Google Tag Manager MCP Server

Instructions

Implementation Reference

• src/index.js:58-64 (registration)

  Registers the 'check_auth_status' tool, including its name, description, and empty input schema, in the ListToolsRequestSchema handler.

  {
    name: 'check_auth_status',
    description: '現在の認証状態を確認します',
    inputSchema: {
      type: 'object',
      properties: {},
    },

• src/index.js:58-64 (schema)

  Defines the input schema (empty object) for the check_auth_status tool.

  {
    name: 'check_auth_status',
    description: '現在の認証状態を確認します',
    inputSchema: {
      type: 'object',
      properties: {},
    },

• src/index.js:895-908 (handler)

  Main handler for executing the check_auth_status tool: retrieves OAuth2Auth from GTMClient, calls isAuthenticated(), and returns JSON response with status.

  case 'check_auth_status': {
    const oauth2Auth = this.gtmClient.getOAuth2Auth();
    const isAuthenticated = oauth2Auth.isAuthenticated();
    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify({
            authenticated: isAuthenticated,
            message: isAuthenticated ? '認証済みです' : '未認証です。get_auth_urlツールで認証URLを取得してください。'
          }, null, 2),
        },
      ],
    };

• src/oauth2-auth.js:183-185 (helper)

  Implements the authentication status check by verifying the presence of access_token in OAuth2 client credentials.

  isAuthenticated() {
    return !!this.oAuth2Client.credentials.access_token;
  }

• src/gtm-client.js:365-367 (helper)

  Helper method in GTMClient that provides the OAuth2Auth instance to the tool handler.

  getOAuth2Auth() {
    return this.oauth2Auth;
  }