Run Claude sessions on tasks with event streaming and restart recovery

api/openapi.yaml

@@ -125,6 +125,87 @@ paths:
         "404": { $ref: "#/components/responses/Error" }
         "409": { $ref: "#/components/responses/Error" }
 
+  /api/tasks/{taskId}/sessions:
+    parameters:
+      - { name: taskId, in: path, required: true, schema: { type: string } }
+    get:
+      operationId: listSessions
+      responses:
+        "200":
+          description: The task's agent sessions, oldest first.
+          content:
+            application/json:
+              schema:
+                type: array
+                items: { $ref: "#/components/schemas/AgentSession" }
+        "404": { $ref: "#/components/responses/Error" }
+    post:
+      operationId: createSession
+      description: Starts an agent session in the task's worktree and sends it the prompt as its first turn.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema: { $ref: "#/components/schemas/SessionCreate" }
+      responses:
+        "201":
+          description: The new session.
+          content:
+            application/json:
+              schema: { $ref: "#/components/schemas/AgentSession" }
+        "400": { $ref: "#/components/responses/Error" }
+        "404": { $ref: "#/components/responses/Error" }
+        "409": { $ref: "#/components/responses/Error" }
+
+  /api/sessions/{sessionId}:
+    parameters:
+      - { name: sessionId, in: path, required: true, schema: { type: string } }
+    get:
+      operationId: getSession
+      responses:
+        "200":
+          description: The session.
+          content:
+            application/json:
+              schema: { $ref: "#/components/schemas/AgentSession" }
+        "404": { $ref: "#/components/responses/Error" }
+
+  /api/sessions/{sessionId}/messages:
+    parameters:
+      - { name: sessionId, in: path, required: true, schema: { type: string } }
+    post:
+      operationId: sendMessage
+      description: Starts a new turn with this message. The session must be idle.
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema: { $ref: "#/components/schemas/MessageCreate" }
+      responses:
+        "202":
+          description: The turn has started.
+          content:
+            application/json:
+              schema: { $ref: "#/components/schemas/AgentSession" }
+        "400": { $ref: "#/components/responses/Error" }
+        "404": { $ref: "#/components/responses/Error" }
+        "409": { $ref: "#/components/responses/Error" }
+
+  /api/sessions/{sessionId}/interrupt:
+    parameters:
+      - { name: sessionId, in: path, required: true, schema: { type: string } }
+    post:
+      operationId: interruptSession
+      description: Ends the current turn.
+      responses:
+        "202":
+          description: The interrupt was delivered.
+          content:
+            application/json:
+              schema: { $ref: "#/components/schemas/AgentSession" }
+        "404": { $ref: "#/components/responses/Error" }
+        "409": { $ref: "#/components/responses/Error" }
+
   /api/events:
     get:
       operationId: streamEvents
@@ -222,6 +303,33 @@ components:
       properties:
         title: { type: string }
 
+    AgentSession:
+      type: object
+      required: [id, task_id, vendor, model, vendor_session_id, state, role, created_by, created_at]
+      properties:
+        id: { type: string }
+        task_id: { type: string }
+        vendor: { type: string, enum: [claude] }
+        model: { type: string, description: Requested model; empty means the vendor's default. }
+        vendor_session_id: { type: string }
+        state: { type: string, enum: [idle, running, completed] }
+        role: { type: string, enum: [implementer] }
+        created_by: { type: string }
+        created_at: { type: string, format: date-time }
+
+    SessionCreate:
+      type: object
+      required: [prompt]
+      properties:
+        prompt: { type: string }
+        model: { type: string }
+
+    MessageCreate:
+      type: object
+      required: [text]
+      properties:
+        text: { type: string }
+
     Event:
       type: object
       required: [seq, kind, actor, payload, created_at]
@@ -230,14 +338,16 @@ components:
         kind: { type: string }
         project_id: { type: string }
         task_id: { type: string }
+        agent_session_id: { type: string }
         actor: { type: string }
         payload: { type: object }
         created_at: { type: string, format: date-time }
 
     Status:
       type: object
-      required: [started_at, db_bytes, last_event_seq, projects, active_tasks, sse_clients]
+      required: [started_at, db_bytes, last_event_seq, projects, active_tasks, sse_clients, live_agents]
       properties:
+        live_agents: { type: integer, description: Agent processes currently running. }
         started_at: { type: string, format: date-time }
         db_bytes: { type: integer, format: int64 }
         last_event_seq: { type: integer, format: int64 }