[BUG] API Error 500 - Internal server error

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?

When I try to use Claude Code with MCP, after some requests, I get API Error 500.

What Should Happen?

Claude should continue my request without any issue, but it stops and shows the error.

Error Messages/Logs

API Error: 500 {"type":"error","error":{"type":"api_error","message":"Internal server error"},"request_id":"req_011CYV7q2YjkcRFMMru9dBjg"}

Steps to Reproduce

1. Run Claude Code from VS Code.
2. Use Claude Code with an MCP server.
3. After some requests, get the error.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.56

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_