[BUG] Agent window fails to connect in VS Code when using AWS Bedrock (CLAUDE_CODE_USE_BEDROCK=true)

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?

The Agent window in VS Code does not connect when using AWS Bedrock as the provider.
The regular VS Code editor extension works fine with the same configuration.

## Environment

• Claude Code version: 2.1.142
• OS: Windows 11 Enterprise
• VS Code with Claude Code extension
• Provider: AWS Bedrock (CLAUDE_CODE_USE_BEDROCK=true)

What Should Happen?

Agent window should connect (or show a clear error explaining Bedrock is unsupported)

Error Messages/Logs

I only see 403 in VS Code Agent Window

Steps to Reproduce

1. Set CLAUDE_CODE_USE_BEDROCK=true in ~/.claude/settings.json
2. Open VS Code with Claude Code extension
3. Open the Agent window
4. Observe: Agent window fails to connect

Claude Model

Sonnet (default)

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

2.1.142

Platform

AWS Bedrock

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_