{"drum_kits":["trap","live","electronic","chiptune","lo-fi"],"gm_drum_map":{"kick":36,"kick2":35,"snare":38,"snare2":40,"hihat":42,"hihat_o":46,"hihat_p":44,"clap":39,"clave":75,"tom_low":41,"tom_mid":45,"tom_high":48,"ride":51,"crash":49,"splash":55},"melodic_instruments":["acoustic_bass","analog_lead","atmospheric","brass_section","electric_bass","electric_piano","glass_chord","organ","plucked_guitar","string_ensemble","sub_bass","synth_bass","synth_pluck","warm_pad"],"gm_melodic_map":{"electric_bass":33,"acoustic_bass":32,"synth_bass":38,"sub_bass":39,"warm_pad":89,"string_ensemble":48,"analog_lead":80,"synth_pluck":83,"electric_piano":4,"organ":16,"glass_chord":91,"atmospheric":90,"brass_section":61,"plucked_guitar":25},"chiptune_kits":["chiptune-nes","chiptune-gameboy","chiptune-arcade"],"payload_shapes":{"drum":{"description":"Step-grid drums. Each pattern row is a 0/1 list at 16 steps per bar (16th notes). Rows shorter than the song tile/loop automatically; row names come from gm_drum_map.","example":{"type":"drum","kit":"trap","velocity":100,"pattern":{"kick":[1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0],"snare":[0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0],"hihat":[1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0]}},"limits":{"max_steps_per_row":4096},"valid_row_names":["clap","clave","crash","hihat","hihat_o","hihat_p","kick","kick2","ride","snare","snare2","splash","tom_high","tom_low","tom_mid"]},"melodic":{"description":"Explicit notes. 'pitch' is an integer MIDI pitch 0–127, 'start' is in beats, 'duration' is in SECONDS (not beats), 'velocity' is 1–127.","example":{"type":"melodic","instrument":"analog_lead","notes":[{"pitch":57,"start":0,"duration":0.5,"velocity":90}]},"limits":{"max_notes":2048},"valid_instruments":["acoustic_bass","analog_lead","atmospheric","brass_section","electric_bass","electric_piano","glass_chord","organ","plucked_guitar","string_ensemble","sub_bass","synth_bass","synth_pluck","warm_pad"]},"chord":{"description":"Chord blocks. 'root' is a note name plus quality (e.g. 'Am7', 'Fmaj', 'Gsus4'); 'start' and 'duration' are both in beats.","example":{"type":"chord","instrument":"warm_pad","progression":[{"root":"Amin","start":0,"duration":8,"velocity":70}]},"limits":{"max_progression":512},"valid_qualities":["maj","min","7","m7","maj7","dim","m7b5","aug","sus4","sus2"]},"song_mode":{"description":"Set mode='song' (or arrangement_mode=true) and omit instruments to have the server compose a full sectioned arrangement: drums, bass, chords, lead motifs, and textures. Optional inputs: target_duration_seconds, key_signature, energy (0–1), sections, kit, chiptune, instrument_palette.","example":{"mode":"song","tempo":124,"key_signature":"A minor","target_duration_seconds":160,"genre":"darkwave"}}}}