[BUG] Garbled/corrupted text rendering in terminal on macOS

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 running Claude Code in the VS Code integrated terminal on macOS, the terminal output displays garbled/corrupted text with random characters, wrong symbols, and broken encoding. The text is completely unreadable — all output appears as a jumble of incorrect characters instead of the expected readable text.

This seems to be a terminal rendering/encoding issue specific to macOS, as the same environment on other platforms works correctly.

What Should Happen?

The terminal output should display clean, readable text without any garbled or corrupted characters. Claude Code should render all text correctly in the VS Code integrated terminal on macOS.

Error Messages/Logs

Steps to Reproduce

1. Open VS Code on macOS
2. Open the integrated terminal (View > Terminal or Ctrl+`)
3. Run claude to start Claude Code
4. Observe that the terminal output is garbled/corrupted — text appears as random/broken characters instead of readable text

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.145

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

VS Code integrated terminal

Additional Information

<img width="1149" height="421" alt="Image" src="https://github.com/user-attachments/assets/a02b2569-5f51-46fd-b893-fada87ab001b" />

MacOS version: Version 26.3 (25D125)