Gmail MCP Server

import {z} from 'zod'; import type {McpServer} from '@modelcontextprotocol/sdk/server/mcp.js'; import type {Config} from './types.js'; import {makeGmailApiCall} from '../utils/gmail-api.js'; import {jsonResult} from '../utils/response.js'; const inputSchema = { id: z.string().describe('The ID of the message to retrieve'), format: z.enum(['minimal', 'full', 'raw', 'metadata']).default('full').describe('The format to return the message in'), metadataHeaders: z.array(z.string()).optional().describe('When format is metadata, only include these headers'), }; // Gmail message structure (simplified) const messagePartSchema: z.ZodType<unknown> = z.lazy(() => z.object({ partId: z.string().optional(), mimeType: z.string().optional(), filename: z.string().optional(), headers: z.array(z.object({ name: z.string(), value: z.string(), })).optional(), body: z.object({ attachmentId: z.string().optional(), size: z.number().optional(), data: z.string().optional(), }).optional(), parts: z.array(messagePartSchema).optional(), })); const outputSchema = z.object({ id: z.string(), threadId: z.string(), labelIds: z.array(z.string()).optional(), snippet: z.string().optional(), historyId: z.string().optional(), internalDate: z.string().optional(), payload: messagePartSchema.optional(), sizeEstimate: z.number().optional(), raw: z.string().optional(), }); export function registerMessageGet(server: McpServer, config: Config): void { server.registerTool( 'message_get', { title: 'Get message', description: 'Get a single message by ID. Consider using gmail_thread_get to get all messages in a conversation.', inputSchema, outputSchema, annotations: { readOnlyHint: true, }, }, async ({id, format, metadataHeaders}) => { const params = new URLSearchParams(); params.set('format', format); if (metadataHeaders?.length) { for (const header of metadataHeaders) { params.append('metadataHeaders', header); } } const result = await makeGmailApiCall('GET', `/users/me/messages/${id}?${params.toString()}`, config.token); return jsonResult(outputSchema.parse(result)); }, ); }