anomalyco / anomalyco/opencode
GitHub Copilot grok-4.5 fails: not accessible via /chat/completions
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@jlongster is already working on this.
Since Aug 15, 2026.
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- TypeScript
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Description
Description
Selecting grok-4.5 through the GitHub Copilot provider fails immediately with:
GitHub Copilot only serves grok-4.5 on /responses. OpenCode still routes grok-* to /chat/completions. Same class of bug as #2758 (gpt-5-codex). The Copilot plugin currently sends only GPT-5+ models to Responses; grok-4.5 falls through to chat completions.
The same Copilot account can use Grok 4.5 in VS Code.
Plugins
None.
OpenCode version
1.16.2
Steps to reproduce
/connect→ GitHub Copilot/model→github-copilot/grok-4.5- Send any prompt
Screenshot and/or share link
N/A. Error text: model "grok-4.5" is not accessible via the /chat/completions endpoint
Operating System
Windows 10
Terminal
OpenCode desktop
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