It installs Visual Studio project templates to be used when creating projects from .NET Core 'dotnet new' command line interface. Currently, it contains a project template for a NSpec test library targeting both .NET Core and .NET Frameowrk. NOTE: Even if template currently creates a project supporting .NET Core Tools Preview 2 (the one based on project.json), in order to install custom CLI templates like this you need to have at least .NET Core Tools RC4 on your development machine.