Extract design

Brand Extraction

Document an existing brand's visual language as a reusable, machine-readable design system. Output is faithful, audited, and explicitly flags what was observed vs. inferred.

When to use this skill

• "Extract the design system from [URL]"
• "Document the brand of [site / screenshot]"
• "Reverse-engineer the visual language of [X]"
• "Build a style guide from this site"
• "Capture the design tokens from [Figma/URL/image]"

When NOT to use this skill

• Generating a new brand from scratch. This skill only documents existing brands.
• Single-component reference. If the user just wants one button styled like X, build the button — don't run a full extraction.
• Code refactor / theme migration. This skill produces documentation, not codemod output.

Non-negotiables

These are the rules. Violations make the deliverable worthless.

1. Component anatomy must be exhaustive. Every sub-element of every component is documented by name, with its tokens, behaviors, and relationships to other sub-elements. "Card: padded container with shadow" is a failure. See references/component-anatomy.md for the required level of detail.

2. Motion is a first-class extraction layer. Library detection (GSAP, Framer Motion, Lottie, Three.js, vanilla canvas), choreography (timelines, staggers, scroll-driven), and reduced-motion fallbacks are all required. Tokens alone (durations, easings) are insufficient. See references/motion-extraction.md.

3. Custom implementations get full anatomy. Canvas particle fields, Three.js scenes, hand-animated SVG, shaders — these aren't "components with custom interactivity," they're separate rendering pipelines and must be documented with the same depth as components, including driving variables, render-loop pseudocode, and a reconstruction strategy. See references/custom-implementation.md.

4. Confidence is flagged on every token. confirmed (read directly from CSS/source), inferred-likely (visual inference with strong evidence), or inferred (visual approximation). No silent guessing.

5. The preview must itself feel like the brand. A spec sheet rendered in Inter on white is a failure when documenting a brand whose voice is, say, brutalist editorial. The preview is a proof the system works on itself. See references/preview-principles.md.

6. Three-file deliverable, always. tokens.json + preview.html + README.md. Even if the user only asks for one, produce all three — they reference each other.

7. Self-audit before delivery. Diff the reconstructed components against the original. If a reconstructed button looks meaningfully different from the real one, the extraction is wrong.

Workflow

Run all phases in order. Don't skip Phase 0 — it prevents permission interruptions for the rest of the run.

Phase 0 — Pre-flight. Write the project's .claude/settings.json allowlist so every subsequent Bash call in the session is auto-approved. Create the output directory. See references/workflow.md §0.

Phase 1 — Reconnaissance. Fetch the source. Get content + visual references. Detect motion libraries and custom rendering (GSAP, Framer Motion, Lottie, Three.js, canvas). Structural scoring auto-detects atoms and compound components (works on Tailwind, CSS-in-JS hashed names, and custom BEM — no class-name dependency). See references/workflow.md §1 and references/motion-extraction.md Phase 1 addendum.

Phase 2 — Token extraction. Pull primitives: color, type, space, radius, shadow, motion. Rank by frequency. See references/workflow.md §2.

Phase 3 — Atom identification. Map the smallest reusable units. Reads manifest.atoms as the starting inventory — each entry has multi-state screenshots (default/hover/focus) captured automatically. See references/atom-checklist.md for the canonical set.

Phase 4 — Component anatomy. Decompose every component into named sub-elements with full specs. This is a non-negotiable phase. Reads manifest.componentStates as the starting inventory — each entry has state screenshots (default/hover/child-hover/active/focus) for direct token diffing. See references/component-anatomy.md.

Phase 4.5 — Motion + custom implementation extraction. Document every motion pattern (CSS, JS, scroll-driven, Lottie) and every custom rendering (canvas, WebGL, manual SVG). Also non-negotiable. See references/motion-extraction.md and references/custom-implementation.md.

Phase 5 — Brand identity synthesis. Voice, principles, photography treatment, motion character. The qualitative layer.

Phase 6 — One-pager preview. Build preview.html using only the extracted tokens. The preview itself must be styled in the source brand's aesthetic, and should reconstruct motion/custom impls where feasible (or show labeled static frames). Write the file section-by-section using the Edit-append pattern — never output the full HTML in context. See references/preview-principles.md and references/workflow.md §6.

Phase 7 — Self-audit. Compare reconstruction to source. Flag gaps. List items requiring manual verification — including motion library confidence and custom impl reconstruction trade-offs.

Full details in references/workflow.md.

Outputs

Every extraction run writes to a dedicated directory in the current project:

.extract-design/<brand-slug>/
├── capture-manifest.json   ← Playwright capture index + confirmed DOM data (Phase 1)
├── screenshots/            ← Playwright screenshots (viewports, scroll, hover)
├── tokens.json             ← machine-readable design tokens with confidence flags
├── preview.html            ← self-contained one-pager, styled in source's aesthetic
└── README.md               ← brand identity write-up + extraction methodology

<brand-slug> is derived from the target URL hostname (stripe.com → stripe). The user can override it with an explicit name.

Use the templates in templates/ as starting scaffolds for tokens.json, preview.html, and README.md. They have the structure pre-wired and the token CSS variables already plumbed through.

Reading order

When this skill is loaded, read in this order:

1. This file (you're here)
2. references/workflow.md — the full 7-phase playbook
3. references/playwright-screenshots.md — capture protocol, output directory, manifest structure
4. references/component-anatomy.md — read carefully, this is a non-negotiable
5. references/motion-extraction.md — read carefully, this is a non-negotiable
6. references/custom-implementation.md — read carefully, this is a non-negotiable for any site using canvas/WebGL/manual SVG
7. references/atom-checklist.md — the canonical atom set
8. references/preview-principles.md — what makes a good preview
9. references/token-schema.md — exact JSON schema with confidence flags