NodeMCU MCP Service

Implementation Reference

• mcp_server_sdk.js:25-50 (handler)

  Primary handler for 'list-devices' tool using official MCP SDK. Registers the tool, defines empty schema, and implements logic to list devices via DeviceManager.getAllDevices()

  server.tool(
    "list-devices",
    {}, // No parameters required
    async () => {
      try {
        const devices = deviceManager.getAllDevices();
        return {
          content: [{ 
            type: "text", 
            text: JSON.stringify({
              devices: devices.map(device => ({
                id: device.id,
                name: device.name,
                status: device.status,
                lastSeen: device.lastSeen
              })),
              count: devices.length
            }, null, 2)
          }]
        };
      } catch (error) {
        console.error('Error listing devices:', error);
        throw new Error(`Failed to list devices: ${error.message}`);
      }
    }
  );

• mcp_server.js:119-130 (handler)

  Handler function listDevices() implementing the core tool logic in the custom MCP server implementation

  async listDevices() {
    const devices = deviceManager.getAllDevices();
    return {
      devices: devices.map(device => ({
        id: device.id,
        name: device.name,
        status: device.status,
        lastSeen: device.lastSeen
      })),
      count: devices.length
    };
  }

• mcp_server.js:14-17 (schema)

  Schema definition for 'list-devices' tool in custom MCP server (no parameters, description provided)

  "list-devices": {
    description: "List all registered NodeMCU devices and their status",
    parameters: {}
  },

• services/DeviceManager.js:76-78 (helper)

  Supporting helper method getAllDevices() that returns all devices from the internal devices Map, called by both tool handlers

  getAllDevices() {
    return Array.from(this.devices.values());
  }

• mcp_server_sdk.js:25-27 (registration)

  Tool registration call in MCP SDK with name and schema

  server.tool(
    "list-devices",
    {}, // No parameters required