Files.GetDirectory root path

I’m trying to use json-rpc to browse the top of the “files” tree like in the File Manager with Files.GetDirectory(media=files, path=?).
Does anyone know what the magic path for the top of the files sources is?

For videos the “media” parameter is “video” and the path is “library://”.
I then get back the top of the video tree with: Files, Video Addons, Playlists, Recently Added Episodes etc.