v1.9.7: ask_user_input elicitation tool

apps/server/src/services/tools.ts

@@ -405,6 +405,81 @@ export const skillResource: ToolDef<SkillResourceInputT> = {
   },
 };
 
+// Batch 9.7: ask_user_input. Interactive elicitation. The model emits a tool
+// call with 1-3 structured questions; the inference loop PAUSES (does not
+// execute the tool server-side, does not recurse) and waits for the frontend
+// to POST /api/chats/:id/answer_user_input with the user's selections. See
+// routes/messages.ts for the resume path and services/inference.ts for the
+// pause branch in executeToolPhase.
+const AskUserInputInput = z.object({
+  questions: z
+    .array(
+      z.object({
+        question: z.string().min(1).max(200),
+        type: z.enum(['single_select', 'multi_select']),
+        options: z.array(z.string().min(1).max(80)).min(2).max(6),
+      }),
+    )
+    .min(1)
+    .max(3),
+});
+type AskUserInputInputT = z.infer<typeof AskUserInputInput>;
+
+export const askUserInput: ToolDef<AskUserInputInputT> = {
+  name: 'ask_user_input',
+  description:
+    "Ask the user 1-3 structured questions through an inline picker UI. Use when you genuinely need a choice the user must make (e.g. scope, options, preferences) before continuing. Each question has 2-6 options and accepts free-text answers in addition. The tool call pauses the conversation until the user submits — the next assistant turn sees their answers as the tool result. Do not use for trivial yes/no clarifications you could infer; prefer it over multi-paragraph speculation about what the user might want.",
+  inputSchema: AskUserInputInput,
+  jsonSchema: {
+    type: 'function',
+    function: {
+      name: 'ask_user_input',
+      description:
+        'Ask the user 1-3 structured questions through an inline picker. Pauses the conversation until the user answers; the next turn sees their selections.',
+      parameters: {
+        type: 'object',
+        properties: {
+          questions: {
+            type: 'array',
+            minItems: 1,
+            maxItems: 3,
+            items: {
+              type: 'object',
+              properties: {
+                question: { type: 'string', description: '<=200 chars, shown to the user' },
+                type: {
+                  type: 'string',
+                  enum: ['single_select', 'multi_select'],
+                  description: 'single_select = at most one option; multi_select = any subset',
+                },
+                options: {
+                  type: 'array',
+                  minItems: 2,
+                  maxItems: 6,
+                  items: { type: 'string' },
+                  description: '2-6 strings, each <=80 chars; free-text input is always available alongside',
+                },
+              },
+              required: ['question', 'type', 'options'],
+              additionalProperties: false,
+            },
+          },
+        },
+        required: ['questions'],
+        additionalProperties: false,
+      },
+    },
+  },
+  // Server-side no-op. The "execution" of ask_user_input is the user's
+  // response, captured client-side and posted to /api/chats/:id/answer_user_input.
+  // The inference loop detects this tool by name and pauses before reaching
+  // executeToolCall — this fallback only runs if something bypasses that
+  // branch, in which case the pending sentinel matches the pause-path shape.
+  async execute(input) {
+    return { _pending: true, questions: input.questions };
+  },
+};
+
 export const ALL_TOOLS: ReadonlyArray<ToolDef<unknown>> = [
   viewFile as ToolDef<unknown>,
   listDir as ToolDef<unknown>,
@@ -414,6 +489,7 @@ export const ALL_TOOLS: ReadonlyArray<ToolDef<unknown>> = [
   skillFind as ToolDef<unknown>,
   skillUse as ToolDef<unknown>,
   skillResource as ToolDef<unknown>,
+  askUserInput as ToolDef<unknown>,
 ];
 
 // v1.8.2: forward-compatible read-only whitelist. An agent whose `tools` is
@@ -422,6 +498,8 @@ export const ALL_TOOLS: ReadonlyArray<ToolDef<unknown>> = [
 // default (10). Every tool in v1.8.2 happens to be read-only, so the
 // non-RO branch only takes effect once BooCoder lands write tools.
 // Batch 9.6: skill_* added; all still read-only.
+// Batch 9.7: ask_user_input added — it pauses execution but doesn't mutate
+// project state, so it belongs in the read-only set for budget purposes.
 export const READ_ONLY_TOOL_NAMES = [
   'view_file',
   'list_dir',
@@ -431,6 +509,7 @@ export const READ_ONLY_TOOL_NAMES = [
   'skill_find',
   'skill_use',
   'skill_resource',
+  'ask_user_input',
 ] as const;
 
 export const TOOLS_BY_NAME: Record<string, ToolDef<unknown>> = Object.fromEntries(