list_forwarding_addresses

Retrieve and display the forwarding addresses configured for a specific Gmail account to manage email redirections effectively.

Instructions

Lists the forwarding addresses for the specified account

Input Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Implementation Reference

src/index.ts:1116-1125 (registration)

Registration of the 'list_forwarding_addresses' tool, including description, empty input schema, and inline handler that uses the Gmail API to list forwarding addresses for the account via handleTool and formatResponse.

server.tool("list_forwarding_addresses",
  "Lists the forwarding addresses for the specified account",
  {},
  async () => {
    return handleTool(config, async (gmail: gmail_v1.Gmail) => {
      const { data } = await gmail.users.settings.forwardingAddresses.list({ userId: 'me' })
      return formatResponse(data)
    })
  }
)

src/index.ts:1119-1124 (handler)
The handler function for 'list_forwarding_addresses' tool. It invokes handleTool which authenticates and calls the Gmail API's users.settings.forwardingAddresses.list method, then formats the response.
```
async () => {
  return handleTool(config, async (gmail: gmail_v1.Gmail) => {
    const { data } = await gmail.users.settings.forwardingAddresses.list({ userId: 'me' })
    return formatResponse(data)
  })
}
```

src/index.ts:50-80 (helper)

Shared helper function 'handleTool' used by all tools, including 'list_forwarding_addresses', to handle OAuth2 authentication, create Gmail client, execute the API call, and handle errors.

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 to format API responses into MCP content format for all tools.
```
const formatResponse = (response: any) => ({ content: [{ type: "text", text: JSON.stringify(response) }] })
```

Gmail MCP