Helper understanding withopenapi deprecation

[colin-s-ingram]

Hi we have a project where we are currently using Nswag. We have been using WithOpenApi and using it per endpoint to decorate the api docs with descriptions.

With the announcement here:
https://learn.microsoft.com/en-us/dotnet/core/compatibility/aspnet-core/10/withopenapi-deprecated
we were exploring switching to AddOpenApiOperationTransformer.

We added this to our minimal api but the summary and description are not added to the generated document.

 builder
     .MapGet("/something/{id}", Handler.HandleSomething)
     .AddOpenApiOperationTransformer (o,c,ct) =>
     {
         o.Summary = "Some Text";
         o.Description = "Some description";
         return System.Threading.Tasks.Task.CompletedTask;
      }

The only way we could achieve this is by adding the attribute following to the handler method.

[OpenApiOperation(
summary: "Something",
description: "Something"
)]

Since the attribute usage is only on [AttributeUsage(AttributeTargets.Method)] using something like below on the delegate also doesn't appear to work.

builder
     .MapGet("/something/{id}", Handler.HandleSomething)
     .WithMetadata(new OpenApiOperationAttribute("something", "something"))

The document says if we "used NSwag for document generation, use the IOperationProcessor API." I having a hard time understanding how in a nice minimal api friendly way I can use this to do the per endpoint specific documentation. It seems to me that I have register very specific operations far form the endpoint definition itself upon registering openApi.

Can anyone help me out and explain what our options are, and perhaps point me in the direction of documentation that would allow me fix this, Thanks in advance.