Hey, thanks for the report with details and the Request ID. This is a bug on our side. For BYOK Gemini 3.x via AI Studio and OpenRouter, Cursor is currently sending disable_thought_tag in extra_body. Those providers don’t recognize it and reject the request with a 400. We’re already tracking this issue, but I can’t share an ETA yet.
While we’re fixing it, here are a couple workarounds:
- Use the built-in Gemini in Cursor without BYOK.
- If you have access to Vertex AI, connect via a Vertex key. That code path isn’t affected.
Related thread with the same root cause is here: Gemini API key not working in Cursor, getting PROVIDER_ERROR
You can subscribe there and we’ll post updates about the fix. If it gets worse or you see new symptoms, let me know.