[BUG] Desktop app hangs when Bedrock model unavailable (403), cannot switch model

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 using Claude Code Desktop with AWS Bedrock and a model that isn't available on the account (e.g., claude-opus-4-8),
the app:

1. Shows error: API Error: 403 anthropic.claude-opus-4-8 is not available for this account
2. Becomes unresponsive — cannot type /model command to switch to an available model
3. Only way out is force-quit

Expected behavior: After a 403 "model not available" error, the app should remain responsive and allow switching to a
different model via /model.

Environment:

• Claude Code Desktop (macOS)
• AWS Bedrock endpoint (eu-central-1)
• Opus 4.5 available, Opus 4.8 not available

What Should Happen?

Expected behavior: After a 403 "model not available" error, the app should remain responsive and allow switching to a
different model via /model.

Error Messages/Logs

Steps to Reproduce

1. Configure Claude Code Desktop to use AWS Bedrock (eu-central-1) as the API endpoint
2. Have an AWS account where claude-opus-4-8 is NOT enabled, but claude-opus-4-5 IS enabled
3. Start Claude Code Desktop (it defaults to opus-4-8)
4. App attempts to connect and receives 403: "anthropic.claude-opus-4-8 is not available for this account"
5. Try to type /model opus in the input field to switch to available model
6. App is unresponsive — input field doesn't accept text, no way to switch model
7. Only option is Cmd+Q to force-quit

Expected: After 403 error, input field should remain active so user can run /model command to switch to an available model
(e.g., opus-4-5)

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Version: 2.1.220

Platform

AWS Bedrock

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_