- Introspection (__schema queries) for every graphQL server. You can even see what it exposes because most services expose a web playground for testing graohQL APIs, e.g. GitHub: https://docs.github.com/en/graphql/overview/explorer
- Server Reflection for gRPC, though here it's optional and I'm not aware of any hosted web clients, so you'll need a tool like gRPCCurl if you want to see how it looks in real services yourself.
- OpenAPI is not a protocol, but a standard for describing APIs. It is the list-tools for REST APIs.
- Introspection (__schema queries) for every graphQL server. You can even see what it exposes because most services expose a web playground for testing graohQL APIs, e.g. GitHub: https://docs.github.com/en/graphql/overview/explorer
- Server Reflection for gRPC, though here it's optional and I'm not aware of any hosted web clients, so you'll need a tool like gRPCCurl if you want to see how it looks in real services yourself.
- OpenAPI is not a protocol, but a standard for describing APIs. It is the list-tools for REST APIs.