Jules MCP Server

Instructions

Implementation Reference

• src/mcp/tools.ts:202-236 (handler)

  The `manageSession` method in the `JulesTools` class that implements the core execution logic for the `manage_session` tool. It handles `approve_plan` by calling `client.approvePlan` and `send_message` by calling `client.sendMessage`, with consistent error handling.

   * Tool: manage_session
   * Manages session lifecycle (approve plan, send feedback).
   * @param args - The arguments for managing a session.
   * @returns A JSON string representing the result of the action.
   */
  async manageSession(
    args: z.infer<typeof ManageSessionSchema>
  ): Promise<string> {
    return this.executeWithErrorHandling(async () => {
      if (args.action === 'approve_plan') {
        const session = await this.client.approvePlan(args.session_id);
        return {
          message: 'Plan approved. Session is now executing.',
          newState: session.state,
        };
      }
  
      if (args.action === 'send_message') {
        if (!args.message) {
          throw new Error('Message is required for send_message action');
        }
  
        const session = await this.client.sendMessage(args.session_id, {
          prompt: args.message,
        });
  
        return {
          message: 'Feedback sent to session',
          newState: session.state,
        };
      }
  
      throw new Error('Invalid action');
    });
  }

• src/mcp/tools.ts:55-69 (schema)

  Zod input validation schema for the `manage_session` tool, defining `session_id`, `action` (enum: approve_plan, send_message), and optional `message`.

  export const ManageSessionSchema = z.object({
    session_id: z
      .string()
      .regex(/^[\w-]+$/, 'Session ID contains invalid characters')
      .describe('The ID of the session to manage'),
    action: z
      .enum(['approve_plan', 'send_message'])
      .describe('Action to perform on the session'),
    message: z
      .string()
      .min(1, 'Message cannot be empty')
      .max(5000, 'Message must not exceed 5,000 characters')
      .optional()
      .describe('Message content (required for send_message action)'),
  });

• src/index.ts:322-325 (registration)

  Dispatch handler in `CallToolRequestSchema` that validates input with `ManageSessionSchema` and delegates to `this.tools.manageSession`.

  case 'manage_session': {
    const validated = ManageSessionSchema.parse(args);
    result = await this.tools.manageSession(validated);
    break;

• src/index.ts:226-245 (registration)

  Tool registration in `ListToolsRequestSchema` response, providing name, description, and input schema mirroring the Zod schema.

    name: 'manage_session',
    description:
      'Manage an active Jules session: approve plans or send feedback',
    inputSchema: {
      type: 'object',
      properties: {
        session_id: { type: 'string', description: 'Session ID' },
        action: {
          type: 'string',
          enum: ['approve_plan', 'send_message'],
          description: 'Action to perform',
        },
        message: {
          type: 'string',
          description: 'Message (required for send_message)',
        },
      },
      required: ['session_id', 'action'],
    },
  },