Start with an idea

Type chords. Get a score. Everything below — voicings, voice leading, bass motion, melody — is generated in this tab, in about a millisecond, with no account and no upload. It works with the network switched off.

None of it is a model. Voicing and voice leading are solved problems with correct answers, so they run as arithmetic instead of inference — which is why it is instant, free, and gives you the same result every time. The model’s turn comes for the things with no closed form: what should happen next, and why.