This application basically serves to facilitate the programming of Construct3 plugins, creating "the skeleton" of the plugin, but you will need to know javascript to give functionality to your plugin.
There is a video that shows a little how it works. It is not difficult to create a plugin with this tool, but as I said before, you are the one who must give it the functionality you want.
Obviously, there the tool can't guess what you want to do, it can only offer you an editor where you can write the code.
Maybe continue updating the tool if you really find it useful, I don't promise anything :)
