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madisonrickertmadisonrickert/ableton-tools/skills/als-build/SKILL.md

als-build

Skill16 starsChanged 37 days agoMITView on GitHub

Build and organize an Ableton Live session from the command line — set the tempo, add bare tracks, fold tracks into real group folders (routed to the group bus), mute tracks, snap every warped stem to the master's position and warp map (sync-to-master), and copy proven device chains from other projects (transplant-devices, experimental). Use when assembling a project from stems, organizing tracks into groups, fixing stems that are offset from the master clip, or giving a new session a head start with device chains from past sets. All edits are validated, dry-run by default, and auto-backup before committing.

The file

We split this skill into the rules it gives an agent

5 rules. About 0 are common, 1 is distinctive, and 4 are very specific to this project.

  • ≈0

    Common · estimate

    Many files like this have a rule of this kind.

  • ≈1

    Distinctive · estimate

    This author's own choices. Worth a look.

  • 4

    Very specific

    Tied to their project's names, files or tools. Probably skip.

  • Common
  • Distinctive
  • Very specific
  1. Distinctive:

    Never re-warp just the master in Live and leave the stems.

    line 45
  2. Very specific:

    Use --to-main for mastering chains and --mode append to add to an existing chain.

    line 61
  3. Very specific:

    Run ableton als validate FILE.als --json after a sequence of commits.

    line 66
  4. Very specific:

    Run ableton warp-check FILE.als (experimental) to confirm warped clips share the master's map and that its markers sit on the beats.

    line 67
  5. Very specific:

    Ask the user to open the set in Live.

    line 69

≈ “Common” is an estimate: at least 1 in 5 of the 350,495 skill files we read have a rule of the same kind, not the same words. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.

Keep what fits and drop the rest. Your version, ready for your agents.
Files
SKILL.md

You assemble and organize .als sessions with the bundled engine (the ableton command on PATH; see the engine skill). Every command is a dry-run until --commit, and its JSON includes a validation report. Close Ableton before committing. The commit refuses while Live is running, because Live's next save would silently discard the edit.

Typical order when building from stems:

  1. als import-stems (see the als-files skill);
  2. group, add-track, mute;
  3. sync-to-master if the user moved the master clip in Live;
  4. transplant-devices;
  5. als validate.

Commands

NeedCommand
Project tempoableton als set-tempo FILE.als 133.9 [--commit]
Bare track for a new recordingableton als add-track FILE.als --name "SAX (live layer)" [--color 25] [--after master]
Group folderableton als group FILE.als --name WORDS --tracks "vocals" "lead v1" … [--color 20]
Mute / unmuteableton als mute FILE.als --tracks "guitar" "strings" [--unmute]
Stems out of positionableton als sync-to-master FILE.als --master master --all-warped [--markers]
Reuse a device chainableton als transplant-devices FILE.als --from OTHER.als --src-track Sax --to-track "SAX (live layer)"

Notes:

  • Track names accept the exact name, the name without Live's <index>- prefix, or the Id.
  • group members must be contiguous and not already grouped. It inserts a Live 12 group-track template: use it on Live 12 sets only.
    • The group gets TrackGroupId, and every member is routed to the group bus. Without that routing they would only look grouped.
    • Sends and slots adapt to the set's returns and scenes.
  • add-track creates a track with no clips, devices, automation, frozen audio or take lanes, at default volume, pan and sends. It is never inserted inside a group.
  • sync-to-master copies the master clip's Arrangement position (the Time attribute, CurrentStart/End and loop bounds) onto every warped stem clip.
    • Without --markers, diff.marker_mismatch lists stems whose warp map differs from the master's, i.e. stems that would drift.
    • --markers copies the master's warp map too.
    • Never re-warp just the master in Live and leave the stems; run this afterwards.

  • transplant-devices is experimental. It copies a chain, plugin state included, from another set:

    • it fixes ids;
    • it remaps the chain's own internal routing;
    • it resets sidechains that pointed at other tracks to None (diff.routing_reset). Tell the user to re-assign them, or pass --map-track SourceTrack=TargetTrack;
    • it drops the source's automation of those devices (--with-automation keeps it);
    • it copies any project sample the chain uses into Samples/Imported/ (only once the commit is allowed; a different file with the same name gets <name> (2).<ext>);
    • it reports plugins and whether each one is installed (diff.plugins).

    Use --to-main for mastering chains and --mode append to add to an existing chain. It has been verified on 2,108 real chains, but tell the user to check the result in Live.

Verify

  • Run ableton als validate FILE.als --json after a sequence of commits.
  • Run ableton warp-check FILE.als (experimental) to confirm warped clips share the master's map and that its markers sit on the beats.
  • Ask the user to open the set in Live. If Live reports an error, paste it back. Structural errors also show up in als validate.

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