update_language
Change the display language for your Gmail interface by specifying a valid language tag to customize your email management experience.
Instructions
Updates language settings
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| displayLanguage | Yes | The language to display Gmail in, formatted as an RFC 3066 Language Tag |
Implementation Reference
- src/index.ts:921-926 (handler)Handler function for the 'update_language' tool. It invokes the Gmail API's users.settings.updateLanguage method via the shared handleTool wrapper to update the display language.
async (params) => { return handleTool(config, async (gmail: gmail_v1.Gmail) => { const { data } = await gmail.users.settings.updateLanguage({ userId: 'me', requestBody: params }) return formatResponse(data) }) } - src/index.ts:918-920 (schema)Input schema using Zod for validating the 'displayLanguage' parameter of the update_language tool.
{ displayLanguage: z.string().describe("The language to display Gmail in, formatted as an RFC 3066 Language Tag") }, - src/index.ts:916-927 (registration)Registration of the 'update_language' tool on the MCP server, including name, description, schema, and handler.
server.tool("update_language", "Updates language settings", { displayLanguage: z.string().describe("The language to display Gmail in, formatted as an RFC 3066 Language Tag") }, async (params) => { return handleTool(config, async (gmail: gmail_v1.Gmail) => { const { data } = await gmail.users.settings.updateLanguage({ userId: 'me', requestBody: params }) return formatResponse(data) }) } ) - src/index.ts:50-80 (helper)Shared helper function used by all Gmail tools, including update_language, to handle OAuth2 authentication, client creation, error handling, and API call execution.
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}` }); } }