list_messages
Retrieve and filter email messages from your Gmail mailbox using search queries, labels, and pagination controls.
Instructions
List messages in the user's mailbox with optional filtering
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| maxResults | No | Maximum number of messages to return. Accepts values between 1-500 | |
| pageToken | No | Page token to retrieve a specific page of results | |
| q | No | Only return messages matching the specified query. Supports the same query format as the Gmail search box | |
| labelIds | No | Only return messages with labels that match all of the specified label IDs | |
| includeSpamTrash | No | Include messages from SPAM and TRASH in the results | |
| includeBodyHtml | No | Whether to include the parsed HTML in the return for each body, excluded by default because they can be excessively large |
Implementation Reference
- src/index.ts:594-623 (registration)Registration of the 'list_messages' MCP tool, including input schema definition with Zod and the inline async handler function that executes the Gmail users.messages.list API call, processes message payloads (decoding bodies, filtering headers), and formats the response for MCP.server.tool("list_messages", "List messages in the user's mailbox with optional filtering", { maxResults: z.number().optional().describe("Maximum number of messages to return. Accepts values between 1-500"), pageToken: z.string().optional().describe("Page token to retrieve a specific page of results"), q: z.string().optional().describe("Only return messages matching the specified query. Supports the same query format as the Gmail search box"), labelIds: z.array(z.string()).optional().describe("Only return messages with labels that match all of the specified label IDs"), includeSpamTrash: z.boolean().optional().describe("Include messages from SPAM and TRASH in the results"), includeBodyHtml: z.boolean().optional().describe("Whether to include the parsed HTML in the return for each body, excluded by default because they can be excessively large"), }, async (params) => { return handleTool(config, async (gmail: gmail_v1.Gmail) => { const { data } = await gmail.users.messages.list({ userId: 'me', ...params }) if (data.messages) { data.messages = data.messages.map((message: Message) => { if (message.payload) { message.payload = processMessagePart( message.payload, params.includeBodyHtml ) } return message }) } return formatResponse(data) }) } )
- src/index.ts:596-603 (schema)Input schema for the list_messages tool using Zod, defining optional parameters for pagination, search query, labels, spam/trash inclusion, and HTML body inclusion.{ maxResults: z.number().optional().describe("Maximum number of messages to return. Accepts values between 1-500"), pageToken: z.string().optional().describe("Page token to retrieve a specific page of results"), q: z.string().optional().describe("Only return messages matching the specified query. Supports the same query format as the Gmail search box"), labelIds: z.array(z.string()).optional().describe("Only return messages with labels that match all of the specified label IDs"), includeSpamTrash: z.boolean().optional().describe("Include messages from SPAM and TRASH in the results"), includeBodyHtml: z.boolean().optional().describe("Whether to include the parsed HTML in the return for each body, excluded by default because they can be excessively large"), },
- src/index.ts:50-80 (helper)Shared helper function 'handleTool' used by the list_messages handler (and all other tools) to manage OAuth2 authentication, validate credentials, create Gmail client, execute the provided API callback, and handle errors including auth-specific ones.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}` }); } }
- src/index.ts:94-108 (helper)Helper function 'processMessagePart' called by list_messages to recursively decode base64-encoded text/plain (and optionally text/html) bodies in message payloads, filter headers to specific list (Date, From, To, etc.), and process nested parts.const processMessagePart = (messagePart: MessagePart, includeBodyHtml = false): MessagePart => { if ((messagePart.mimeType !== 'text/html' || includeBodyHtml) && messagePart.body) { messagePart.body = decodedBody(messagePart.body) } if (messagePart.parts) { messagePart.parts = messagePart.parts.map(part => processMessagePart(part, includeBodyHtml)) } if (messagePart.headers) { messagePart.headers = messagePart.headers.filter(header => RESPONSE_HEADERS_LIST.includes(header.name || '')) } return messagePart }