Cursor
Cursor's BYOK is OpenAI-compatible only. It verifies the endpoint by
calling the models list and expecting a 200 — which OpenGateway
returns for any valid-looking key.
Set the base URL
Go to Settings → Models → API Keys → Override OpenAI Base URL:
Base URL: https://api.opengateway.one/oss/v1 API key: YOUR_KEY
- Cursor calls
GET /oss/v1/modelsto verify. OpenGateway returns the OpenAI list shape with200, so verification passes. - Add a model with + Add Custom Model, e.g.
claude-sonnet-4-7or a raw id likeQwen/Qwen3-Coder-480B-A35B-Instruct:fastest.
The base-URL override is global and also reroutes Cursor's own models; Cursor periodically auto-disables the toggle, so re-enable it as needed.
Vision/multimodal requests hit a hardcoded api.openai.com validation in Cursor that ignores the override — text works, images may not. This is a Cursor-side limitation, not a gateway one.
Why the 200 matters
See Model discovery for why the
200 requirement exists and how the dual-shape endpoint satisfies
both OpenAI and Anthropic clients from one path.