That's a really slick workflow and I totally agree that writing music is just listening to music in your head. :)

I write a lot of multi-part scores (i.e for big band and small jazz combos) and the idea of linting to check for things like note doubling or parallel fifths is a dream of mine.

When you say write parts of this composition into the script - what form does that take ? Is it midi ? Is it score data generate by a musescore plugin ? This workflow sounds amazing and I'm really curious how you get from point A to the intermediate point.