[BUG] Bedrock Sonnet API error when connecting to Claude Code: Unexpected value for `anthropic-beta` header

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?

API Error: 400 {"error":{"message":"{\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\n \"message\":\"Unexpected value(s) tool-examples-2025-10-29 for the anthropic-beta header. Please \n consult our documentation at docs.anthropic.com or try again without the \n header.\"},\"request_id\":\"req_vrtx_011CV9FbW8EZVPrWadzgrzSS\"}. Received Model \n Group=xxxx-bedrock-claude-4-sonnet\nAvailable Model Group \n Fallbacks=None","type":"None","param":"None","code":"400"}}

What Should Happen?

Claude Code should connect to Sonnet via Amazon Bedrock without "Unexpected value(s) for the anthropic-beta header" error.

Error Messages/Logs

API Error: 400 {"error":{"message":"{\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\n    \"message\":\"Unexpected value(s) `tool-examples-2025-10-29` for the `anthropic-beta` header. Please \n    consult our documentation at docs.anthropic.com or try again without the \n    header.\"},\"request_id\":\"req_vrtx_011CV9FbW8EZVPrWadzgrzSS\"}. Received Model \n    Group=xxxx-bedrock-claude-4-sonnet\nAvailable Model Group \n    Fallbacks=None","type":"None","param":"None","code":"400"}}

Steps to Reproduce

1. Install and configure latest Claude Code.
2. Connect Sonnet via Amazon Bedrock.
3. Attempt to run any command that triggers API integration.
4. Observe 400 error regarding anthropic-beta header value.

Claude Model

_No response_

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

latest

Platform

AWS Bedrock

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

I'm using Amazon Bedrock integration with Sonnet model. Error appears with latest Claude Code. Please advise if anthropic-beta header should be set differently or if code update is needed for Bedrock integration. See error details above.