[BUG] ClaudeCode is rambling nonsense to the point where it's completely useless for getting anything done.

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?

ClaudeCode is rambling nonsense to the point where it's completely useless for getting anything done.

What Should Happen?

I used the exact same prompt, and Codex nailed the core issue immediately. Meanwhile, ClaudeCode just completely misses the point—rambling nonsense, zero logical flow. Honestly feels dumber than Opus or Sonnet 4.5.

Error Messages/Logs

Steps to Reproduce

...

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

v2.1.109

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

WSL (Windows Subsystem for Linux)

Additional Information

_No response_