One of the nice things that you can do with it is write XAML FXCop rules. Now there has been a common ask of getting FXCop running on Xaml. Currently VS doesnt support this; but now you have the functionality at your tooltips. The toolkit has a Microsoft.Xaml.Tools.FxCop.dll which provides the base structure for your rules. So you could easily extend the inbuilt set of rules with that of your own.