c# - ASP.NET Web Api Help Page doesn't show any tips -

i have working pages (start mvc 4 project , web api) , enable documentation , still working. working time , @ api , see this:

i can't find out change cause this. tried reinstall package pages didn't help. can cause this? how fix it?

edit:

helppagearearegistration:

public class helppagearearegistration : arearegistration     {         public override string areaname         {                         {                 return "helppage";             }         }          public override void registerarea(arearegistrationcontext context)         {             context.maproute(                 "helppage_default",                 "help/{action}/{apiid}",                 new { controller = "help", action = "index", apiid = urlparameter.optional });              helppageconfig.register(globalconfiguration.configuration);         }     } 

web api routes registration same default.

public static class webapiconfig {     public static void register(httpconfiguration config)     {         config.routes.maphttproute(             name: "defaultapi",             routetemplate: "api/{controller}/{id}",             defaults: new { id = routeparameter.optional }         );          // uncomment following line of code enable query support actions iqueryable or iqueryable<t> return type.         // avoid processing unexpected or malicious queries, use validation settings on queryableattribute validate incoming queries.         // more information, visit http://go.microsoft.com/fwlink/?linkid=279712.         //config.enablequerysupport();          // disable tracing in application, please comment out or remove following line of code         // more information, refer to: http://www.asp.net/web-api         // config.enablesystemdiagnosticstracing();     } } 

edit2:

example of apicontroller:

public class citycontroller : apicontroller {     private icityrepository cityrepository;      public citycontroller(icityrepository repository)     {         cityrepository = repository;     }      /// <summary>     /// cities database     /// </summary>     /// <returns>all cities</returns>     [outputcache(cacheprofile = "cache1hour")]     public ienumerable<city> get()     {         return cityrepository.getallcities();     } } 

weekmenucontroller:

public class weekmenucontroller : apicontroller {     private weekmenurepository repo;      public weekmenucontroller()     {         repo = new weekmenurepository();     }     ... 

restaurantcontroller:

public class restaurantcontroller : apicontroller {     private restaurantrepository _repo;      public restaurantcontroller()     {         _repo = new restaurantrepository();     }     ... 

daymenucontroller:

public class daymenucontroller : apicontroller {      private daymenurepository repo;      public daymenucontroller()     {         repo = new daymenurepository();     }     ... 

actionrepository:

public class actioncontroller : apicontroller {     private iactionrepository _repository;      public actioncontroller(iactionrepository repository)     {         _repository = repository;     }     ...