Describe the bug

all models failed: error receiving from stream: HTTP 400: POST "https://api.githubcopilot.com/chat/completions": 400 Bad Request {"message":"model "gpt-5.3-codex" is not accessible via the /chat/completions endpoint","code":"unsupported_api_for_model"}

Version affected

$ docker-agent version
docker-agent version v1.40.0
Commit: Homebrew

How To Reproduce

1. Export the GITHUB_TOKEN env variable:

   $ export GITHUB_TOKEN=$(gh auth token)
   

2. Select the github-copilot/gpt-5.3-codex model
3. Ask anything to the agent
4. See error