ASP .NET controller to monitor currently registered routes

MonitorController.cs

using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.ActionConstraints;
using Microsoft.AspNetCore.Mvc.Infrastructure;

// namespace here

[ApiController]
[Route("api/[controller]")] // update route with your preference here
public class MonitorController : ControllerBase
{
    [HttpGet]
    [HttpOptions]
    [Produces(MIME.TXT)]
    public string Index() => "ok";

#if DEBUG

    [HttpGet(nameof(Routes))]
    public IEnumerable<object> Routes([FromServices] IActionDescriptorCollectionProvider actionsDesc)
    {
        return actionsDesc.ActionDescriptors.Items
            .Where(ad => ad.AttributeRouteInfo is not null)
            .Select(ad =>
                new
                {
                    methods = string.Join('|', ad.ActionConstraints?
                        .Where(c => c is HttpMethodActionConstraint)
                        .SelectMany(c => (c as HttpMethodActionConstraint)!.HttpMethods)
                        ?? Enumerable.Empty<string>()),
                    ad.AttributeRouteInfo!.Template,
                    ad.AttributeRouteInfo!.Name,
                    ad.DisplayName
                }
            );
    }

    [HttpGet(nameof(Throw))]
    public IActionResult Throw()
    {
        throw new Exception("this is a test exception");
    }

#endif
}