[BUG] Gmail MCP fails — npm package @anthropic-ai/google-gmail-mcp returns 404

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Gmail MCP server fails to connect via /mcp in Claude Code CLI. The npm package @anthropic-ai/google-gmail-mcp does not exist on the public npm registry, so the server can never start.

What Should Happen?

Gmail MCP should connect successfully after authenticating via claude.ai integrations.

Error Messages/Logs

MCP server "gmail": Starting connection with timeout of 30000ms                                                   
  [ERROR] MCP server "gmail" Server stderr: npm error code E404                                                     
  npm error 404 Not Found - GET https://registry.npmjs.org/@anthropic-ai%2fgoogle-gmail-mcp - Not found             
  npm error 404 The requested resource '@anthropic-ai/google-gmail-mcp@*' could not be found           
  MCP server "gmail": Connection failed after 349ms: MCP error -32000: Connection closed

Steps to Reproduce

1. Connect Gmail integration via claude.ai → Settings → Integrations
2. Launch Claude Code CLI
3. Run /mcp
4. Gmail fails with "Failed to reconnect to gmail"

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.83 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

The root cause is that the npm package @anthropic-ai/google-gmail-mcp does not exist on the public npm registry.
The connection fails at the npm install step before any OAuth/Google authentication is attempted. Google account
permissions are correctly configured (verified in Google Security settings). Google Calendar MCP may have the same
issue — untested.