Steer a music composition with enum labels

01 · Role in the system

What Jev does here

Across eight allowlisted typed operations, Jev picks the composition's character, form, key, meter, texture, palette, tempo, dynamics, instrument, and per-phrase harmony-book entries from closed enums, and the trolley demo adds table Choices, difficulty and absurdity Scores, and a Noul on what most people would pull. No operation ever emits notes or sentences; a pure renderer expands the plan into chords, a VexFlow engraving, audio, and MIDI, and the plan JSON stays editable so listeners can hear a single label change.

A plan made only of closed vocabulary

The composition never touches a note. Jev picks character, form, key, meter, texture, palette, tempo, dynamics, instrument, and per-phrase harmony entries from closed enums across eight allowlisted typed operations — and then a pure renderer the model knows nothing about expands that plan into chords, engraving, audio, and MIDI. The seam is the design: a plan of labels is auditable, editable, and diffable in a way generated music is not.

The trolley variant shows the same shape carrying non-musical judgments — table choices, difficulty and absurdity scores, and a Noul on what most people would pull. The record is explicit that neither demo makes quality or alignment claims; what it demonstrates is typed planning as an interface, where a single label change is something a listener can hear.

Small server, honest edges

The server accepts only the eight typed operations, and its rate limit is in-memory, resetting on every serverless cold start — the kind of infrastructure honesty most demos leave out of their READMEs.

As music-cluster evidence, this record and the note-by-note composer bracket the approach: one plans with labels, the other chooses every note. Both bound the model to preference among code-enumerated options; neither pretends the output has been evaluated.

02 · Control boundary

Where Jev sits

A style string to a plan of typed enum judgments; a deterministic render seam turns the plan into score, audio, and export without knowing about the model.

Code owns the loop, permissions, thresholds, validation, and side effects. Jev owns only the bounded judgments described above.

03 · Known limits

What this evidence does not prove

• Musical and trolley outcomes are demonstrations of typed planning, not evaluated quality or alignment claims.
• The server accepts only the eight typed operations, and its in-memory rate limit resets on every serverless cold start.

04 · Attribution

Public sources

This is a Community record: the project was published by a third-party community author.

• wustep ↗Community · github · public · checked 2026-09-18