compose

name	compose
description	Create and edit MIDI files. Add notes, change tempo and time signature, transpose, quantize, and save.

/compose — Create & Edit MIDI Files

Use the Mozart Pi tools to create MIDI files from scratch or edit existing ones.

Quick Start

/compose new_song.mid

Creating a New MIDI File

1. Create with mozart_create_midi — set name, tempo, time signature
2. Add tracks with mozart_add_track — name them and assign instruments
3. Add notes with mozart_add_notes — specify measure, beat, pitch, duration, velocity
4. Save with mozart_save_midi — write to disk

Editing an Existing File

1. Load with mozart_load_midi
2. Browse with mozart_get_measures to understand the structure
3. Edit — use mozart_add_notes, mozart_delete_notes, mozart_transpose, mozart_quantize
4. Change tempo/time sig with mozart_set_tempo, mozart_set_time_signature
5. Save with mozart_save_midi

Examples

Create a simple melody

mozart_create_midi alias="demo" name="Demo Song" bpm=120 file_path="demo.mid"
mozart_add_track alias="demo" name="Piano" instrument=0
mozart_add_notes alias="demo" track=0 notes=[
  {"measure": 1, "beat": 1, "note_name": "C4", "duration_beats": 1, "velocity": 80},
  {"measure": 1, "beat": 2, "note_name": "E4", "duration_beats": 1, "velocity": 80},
  {"measure": 1, "beat": 3, "note_name": "G4", "duration_beats": 1, "velocity": 80},
  {"measure": 1, "beat": 4, "note_name": "C5", "duration_beats": 1, "velocity": 90}
]
mozart_save_midi alias="demo"

Transpose a track up a perfect fifth

mozart_transpose alias="song" track=0 semitones=7

Quantize to eighth notes

mozart_quantize alias="song" track=1 grid_beats=0.5

Delete notes in measures 5-8 and rewrite

mozart_delete_notes alias="song" track=0 measure_start=5 measure_end=8
mozart_add_notes alias="song" track=0 notes=[...]
mozart_save_midi alias="song"

Change tempo mid-song

mozart_set_tempo alias="song" bpm=140 at_tick=1920

Tool Reference

Tool	Purpose
mozart_create_midi	Create a new empty MIDI file
mozart_add_track	Add a track with name and instrument
mozart_set_instrument	Change a track's instrument
mozart_add_notes	Insert notes at measure/beat positions
mozart_delete_notes	Remove notes from a measure range
mozart_transpose	Shift notes up or down by semitones
mozart_quantize	Snap notes to a rhythmic grid
mozart_set_tempo	Set/change tempo at a tick position
mozart_set_time_signature	Set/change time signature
mozart_save_midi	Write MIDI file to disk

General MIDI Instruments (Common)

#	Instrument	#	Instrument
0	Acoustic Grand Piano	24	Nylon Guitar
4	Electric Piano 1	25	Steel Guitar
6	Harpsichord	30	Distortion Guitar
11	Vibraphone	32	Acoustic Bass
13	Xylophone	33	Electric Bass (finger)
16	Drawbar Organ	40	Violin
19	Church Organ	42	Cello
21	Accordion	46	Orchestral Harp
56	Trumpet	73	Flute
60	French Horn	71	Clarinet
65	Alto Sax	68	Oboe

Tips

• Note names follow scientific pitch notation: C4 is middle C
• Beats are 1-based within a measure (beat 1 = downbeat)
• Fractional beats work: beat 1.5 = the "and" of beat 1
• Velocity ranges from 1 (barely audible) to 127 (maximum)
• Always mozart_save_midi after editing — changes are in-memory until saved
• Use mozart_get_measures to verify your edits look correct before saving