[BUG] Formatting Issue in the claude

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?

Whenever the claude generate a response it always has a formatting error in the mardown. I always tell him explicitly to use the artificat because the text in md format is painful to read. Attaching screenshot. Treat as sev1 or sev2.

<img width="925" height="530" alt="Image" src="https://github.com/user-attachments/assets/dc33e48e-31ba-429c-a4f7-7f3c181f289b" />

What Should Happen?

It should correctly format the output.

Error Messages/Logs

Steps to Reproduce

It happens to me every single day on every response.

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

claude-sonnet-4-5-20250929

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_