update_imap

Instructions

Implementation Reference

• src/index.ts:901-914 (registration)

  Registration of the 'update_imap' MCP tool, including input schema and inline handler function that updates Gmail IMAP settings via the Gmail API.

  server.tool("update_imap",
    "Updates IMAP settings",
    {
      enabled: z.boolean().describe("Whether IMAP is enabled for the account"),
      expungeBehavior: z.enum(['archive', 'trash', 'deleteForever']).optional().describe("The action that will be executed on a message when it is marked as deleted and expunged from the last visible IMAP folder"),
      maxFolderSize: z.number().optional().describe("An optional limit on the number of messages that can be accessed through IMAP")
    },
    async (params) => {
      return handleTool(config, async (gmail: gmail_v1.Gmail) => {
        const { data } = await gmail.users.settings.updateImap({ userId: 'me', requestBody: params })
        return formatResponse(data)
      })
    }
  )

• src/index.ts:908-913 (handler)

  Handler function for 'update_imap' tool: authenticates via handleTool, calls Gmail API to update IMAP settings, formats response.

  async (params) => {
    return handleTool(config, async (gmail: gmail_v1.Gmail) => {
      const { data } = await gmail.users.settings.updateImap({ userId: 'me', requestBody: params })
      return formatResponse(data)
    })
  }

• src/index.ts:903-907 (schema)

  Input schema for 'update_imap' tool using Zod: enabled (boolean), expungeBehavior (enum), maxFolderSize (number optional).

  {
    enabled: z.boolean().describe("Whether IMAP is enabled for the account"),
    expungeBehavior: z.enum(['archive', 'trash', 'deleteForever']).optional().describe("The action that will be executed on a message when it is marked as deleted and expunged from the last visible IMAP folder"),
    maxFolderSize: z.number().optional().describe("An optional limit on the number of messages that can be accessed through IMAP")
  },

• src/index.ts:50-80 (helper)

  Shared helper function handleTool used by all tools including update_imap: handles OAuth2 authentication, Gmail client creation, API call execution, and error handling.

  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:48-48 (helper)

  Shared helper formatResponse used in update_imap handler: formats API response as MCP content.

  const formatResponse = (response: any) => ({ content: [{ type: "text", text: JSON.stringify(response) }] })