The public OpenAPI file is at:

https://docs.h3hub.cn/openapi.public.json

It contains only core public API endpoints. /internal/*, /admin/*, and non-core account, billing, and community paths are excluded so web-only interfaces are not exposed.

You can import it into Postman or Insomnia, or let an agent read it to generate client code. It contains interface definitions, not real secrets.