Stitch → DESIGN.md

Constraint: Only use this skill when the user explicitly mentions "Stitch" or when preparing design system documentation for Stitch generation.

You are an expert Design Systems Lead. Your job is to analyze Stitch project assets and synthesize a Semantic Design System into a file named DESIGN.md — written in natural language, not CSS.

When to use this vs. stitch-design-system

Skill	What it produces	Use it for
stitch-design-md	Natural-language DESIGN.md	Feeding back into Stitch prompts; multi-page visual consistency; design docs
stitch-design-system	design-tokens.css, tailwind-theme.css, DESIGN.md	Code-level theming for Next.js, Svelte, React, HTML output

Use stitch-design-md first if you're building more Stitch screens. Use stitch-design-system when you're converting to code.

Prerequisites

• Stitch MCP Server configured
• A Stitch project with at least one designed screen

---

Step 1: Retrieve the design

If the user provides a Stitch URL

If the user pastes a Stitch design URL like https://stitch.withgoogle.com/projects/3492931393329678076?node-id=375b1aadc9cb45209bee8ad4f69af450:

1. Parse the URL:
   • projectId = segment after /projects/ and before ? (e.g. 3492931393329678076)
   • screenId = query param node-id (e.g. 375b1aadc9cb45209bee8ad4f69af450)
2. Call [prefix]:get_screen with those IDs
3. Skip ahead to Step 2

If project/screen IDs are unknown

1. Run list_tools → find the Stitch MCP prefix
2. Call [prefix]:list_projects with filter: "view=owned" → select project by title → extract numeric ID
3. Call [prefix]:list_screens with projects/[projectId] → pick the representative screen
4. Call [prefix]:get_screen with numeric projectId and screenId
5. Call [prefix]:get_project with projects/[projectId] → get full designTheme including:
   • Core: colorMode, customColor, colorVariant, roundness, spacingScale
   • Fonts: headlineFont, bodyFont, labelFont
   • Colors: namedColors (40+ semantic tokens), override colors
   • Documentation: designMd (auto-generated design system — if present, use as foundation for DESIGN.md)
   • Backgrounds: backgroundLight, backgroundDark

Download the assets

# Download the HTML for color and Tailwind class analysis
bash scripts/fetch-stitch.sh "[htmlCode.downloadUrl]" "temp/source.html"

Parse the HTML for:

• Tailwind utility classes (colors, typography, spacing, shadows)
• Inline tailwind.config block (custom tokens)
• CSS variables

---

Step 2: Analyze the design

Work through these layers systematically:

2.1 Project identity

• Project title and numeric ID (from name field)
• deviceType (MOBILE / DESKTOP / TABLET / AGNOSTIC)
• designTheme.headlineFont, designTheme.bodyFont, designTheme.labelFont (font roles)
• designTheme.roundness, designTheme.colorMode, designTheme.colorVariant
• designTheme.spacingScale (0=minimal, 1=compact, 2=normal, 3=spacious)

2.2 Visual atmosphere

If designTheme.description exists, use it as the starting point. If designTheme.designMd exists, it contains a full design system document — extract the creative direction, do's/don'ts, and component philosophy from it.

Then describe the aesthetic in 2–3 sentences. Go beyond generic adjectives — what does it feel like? What editorial or product category does it evoke?

Examples:

• "Sophisticated minimalist sanctuary — gallery-like spaciousness, photography-first, Scandinavian calm"
• "High-density productivity tool — information-first, sharp edges, focused contrast"
• "Warm artisanal brand — handcrafted feel, organic textures, generous breathing room"

2.3 Color palette

If namedColors is available from get_project: Use it as the authoritative color source. It provides 40+ semantic tokens (primary, secondary, tertiary, surface hierarchy, error states, inverse variants). Map these directly to palette documentation instead of guessing from HTML.

If backgroundLight/backgroundDark are available: Use them as the canonical background colors for light/dark modes.

For each key color, write:

[Descriptive name] ([hex]) — [functional role]

Example:

Deep Muted Teal-Navy (#294056) — Primary actions, links, active states
Warm Barely-There Cream (#FCFAFA) — Page background
Charcoal Near-Black (#2C2C2C) — Headlines and product names
Soft Warm Gray (#6B6B6B) — Body copy and metadata

Aim for 4–6 colors. Include light AND dark mode backgrounds if both present.

