Groups Compose Agent Skill

When to propose

• 3+ nodes share a clear semantic tie (same scene, same character, same beat)
• The relationship would be obvious to a reader within 2 seconds of scanning the canvas
• You can write a ≤ 30-character title that names the tie

Skip if fewer than 3 members or the tie is just generation order.

Contract

• Use canvas_layout.js to write member positions and groupFrames in one atomic sidecar update.
• Never write or edit workflow.json; never put x / y into node data.
• A layout change may move member nodes when that makes the canvas clearer.
• The frame's geometry (x, y, width, height) is a bounding box computed from the final member positions.
• A node may appear in at most one frame; evict it from old frames in the same update.
• No nested frames.
• frameId: frame_<unix_ms>. Titles ≤30 chars recommended.

Patterns

Pick the one that fits. Grouping is current canvas state; read workflow.json per the project PROJECT_AGENT.md § "Choosing context" to verify ids.

1. Scene grouping

• Triggers: 3+ prompt/note/image/video nodes around one location, beat, or plot point.
• Title: Scene <N> — <location or beat>.
• Typical size: 3–8 members.
• Members: prompt/shot/image_result/video_result plus scene-scoped notes.
• Layout: place the script/shot note on the left, then images/videos in reading order to the right. Put attached voice/audio below the source card.

2. Character-reference set

A character card + its reference images.

• Triggers: ≥2 images of the same character.
• Title: <Character name> — references.
• Typical size: 2–6 images.
• Members: any image_result nodes depicting the same character.
• Layout: hero/reference card first, variations in a compact grid, attached voice node below.

3. Act / beat grouping

• Triggers: the user framed the session at act/beat granularity ("everything for act 2", "the whole chase sequence", "opening titles").
• Title: Act <N> or beat name.
• Typical size: 8–15 members. If larger, prefer splitting into scene subgroups instead.
• Members: all nodes that belong to that act/beat, spanning multiple scenes.
• Layout: arrange scene clusters left-to-right in story order, with enough gutter that frames do not overlap.

4. Production-state grouping (opt-in)

• Use only when user explicitly sorts by quality/status: approved, draft, rejected, WIP, final.
• Title: one status word.
• Typical size: open-ended.

Recipe

• Read ./workflow.json + ./canvas_positions.json. workflow.json gives you node ids + labels + subtypes; canvas_positions.json gives you each node's x / y AND the existing groupFrames map. Reads are unrestricted; writes go through canvas_layout.js.
• Pick members. Identify which nodes belong in the proposed frame by looking at their ids, labels, prompts, and subtypes. Keep only ids that actually exist in nodes.
• Plan positions. Preserve existing positions when they already read well. Otherwise move the selected nodes into a compact layout for the chosen pattern. Use these default gaps:
• horizontal card gap: 40 px
• vertical row gap: 36 px
• frame padding: 24 px
• Evict existing frame members in the same layout JSON:
• If the old frame would still have ≥ 2 members after eviction: include it under groupFrames.upsert with memberIds minus the evictee.
• If the old frame would have < 2 members: include its id under groupFrames.delete.
• Compute frame bboxes from final member positions with 24px padding. Fallback sizes:
• note: 280 × 420 (width hardcoded; height = NOTE_CARD_FALLBACK_HEIGHT for first paint)
• image_result: 290 × 220 (16:9 default; if data.metadata.aspect_ratio is present, scale accordingly)
• video_result: 290 × 220 (same caveat; check data.aspect or data.metadata.aspect_ratio)
• audio_result: 240 × 64
• pending / pending_generation / pending_attachment: 260 × 200

If measured heights appear in canvas_positions.json, prefer them.

   minX = min(node.x for each member)
   minY = min(node.y for each member)
   maxX = max(node.x + node.w for each member)
   maxY = max(node.y + node.h for each member)
   x = minX - 24
   y = minY - 24
   width  = (maxX - minX) + 48
   height = (maxY - minY) + 48

• Decide title + hue. Default hue 200 if you have no signal.
• Apply one layout update with all node moves and frame changes:

   node "$PAI_REPO_ROOT/server/cli/canvas_layout.js" \
     --layout-json '{"positions":{"note_2":{"x":120,"y":80},"image_3":{"x":440,"y":80},"video_1":{"x":760,"y":80}},"groupFrames":{"upsert":{"frame_1716579123456":{"memberIds":["note_2","image_3","video_1"],"x":96,"y":56,"width":978,"height":468,"hue":200,"title":"Scene 1 — Causeway"}},"delete":[]}}'

• Extending an existing frame — same CLI/frameId, full new memberIds, recomputed bbox.
• Confirm to the user in one sentence. Example: *"Grouped the three Morris reference shots under their own frame."*

What not to do

• Don't propose groupings proactively when there's no clear semantic tie — wait until grouping earns the frame.
• Don't use grouping as a generic tidy operation when there is no semantic tie.
• Don't write canvas_positions.json directly. Use canvas_layout.js so positions and frames apply together.
• Don't call removed workflow group ops (addGroup, updateGroup, deleteGroup).
• Don't nest (put one frame's id inside another frame's memberIds).
• Don't assign a node to two frames. Include any eviction in the same layout update.