[BUG] VSCode "There's an issue with the selected model" With OpenRouter

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 the the VSCode Claude extension with OpenRouter keys (as described here), I always get this error message, regardless of which model I use:

There's an issue with the selected model (claude-opus-4-6[1m]). It may not exist or you may not have access to it. Run --model to pick a different model.

There's another issue that I thought was related to this, but downgrading to VSCode extension v2.1.77 did not resolve the issues.

When I use claude directly in the terminal, I still get the same issue. But by using /logout, when I restart claude, the issue is gone.

What Should Happen?

VScode Claude extension should work.

Error Messages/Logs

There's an issue with the selected model (claude-opus-4-6[1m]). It may not exist or you may not have access to it. Run --model to pick a different model.

Steps to Reproduce

1. Install Claude Code for VS Code in VS Code and setup an OpenRouter key as described here: https://openrouter.ai/docs/guides/coding-agents/claude-code-integration

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

VSCode extension v2.1.92

Platform

Other

Operating System

Ubuntu/Debian Linux

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_