Gmail MCP Server

Instructions

Implementation Reference

• src/index.ts:861-870 (registration)

  Registration of the 'get_vacation' MCP tool, including description, empty input schema (no parameters), and inline handler function that fetches the user's vacation responder settings using the Gmail API.
  server.tool("get_vacation", "Get vacation responder settings", {}, async () => { return handleTool(config, async (gmail: gmail_v1.Gmail) => { const { data } = await gmail.users.settings.getVacation({ userId: 'me' }) return formatResponse(data) }) } )
• src/index.ts:864-869 (handler)

  Inline handler function for the get_vacation tool. It invokes the shared handleTool utility (which handles auth) to call Gmail's users.settings.getVacation API and formats the response.
  async () => { return handleTool(config, async (gmail: gmail_v1.Gmail) => { const { data } = await gmail.users.settings.getVacation({ userId: 'me' }) return formatResponse(data) }) }
• src/index.ts:50-66 (helper)

  Shared helper function used by all Gmail tools, including get_vacation. Handles OAuth2 client creation/validation, Gmail client setup, executes the API call, and error handling.
  const handleTool = async (queryConfig: Record<string, any> | undefined, apiCall: (gmail: gmail_v1.Gmail) => Promise<any>) => { try { const oauth2Client = queryConfig ? createOAuth2Client(queryConfig) : defaultOAuth2Client if (!oauth2Client) throw new Error('OAuth2 client could not be created, please check your credentials') const credentialsAreValid = await validateCredentials(oauth2Client) if (!credentialsAreValid) throw new Error('OAuth2 credentials are invalid, please re-authenticate') const gmailClient = queryConfig ? google.gmail({ version: 'v1', auth: oauth2Client }) : defaultGmailClient if (!gmailClient) throw new Error('Gmail client could not be created, please check your credentials') const result = await apiCall(gmailClient) return result } catch (error: any) { return `Tool execution failed: ${error.message}` } }
• src/index.ts:48-48 (helper)

  Helper function to format the Gmail API response into MCP-compatible content structure (JSON stringified text). Used in get_vacation handler.
  const formatResponse = (response: any) => ({ content: [{ type: "text", text: JSON.stringify(response) }] })
• src/index.ts:863-863 (schema)

  Input schema for get_vacation tool: empty object, indicating no input parameters required.
  {},