MVC 6 integrated help missing in visual studio 201

Question

This is such a pathetic question to ask here, but I'm out of ideas. I've recently had cause to start experimenting with a Web API project using MVC 6 in Visual Studio 2015. It's all very new to me, and I've wanted to look at the associated help for a number of classes, properties, attributes, and so on. But the F1 integrated help, local or web based, always comes up "cannot find". Even on a simple/central class like Controller, it looks up the help id MICROSOFT.ASPNET.MVC.CONTROLLER and finds nothing. I've poked around in VS installation, looked for external installs, searched here and across google, all to no benefit. No matter how I try to constrain the results, the vast majority of hits are people trying to create dynamic help for APIs. If it's a duplicate, I'll be very happy to be pointed to any answer.

How do I add integrated help for MVC 6 Web API to VS2015? Baring that, is there a better reference than just drilling down through the related MS web site?