Gmail MCP Server

Instructions

Implementation Reference

• src/index.ts:818-829 (registration)

  Registration of the 'untrash_thread' tool, including input schema and inline handler. The handler uses the Gmail API to remove a thread from trash by ID.
  server.tool("untrash_thread", "Remove a thread from the trash", { id: z.string().describe("The ID of the thread to remove from trash") }, async (params) => { return handleTool(config, async (gmail: gmail_v1.Gmail) => { const { data } = await gmail.users.threads.untrash({ userId: 'me', id: params.id }) return formatResponse(data) }) } )
• src/index.ts:823-828 (handler)

  The handler function for untrash_thread tool, which authenticates via handleTool and calls Gmail's threads.untrash API.
  async (params) => { return handleTool(config, async (gmail: gmail_v1.Gmail) => { const { data } = await gmail.users.threads.untrash({ userId: 'me', id: params.id }) return formatResponse(data) }) }
• src/index.ts:820-822 (schema)

  Input schema for untrash_thread: requires a single 'id' parameter (string) - the thread ID.
  { id: z.string().describe("The ID of the thread to remove from trash") },
• src/index.ts:50-80 (helper)

  Shared helper function handleTool used by untrash_thread (and all tools) to manage OAuth2 authentication, Gmail client setup, API call execution, and error handling including auth-specific errors.
  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) { // Check for specific authentication errors if ( error.message?.includes("invalid_grant") || error.message?.includes("refresh_token") || error.message?.includes("invalid_client") || error.message?.includes("unauthorized_client") || error.code === 401 || error.code === 403 ) { return formatResponse({ error: `Authentication failed: ${error.message}. Please re-authenticate by running: npx @shinzolabs/gmail-mcp auth`, }); } return formatResponse({ error: `Tool execution failed: ${error.message}` }); } }