Gmail MCP Server

Instructions

Implementation Reference

• src/index.ts:548-558 (registration)

  Registration of the 'delete_message' MCP tool, including schema definition and inline handler function that deletes a Gmail message by ID using the Gmail API.
  server.tool("delete_message", "Immediately and permanently delete a message", { id: z.string().describe("The ID of the message to delete") }, async (params) => { return handleTool(config, async (gmail: gmail_v1.Gmail) => { const { data } = await gmail.users.messages.delete({ userId: 'me', id: params.id }) return formatResponse(data) }) }
• src/index.ts:553-558 (handler)

  Handler function for the delete_message tool. It invokes handleTool with the Gmail client to call users.messages.delete API endpoint.
  async (params) => { return handleTool(config, async (gmail: gmail_v1.Gmail) => { const { data } = await gmail.users.messages.delete({ userId: 'me', id: params.id }) return formatResponse(data) }) }
• src/index.ts:550-552 (schema)

  Input schema for delete_message tool: requires 'id' parameter as a string representing the Gmail message ID.
  { id: z.string().describe("The ID of the message to delete") },
• src/index.ts:50-66 (helper)

  Shared helper function handleTool used by delete_message (and other tools) to manage OAuth2 authentication, create Gmail client, and execute the API call.
  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}` } }