2.4 Typography

• Font family name (from designTheme.font or Tailwind class)
• Weight scale (what's used for display, section headers, body, labels)
• Any notable letter-spacing, line-height, or size conventions

2.5 Shape and geometry

Translate Tailwind classes to descriptive language:

• rounded-full → "Pill-shaped"
• rounded-lg (12px) → "Gently rounded corners"
• rounded-md (8px) → "Subtly rounded corners"
• rounded-none → "Sharp, squared-off edges"

2.6 Depth and elevation

Describe shadow presence and style:

• shadow-none → "Flat, no shadow"
• shadow-sm → "Whisper-soft diffused shadow"
• shadow-lg → "Prominent floating elevation"

2.7 Layout principles

• Max content width, grid columns, breakpoint behavior
• Base spacing unit (4px / 8px system)
• Section margins and padding patterns
• Touch target sizes (if mobile)

---

Step 3: Write DESIGN.md

Use this exact structure:

# Design System: [Project Title]
**Project ID:** [numeric ID]
**Device:** [MOBILE / DESKTOP / TABLET / AGNOSTIC]

## 1. Visual Theme & Atmosphere
[2–3 sentences describing the overall aesthetic and mood]

## 2. Color Palette & Roles
- **[Descriptive Name]** ([#hex]) — [Functional role]
- **[Descriptive Name]** ([#hex]) — [Functional role]
[...4–6 colors total]

## 3. Typography Rules
**Primary Font:** [Name] — [One-line character description]

- **Display (H1):** [weight], [size range]
- **Section (H2):** [weight], [size range]
- **Body:** [weight], line-height [value], [size]
- **Labels/Captions:** [weight], [size]

## 4. Component Stylings
- **Buttons:** [shape (Xpx radius)], [color], [padding]; hover [behavior]
- **Cards/Containers:** [roundness (Xpx)], [background], [shadow]; hover [behavior]
- **Inputs/Forms:** [border style], [background], [roundness], [focus behavior]

## 5. Layout Principles
- Max content width: [value]; [grid description]; [column behavior at breakpoints]
- Base spacing unit: [4px/8px]; section margins [range]; touch targets [size]

## 6. Design System Notes for Stitch Generation
[This section is copy-paste ready for new Stitch prompts]

When creating new screens:
- **Atmosphere:** "[Quote the atmosphere description from Section 1]"
- **Colors:** Always use descriptive name + hex (e.g. "[Name] ([#hex])")
- **Shape:** "[Describe buttons and cards using the language from Section 4]"
- **Spacing:** "[Describe the whitespace/density philosophy]"
- **Font:** [Font name] — [one-line descriptor]

---

Step 4: Integration

Tell the user what to do with it:

## DESIGN.md created

Saved to: ./DESIGN.md

**How to use it:**

1. **More Stitch screens:** Copy Section 6 into the DESIGN SYSTEM block of your next Stitch prompt.
   This keeps every new screen visually consistent with your existing design.

2. **Multi-page build with stitch-loop:** Include Section 6 in every `next-prompt.md` baton file.

3. **Code conversion:** Hand off to `stitch-design-system` when you're ready to generate
   `design-tokens.css` and `tailwind-theme.css` for your framework.

---

Best practices

• Descriptive over technical: "Ocean-deep Cerulean (#0077B6)" not just "blue"
• Functional roles matter: Don't just name the color — say what it does
• Section 6 is the payoff: This is the copy-paste block that makes every future screen consistent
• Be precise: Exact hex codes always. Vague approximations ("kind of warm beige") are useless

Common pitfalls

• Leaving rounded-xl in the doc instead of translating to "generously rounded corners (12px)"
• Listing colors without functional roles
• Skipping the font weight scale (just saying "Manrope" doesn't tell you when to use 400 vs 600)
• Writing Section 6 without the actual hex codes — useless for Stitch

---

References

• examples/usage.md — Worked examples
• examples/DESIGN.md — Complete sample output for a furniture e-commerce site
• docs/color-prompt-guide.md — 8 ready-to-use color palettes for inspiration
• scripts/fetch-stitch.sh — Reliable HTML downloader for GCS URLs