mcp_opendaw_create_arrangement_variation
Create musically varied song sections with per-track transformations: adjust drum density, shift bass octaves, transform melodies, and include or skip tracks to build breakdowns, bridges, and drops.
Instructions
Create a musically varied section — not a repeat, a real variation.
Unlike create_genre_sections (which repeats the same loop at different velocities), this tool applies actual musical transformations to each track independently:
Drums: density control (0.3 = sparse, 1.0 = full, 1.5 = busy with ghosts)
Bass: octave shift (bass_octave_shift = +1/-1/-2)
Melody: inversion, transposition, retrograde, or fragment
Track inclusion: skip drums/bass/harmony/melody independently
This lets you build a song where each section has real musical variation, not just energy changes. The drop has full drums, the breakdown has inverted melody + no bass, the bridge has sparse drums + octave-up bass.
genre: Any of the 14 arrangement genres (dnb/house/trap/techno/dubstep/ synthwave/trance/disco/afrobeat/rock/jazz/pop/funk/reggae). section_name: Label for this section (e.g. "verse2", "bridge", "drop2"). bpm: Override tempo (None = genre default). root: Override key (None = genre default). bars: Section length in bars (4-32, default 8). start_beat: Where this section starts in the timeline. velocity: Base velocity 0-1. drum_density: 0.3 = sparse (half notes removed), 1.0 = normal, 1.5 = busy (extra ghost notes between hits). bass_octave_shift: 0 = normal, +1 = octave up, -1 = octave down, -2 = sub. melody_transform: "none", "invert", "transpose:5", "transpose:-7", "reverse", "fragment", "octave_up", "octave_down". include_drums/include_bass/include_harmony/include_melody: Set False to skip that track (e.g. breakdown = no drums, no bass).
Returns notes per track and transformations applied.
Example:
Breakdown section: sparse drums, no bass, inverted melody
create_arrangement_variation("dnb", section_name="breakdown", drum_density=0.3, include_bass=False, melody_transform="invert", velocity=0.6)
Bridge: octave-up bass, retrograde melody
create_arrangement_variation("house", section_name="bridge", bass_octave_shift=1, melody_transform="reverse", start_beat=64, bars=4)
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| bpm | No | ||
| bars | No | ||
| root | No | ||
| genre | Yes | ||
| velocity | No | ||
| bass_track | No | ||
| drum_track | No | ||
| start_beat | No | ||
| unit_index | No | ||
| drum_density | No | ||
| include_bass | No | ||
| melody_track | No | ||
| section_name | No | variation | |
| harmony_track | No | ||
| include_drums | No | ||
| include_melody | No | ||
| include_harmony | No | ||
| melody_transform | No | none | |
| bass_octave_shift | No |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |