In the VCV world, you’d feed it input – i.e. jamming on a keyboard, and at a certain point flip a switch and it would use Markov chains to randomly generate output note sequences, that randomly selects a note, and generates a note after it based on the probability in the input that a particular note follows after it.
This is what’s behind ‘travesty’ generators do with text, but do it with notes or groups of notes.
There’s a lot of Markov chain code floating around, e.g.
Isn’t this what “Doctor Chainikov” does? Is that module still around? Oh, I see, that’s the link above. In any case it’s a fine Idea. I read about doing this in an 80’s issue of Computer Music Journal. Tried it out in the 90’s. It works pretty good. Order 1 sounds pretty random, Order 3 plays whole sections of the input music. Order 2 seemed pretty good to me.