c.IncludeXmlComments(string.Format("{0}/bin/ThinkingSpace.XML", System.AppDomain.CurrentDomain.BaseDirectory));

private static string GetXmlCommentsPath()
{
  return $@"{System.AppDomain.CurrentDomain.BaseDirectory}\bin\GetDocumentation.XML";
}

using System;
using System.IO;
using System.Web;
using System.Web.Http;
using System.Web.Http.Description;
using System.Web.Http.Dispatcher;
using System.Web.Routing;
using Swagger.Net;

[assembly: WebActivator.PreApplicationStartMethod(typeof(ThinkingSpace.App_Start.SwaggerNet), "PreStart")]
[assembly: WebActivator.PostApplicationStartMethod(typeof(ThinkingSpace.App_Start.SwaggerNet), "PostStart")]
namespace ThinkingSpace.App_Start 
{
  public static class SwaggerNet 
  {
    public static void PreStart() 
    {
      RouteTable.Routes.MapHttpRoute(
        name: "SwaggerApi",
        routeTemplate: "api/docs/{controller}",
        defaults: new { swagger = true }
      );      
    }
    
    public static void PostStart() 
    {
      var config = GlobalConfiguration.Configuration;

      config.Filters.Add(new SwaggerActionFilter());
      
      try
      {
        config.Services.Replace(typeof(IDocumentationProvider),
          new XmlCommentDocumentationProvider(HttpContext.Current.Server.MapPath("~/bin/ThinkingSpace.XML")));
      }
      catch (FileNotFoundException)
      {
        throw new Exception("Please enable \"XML documentation file\" in project properties with default (bin\\ThinkingSpace.XML) value or edit value in App_Start\\SwaggerNet.cs");
      }
    }
  }
}