[BUG] Google Cloud BigQuery / Google Compute Engine connectors — persistent redirect_uri_mismatch (Error 400), duplicate of open issues
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?
Confirming this is still broken as of August 29, 2026. Both connectors fail to authenticate with:
Code
Gmail, Calendar, and Drive authenticate fine on the same Google account — this is isolated to the BigQuery/Compute Engine OAuth path specifically, confirming it's not an account or permissions issue on my end.
This matches previously filed reports that are still unresolved:
#43959 — BigQuery MCP connector OAuth fails with redirect_uri_mismatch
#62271 — Google Cloud BigQuery MCP connector: OAuth redirect_uri_mismatch, also notes Google_Compute_Engine shares the same auth flow and is likely affected
#48957 — BigQuery MCP connector fails with redirect_uri_mismatch for Workspace accounts
Root cause per #43959: the OAuth client_id 699272716442-c8vv4tojssh38erhltaj70k0lmi7p449.apps.googleusercontent.com (Anthropic's own client) has a redirect URI registered with Google that doesn't match what's being sent — this needs to be fixed server-side in Anthropic's OAuth client config, not something end users can resolve.
What Should Happen?
Status update on when this gets fixed. It's been open since at least April 2026 with no resolution across three separate reports.
Error Messages/Logs
Steps to Reproduce
Try to connect either connector and error shows
Claude Model
Sonnet (default)
Is this a regression?
I don't know
Last Working Version
_No response_
Claude Code Version
Not using clode code, web access and mobile app
Platform
Anthropic API
Operating System
Windows
Terminal/Shell
Terminal.app (macOS)
Additional Information
_No response_