user_option:\d+$/, async ({ action, ack, respond }) => {
+      await ack();
+      const value = (action as { value?: string }).value;
+      if (!value) return;
+      const mgr = this.elicitationManager;
+      if (!mgr) return;
+      const { resolved, label } = mgr.resolveByButton(value);
+      if (resolved && label) {
+        await respond({
+          replace_original: true,
+          text: `:white_check_mark: You chose: *${label}*`,
+        });
+      }
+    });
+
     // Edit draft: open a modal with the draft content for editing
     this.app.action("edit_draft", async ({ action, ack, body }) => {
       await ack();
@@ -429,6 +456,32 @@ export class SlackUserAdapter implements ChannelAdapter {
     return result.ts;
   }
 
+  /**
+   * Post a message with Block Kit blocks. Used by the elicitation manager
+   * to render `ask_user` questions with interactive buttons. Falls back to
+   * plain text on platforms that ignore blocks. Same default-channel
+   * guard as postMessage — we only render interactive UIs in the channel
+   * the user actually watches.
+   */
+  async postBlocks(
+    channelId: string,
+    fallbackText: string,
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    blocks: any[],
+    threadId?: string,
+  ): Promise<string | undefined> {
+    if (channelId !== this.defaultChannelId) return undefined;
+    const client = this.clientFor(channelId);
+    if (!client) return undefined;
+    const result = await client.chat.postMessage({
+      channel: channelId,
+      text: fallbackText,
+      blocks,
+      thread_ts: threadId,
+    });
+    return result.ts;
+  }
+
   /**
    * Update an existing message (for streaming support).
    * Only works in the default channel (matches postMessage guard).