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name: beatlab-contract description: BeatLab JSON contract for 16-step (0-15) pianoSequence & drumSequence. Use when generating or editing beats. user-invocable: false

BeatLab Contract (v1)

You must follow this exact contract (Mastra AI Beats Lab compatible):

• Steps: 16 (0-15)
• Output JSON must include:
  • "pianoSequence": object mapping each allowed note -> array of step numbers (0-15)
  • "drumSequence": object mapping each allowed drum sound -> array of step numbers (0-15)

Allowed piano notes (fixed): C5, B4, A4, G4, F4, E4, D4, C4, B3, A3, G3

Allowed drum sounds (fixed): Kick, Snare, HiHat, Clap, OpenHat, Tom, Crash, Ride, Shaker, Cowbell

Musical defaults (helpful heuristics):

• Kick often on 0 and/or 8
• Snare often on 4 and/or 12
• HiHat can be steady (e.g., every 2 steps) but avoid over-density
• Keep melody minimal (few notes, repeating motif)

Output should be ONLY JSON when asked for Beat JSON.