references/layout-contract.md
# Layout Contract
A generated deck uses a JSON root with `summary` and `slides`. The final tree is an audit contract, not a rendering hint.
```json
{
"summary": {
"layout_policy": {
"safe_margin": 0.5,
"content_bottom": 6.7,
"footer_top": 6.85,
"minimum_gap": 0.12
},
"accessibility": {
"language": "en-US",
"presentation_title": "Quarterly operating review"
}
},
"slides": [{
"id": "s01_overview",
"title": "Operating margin improves after the cost reset",
"accessibility": { "reading_order": ["title"] },
"layout_tree": {
"slide_size": { "width": 13.333, "height": 7.5 },
"root_group_id": "root",
"groups": { "root": { "id": "root", "role": "slide", "layout_mode": "absolute", "object_ids": ["title"], "group_ids": [], "bbox": { "x": 0, "y": 0, "width": 13.333, "height": 7.5 } } },
"objects": { "title": { "id": "title", "kind": "text", "role": "title", "classification": "content", "content": { "text": "Operating margin improves after the cost reset" }, "style": { "font_size": 30, "color": "#111827" }, "bbox": { "x": 0.75, "y": 0.55, "width": 10.8, "height": 0.65 }, "z_index": 2 } }
}
}]
}
```
## Repair order
1. Move or resize bboxes, change z-order, or split a dense slide.
2. Shorten copy or enlarge the available text bbox.
3. Change type size only as a last resort; content never drops below 9 pt.
4. Rebuild and compare actual object bounds with the contract.
SKILL.md
---
name: pptx-slide-specification
description: "Use when authoring or repairing a coordinate-explicit JSON specification for an editable PPTX deck."
---
# PPTX Slide Specification
Author final coordinates directly in `layout_tree`. No renderer may decide placement, shrink text, or infer layout after the audit.
## Required contract
- The root JSON contains `summary` and `slides`.
- Every slide has a stable `id`, a message-led `title`, an accessibility reading order, and a complete `layout_tree`.
- A layout tree declares slide size, root group, id-keyed groups and objects, final inch bboxes, styles, z-indexes, and classifications.
- Every meaningful object has `id`, `kind`, `role`, `classification`, `content`, `style`, `bbox`, and `z_index`.
- Production `summary` contains an explicit `layout_policy` (safe margin, content bottom, footer top, minimum gap) and accessibility metadata.
## Authoring rules
1. Use stable readable IDs, absolute groups, and positive inch dimensions.
2. Keep normal content inside the safe margin and above the footer rail. Only background `layout_design` objects may be full bleed.
3. Use native `text`, `shape`, `line`, `table`, and `image` objects. Recreate labels and values from any supporting visual as native objects.
4. Give meaningful images alt text. Record `source_ref` for sourced claims.
5. Keep content text at 9 pt or greater; shorten, resize, or split dense content before reducing type.
6. Use shared grids, consistent gaps, explicit color, explicit font size, and an intentional z-order.
## Build contract
A task-local builder starts from a blank slide layout and maps all bboxes with `Inches(...)`. Explicitly set wrapping, disabled auto-size, text insets, anchors, alignment, fonts, colors, line settings, image aspect ratio, and hidden-slide state. Reject zero or negative geometry before adding an object.
See `references/layout-contract.md` for the compact schema and repair guidance.