Windsurf rules

1---
2name: extract-design
3model: sonnet
4description: "Extract a Google DESIGN.md file from an HTML prototype (claude.ai/design or any styled page) using Puppeteer, producing machine-readable tokens and AI-generated prose. Use when the user has an HTML prototype and wants a DESIGN.md to anchor their project's visual identity, or when seed-conventions has just scaffolded a new project."
5---
6 
7# Extract DESIGN.md from HTML
8 
9> **HARD GATE** — Do NOT write DESIGN.md without Puppeteer dual-pass extraction. Tokens from static HTML (Cheerio, regex, string scanning) are invalid — they miss cascade, custom properties, and Tailwind resolution.
10>
11> **HARD GATE** — Do NOT claim certainty where evidence is thin. Low-confidence color roles, component classifications, and prose assertions MUST be flagged with `<!-- AGENT NOTE: uncertain — validate during grill-me. Evidence: [what was observed] -->`.
12>
13> **HARD GATE** — Do NOT ship DESIGN.md without running `npx @google/design.md lint`. Unvalidated output is unverified output. If lint is unavailable (offline), flag prominently in terminal and in DESIGN.md prose.
14 
15## Quick Start
16 
17```bash
18# First run — extract from HTML prototype
19node extract-design/scripts/extract.js --source ./prototype.html
20 
21# From a published URL
22node extract-design/scripts/extract.js --source https://my-prototype.example.com
23 
24# With a custom name
25node extract-design/scripts/extract.js --source ./proto.html --name &quot;My Design System&quot;
26 
27# Update — re-extract from new HTML, diff against existing
28node extract-design/scripts/extract.js --source ./proto-v2.html
29 
30# Lint-only — validate existing DESIGN.md without re-extraction
31node extract-design/scripts/extract.js --lint-only
32```
33 
34## Flow
35 
361. **Launch Puppeteer** — dual-pass (light + dark) with retry + timeout. CI flags: `--headless=new --no-sandbox --disable-gpu --disable-dbus --use-gl=angle --use-angle=swiftshader`.
372. **Collect styles** — `page.evaluate()` collects computed styles from every element. Returns raw JSON to Node.js. Browser = sensor; Node = brain.
383. **Classify tokens** — modular pipeline: colors (Material 3 roles), typography (scale detection), spacing (tolerance GCD), rounded (clustering), components (visual signature + pseudo-state variants).
394. **Generate prose** — AI heuristics produce all 8 DESIGN.md sections. Overview and Do's/Don'ts flagged with agent notes.
405. **Write + validate** — serialize to `specs/tech-architecture/DESIGN_LATEST.md`, run `npx @google/design.md lint`, report to terminal.
416. **Handoff** — writes `handoff.next_skill: grill-me` to `specs/state.yaml` with uncertain decisions context.
42 
43## Inputs
44 
45| Parameter | Required | Description |
46|-----------|----------|-------------|
47| `--source <file\|url>` | First run: yes. Update: optional | HTML prototype path or URL |
48| `--name <string>` | No | Design system name (defaults to `<title>` or directory name) |
49| `--lint-only` | No | Validate existing DESIGN.md without re-extraction |
50 
51## Output
52 
53- `specs/tech-architecture/DESIGN_LATEST.md` — replaces `DESIGN_PLAN_LATEST.md` as the canonical design artifact
54- Terminal summary: token counts, component count, lint result, uncertain decisions
55- Structured JSON log to stderr: extraction events, timing, counts
56- `specs/state.yaml` → `handoff.next_skill: grill-me` with context
57 
58## Error Tiers
59 
60| Tier | Condition | Response |
61|------|-----------|----------|
62| Fatal | No Chrome, page load timeout after retries | Exit non-zero, suggest fixes |
63| Degraded | Zero colors, zero typography, SPA shell | Write DESIGN.md with degradation warning |
64| Warned | Lint errors, uncertain decisions | Write DESIGN.md, flag in terminal, hand off to grill-me |
65 
66## Dependencies
67 
68- **Puppeteer** (Chrome binary) — wrapped behind `BrowserExtractor` interface for testability
69- **`@google/design.md`** (soft, via `npx`) — wrapped behind `DesignValidator` interface. Warns and skips if offline.
70 
71## verify
72 
73```bash
74node extract-design/tests/test-extraction.js
75```
76 
77See [REFERENCE.md](REFERENCE.md) for extraction algorithms and heuristics.
78 
79---
80 
81# Extract Design — Reference
82 
83## Extraction Algorithms
84 
85### Color Classification
861. Collect unique computed `background-color`, `color`, `border-color` from every DOM element.
872. Count frequency and context (text vs. bg vs. border vs. button).
883. Classify using Material 3 roles: surface = largest-area bg, on-surface = most-used text, tertiary = highest-saturation on CTAs, error = reddish.
894. Surface container levels: luminance-ordered. Hard-cap at 3 unless data supports 5.
905. Low-confidence → `<!-- AGENT NOTE -->` in Colors prose.
91 
92### Typography Classification
931. Collect unique (fontFamily, fontSize, fontWeight, lineHeight, letterSpacing) tuples.
942. Cluster by fontSize (±2px) → type scale.
953. Detect heading hierarchy from HTML tag + computed size.
964. Name levels: display-lg, headline-lg/md/sm, title-lg, body-lg/md/sm, label-lg/md/sm.
975. Parse `<link>` and `@font-face`; warn if computed font differs from declared.
98 
99### Spacing Classification
1001. Collect unique padding, margin, gap values. Filter: ignore values < 3 occurrences.
1012. Compute tolerance-based GCD (0.5px tolerance).
1023. Declare base unit. Detect half-step if gcd/2 values present ≥3 times.
1034. Map: unit×1 → sm, ×2 → md, ×4 → lg, ×8 → xl.
104 
105### Rounded Classification
1061. Collect unique border-radius values. Cluster (1px tolerance).
1072. Name: none (0), sm (smallest), md (median), lg (large), xl (largest), full (9999px).
108 
109### Component Detection
110- Button: w<300px, h<64px, bg+radius set, short text. cursor:pointer is bonus.
111- Card: bg+radius+padding set, larger area.
112- Input: `<input>` or `<textarea>` tag.
113- Pseudo-state variants: force :hover, :active, :focus for high-confidence components.
114 
115### Prose Generation
116Generates all 8 DESIGN.md sections. Overview and Do's/Don'ts flagged with `<!-- AGENT NOTE: Generated from visual analysis. Grill-me should validate. -->`.
117 
118## Material 3 Token Conventions
119Colors: primary, on-primary, secondary, tertiary, error, surface, on-surface, surface-container-*, outline, background, on-background.
120Typography: display-lg/md/sm, headline-lg/md/sm, title-lg/md/sm, body-lg/md/sm, label-lg/md/sm.
121Rounded: none, xs, sm, md, lg, xl, full.
122 
123## CI Compatibility
124Chrome flags: `--headless=new --no-sandbox --disable-gpu --disable-dbus --use-gl=angle --use-angle=swiftshader`
125 
126## Defensive Code
127Retry with backoff (3 attempts, 1s/2s/4s), Timeout (30s page load, 10s pseudo-state), Graceful degradation (Tier 2 on empty extraction).
128 
129## Known Risks
130- DESIGN.md spec is alpha. Skill pins to current spec.
131- Puppeteer is heavy (~300MB Chrome). Document requirement clearly.
132- Prose quality depends on AI heuristics. grill-me is the validation gate.
133