Indeed, I am just trying to get the hang of it by looking at Response after sending Queries & Mutations by curl and in the GraphQL Playground to the API endpoint, as documented in Domain Reseller Guide that was announced here.
Also, I have been looking at GraphQL API client libraries that are written in Go, such as this one, which would go well together with the Terraform Provider SDK in Go…
Although Spacelift’s Terraform Provider uses another (older?) GraphQL API client library, this appears to be a neat way to build Terraform providers for platforms that expose GraphQL API endpoints, such as Fly.