NodeCanvas is built to work with any type you may need. To depict this within the editor though, keeping it clean and not cluttered by the thousands of possible types available, a custom editor window called Preferred Types Editor exists, within which you can restrict the types that will be shown within various menus when working with NodeCanvas. Specifically, the cases where this list will come into use, include:
Opening the Preferred Types Editor can be done through the “Tools/ParadoxNotion/NodeCanvas/Preferred Types Editor” unity top menu. As you will find out, there are a number of types already in the list by default, but feel free to modify the list however you see fit for your project.
This editor and its use is strictly an editor thing for faster workflow and has nothing to do with runtime.