ResponseGraphType.cs

public class ResponseGraphType<TGraphType> : ObjectGraphType<Response> where TGraphType : GraphType
{
    public ResponseGraphType()
    {
        Name = $"Response{typeof(TGraphType).Name}";

        Field(x => x.StatusCode, nullable: true).Description("Status code of the request.");
        Field(x => x.ErrorMessage, nullable: true).Description("Error message if requests fails.");

        Field<TGraphType>(
            "data",
            "Data returned by query.",
            resolve: context => context.Source.Data
        );
    }
}