how do i bind a flags enum in asp.net core mvc

I found one asp.net docs page that referenced AddFlagsEnumModelBinderProvider as an options value for services.AddMvc(), but when I tried to implement that in aspnetcore 1.0.1, that options value was not available with Intellisense.

is this rookie error?

or is this another symptom of docs and samples for asp.net core that are still on the backlog?