i wanted to learn trumpet, and i really love chet baker.

so i asked codex to find transcriptions of his solos.

that turned into a much bigger project than i expected.

it searched musicians' websites and academic jazz archives, found legitimate sheet music and midi files, verified which recordings actually contained trumpet solos, and converted everything into notation for b♭ trumpet.

one midi had more than 2,000 guitar notes. codex identified the actual trumpet part instead.

for solos that were only visible in publicly available videos, it reconstructed the notation and credited the original arrangers.

then i kept asking for things:

show me the valve fingerings. let me change the key and tempo. explain scales like i'm a beginner. give me an actual learning path. loop the hard parts. add walking bass and backing tracks. build me a 10-minute practice session.

now i have a personal chet baker practice app with ten playable pieces, guided lessons, phrase looping, and three different backing bands.