Agent grammar subset

Lines a co-DJ lane may emit.

The lines a co-DJ lane may emit. Human/host stream lines are read-only context; you add new tracks + patterns on your own lane only (ids prefixed with your actorId, e.g. ai-a_hat). This is the agent subset of the full language — for the complete grammar (master-scope headers, clips, gen_block graphs, automation, control directives) see @spacedevin/deck grammar (canonical). Deckard UI / ownership notes: DECK_GRAMMAR.md. Keep this in lockstep with the agent SYSTEM_PROMPT in services/agent-worker/main.tish and the master-scope denylist in src/codj/Skills.tish.

Track block

track <DisplayName> id <lane_unique_id> gen <generator> [* <bars>]
  mix gain <0..1> pan <-1..1> [eq_lo <dB>] [eq_mid <dB>] [eq_hi <dB>] [mute 1] [solo 1]
  fx [cutoff <hz>] [res <0..1>] [drive <0..1>] [reverb_send <0..1>] [lfo_rate <hz>] [lfo_depth <0..1>] [filter_type <lowpass|highpass|bandpass|notch>]
  voice [octave <-2..2>] [chord <off|major|minor|min7|maj7|dom7|sus4|add9|dim|aug>] [arp <off|up|down|updown|random>] [arprate <auto|1/8|1/16|1/32>] [inversion <root|1st|2nd>] [strum <0..150>]
  …generator param lines (see below)…
  adsr a <s> d <s> s <0..1> r <s>          (generators with an envelope)
  step_pitch <midi>                         (base pitch for step hits; default 36; `bar <selector>` for per-bar)
  steps <16 x/. tokens>  |  steps euclid <hits> 16
  step_vel <16 ints 1-127>                  (per-step velocity lock — optional, emit only deviations)
  step_prob <16 floats 0-1>                 (per-step probability — seeded, deterministic across peers)
  step_ratchet <16 ints 1-8>                (per-step sub-hits)
  step_nudge <16 floats -0.5..0.5>          (per-step micro-timing, fraction of a step)
  note <midi> <startBeat> <durBeats> v <vel 0-127> [p <prob>] [r <ratchet>] [n <nudge>] [bar <sel>]   (repeat; melodic)
  loops <N|inf>                             (finite repetition cap for this channel)

Beats are quarter-notes: step i (0–15) = beat i0.25 in the looping bar. <bars> on the header makes a multi-bar pattern; bar <selector> (even/odd/<n>/2n+1/0,2) on note/step_pitch varies it per bar.

Generators (gen <id>)

Fixed generators (33) — pick by role; don't default everything to noise_burst/fm:

Macro voices (expand to a tuned patch; use the macro name directly as gen <id>):

Generators vs. macros never share a label (see project memory macro-generator-boundary-policy). Only noise_burst/fm/basic_osc/matrix_fm/drum_synth/patch have short aliases — every other id is used verbatim.

Generator param lines

What you may NOT emit (master-scope)

These change the whole session for every player, so they require the master_mixer skill and are skipped for an agent lane (per Skills.tish):

bpm   tpl   auto   transpose   scale   swing   master_mix   actor_mix
session_scenes   session_slot   clip   @ <control directives>

Also never emit remove_track <id> — deleting tracks is a host/UI action (owner-gated), not something an agent does. You add complementary parts.

So global key (scale) and groove (swing) are master-only — you cannot re-key or re-shuffle the mix. Live control directives (@ launch/transport/cue/throw/fx/deck) are a separate master/owner surface — see package grammar § Control directives.

Streaming

You may stream deck.line incrementally — each line decodes progressively (a track sounds the moment its track … arrives; the pattern fills as steps …/note … stream). Lane-unique ids are required.

Goal: complement the project — add the parts that are missing (hats, perc, bass, chords, melody), match the tempo, and leave space. Don't double what already plays.