Command line parameters for macOS?

I can't seem to find any documentation listing if there are any command line parameters for macOS. I can launch the application via the command line like:

open -a Mp3tag --args ??

or

/Applications/Mp3tag.app/Contents/MacOS/Mp3tag

Can we set the directory upon launching?

This is said in the documentation about the startup folder:

I meant can I set the directory via command line parameters.

Yes, you can just pass the directory to the open command, e.g.,

open -a Mp3tag "path/to/your/files"

Thanks!
What about the "/add" commands like you can do in Windows to add only certain directories?