MCP Server for iOS Simulator

Implementation Reference

• src/mcp/mcp-server.ts:620-670 (registration)

  MCP tool registration for 'shutdown-simulator-by-udid', including input schema { udid: z.string() } and handler that calls simulatorManager.directShutdownByUDID and verifySimulatorShutdown

  this.server.tool(
    'shutdown-simulator-by-udid',
    {
      udid: z.string()
    },
    async (params) => {
      fileLogger.info(`Shutting down simulator directly by UDID: ${params.udid}`);
      try {
        const success = await simulatorManager.directShutdownByUDID(params.udid);
        
        if (!success) {
          return {
            content: [{
              type: 'text',
              text: `Failed to shutdown simulator with UDID: ${params.udid}`
            }],
            isError: true
          };
        }
        
        // Verify shutdown
        const verifySuccess = await simulatorManager.verifySimulatorShutdown(params.udid);
        
        if (!verifySuccess) {
          return {
            content: [{
              type: 'text',
              text: `Simulator shutdown command executed but simulator may still be running. UDID: ${params.udid}`
            }],
            isError: true
          };
        }
        
        return {
          content: [{
            type: 'text',
            text: `Simulator with UDID: ${params.udid} successfully shut down`
          }]
        };
      } catch (error) {
        fileLogger.error(`Failed to shutdown simulator by UDID: ${params.udid}`, { error });
        return {
          content: [{
            type: 'text',
            text: `Error: ${error instanceof Error ? error.message : String(error)}`
          }],
          isError: true
        };
      }
    }
  );

• src/simulator/simulator-manager.ts:410-421 (handler)

  Core handler function that executes the shutdown command via xcrun simctl shutdown ${udid}

  async directShutdownByUDID(udid: string): Promise<boolean> {
    fileLogger.info(`Attempting direct CLI shutdown for simulator: ${udid}`);
    try {
      const execAsync = promisify(exec);
      await execAsync(`xcrun simctl shutdown ${udid}`);
      fileLogger.info(`Direct CLI shutdown command completed for simulator: ${udid}`);
      return true;
    } catch (error) {
      fileLogger.error(`Failed direct CLI shutdown for simulator: ${udid}`, { error });
      return false;
    }
  }

• src/simulator/simulator-manager.ts:426-445 (helper)

  Helper function to verify the simulator has been shut down by checking booted simulators list

  async verifySimulatorShutdown(udid: string): Promise<boolean> {
    try {
      // Get all booted simulators
      const bootedSimulators = await this.getBootedSimulators();
      
      // Check if our UDID is still in the list of booted simulators
      const stillRunning = bootedSimulators.some(sim => sim.udid === udid);
      
      if (stillRunning) {
        fileLogger.warn(`Simulator ${udid} is still reported as running`);
        return false;
      } else {
        fileLogger.info(`Verified simulator ${udid} is shut down`);
        return true;
      }
    } catch (error) {
      fileLogger.error(`Failed to verify simulator shutdown status: ${udid}`, { error });
      return false;
    }
  }

• src/mcp/mcp-server.ts:622-624 (schema)

  Zod input schema for the tool: requires 'udid' string parameter.

  {
    udid: z.string()
  },