I don't think you can. Nuke is not a command line tool like Shake so you can't feed node classes as command line arguments to create scripts on the fly.
A less elegant way would be to the [args n] command as an expression in an existing script to drive it via command line.
I.e.
You could use "[argv 0], [argv 1], [argv 2]" in a text node, then feed the required text via command line like this:
nuke -x
It's a pain in the butt though because all arguments have to start with a non-numerical character so if you want to drive numbers with it you have to prefix them with a letter in the command line and set up expressions in the script so that prefix is removed again in the knob.
Anyway, I think this is as close as you can get to command line comping a la Shake.
