UI Preview — The Master Design Orchestrator

See it before you build it. This skill transforms vague user requests into precise, structured 'Construction Blueprints' for the Google Stitch AI generator, ensuring UI outputs are professional, consistent with project branding, and ergonomically sound.

When to Use

ALWAYS trigger when the task involves building, redesigning, or modifying UI:

• Creating new pages, screens, or layouts
• Building components (forms, cards, dashboards)
• Restyling or beautifying existing UIs
• Translating a wireframe or concept into high-fidelity UI

Trigger keywords: build UI, design page, create screen, landing page, dashboard layout, UI designer, use stitch, stitch me a ui, redesign, restyle

Architecture & Workflow (End-to-End)

This skill operates as a pipeline. Do not skip steps.

  ┌─────────────────────────────────────────────────────────┐
  │              cm-ui-preview Master Workflow              │
  ├─────────────────────────────────────────────────────────┤
  │                                                         │
  │  Step 1: PREFLIGHT & INTENT                             │
  │  ├── Detect task: New UI vs. Refine/Beautify            │
  │  └── Verify Stitch MCP tools availability               │
  │                                                         │
  │  Step 2: DESIGN SYSTEM EXTRACTION (The Source of Truth) │
  │  ├── Check: .stitch/DESIGN.md, css tokens, etc.         │
  │  └── Fallback: Trigger `cm-ux-master` to generate one   │
  │                                                         │
  │  Step 3: PROMPT ENHANCEMENT (The Build Blueprint)       │
  │  ├── Project Overview (What, who, style vibe)           │
  │  ├── Design System Specs (Colors, Typography, Layout)   │
  │  └── Page Structure (Core function + Specific areas)    │
  │                                                         │
  │  Step 4: STITCH EXECUTION (The Build Loop)              │
  │  ├── create_project()                                   │
  │  ├── generate_screen_from_text()                        │
  │  ├── Present link + AI insights to user                 │
  │  └── User Decision: Confirm / Edit / Skip               │
  │                                                         │
  │  Step 5: FINALIZATION & BATON PASS                      │
  │  ├── Save state to .stitch/next-prompt.md               │
  │  └── Hand off to cm-execution for actual coding         │
  │                                                         │
  └─────────────────────────────────────────────────────────┘

Step 1: Preflight & Intent Classification

1. Verify Stitch MCP: Check if create_project and generate_screen_from_text are available. If not, inform the user they are missing the Stitch tools but proceed with Prompt-Only generation (output the blueprint for them to use manually).
2. Classify Intent:
   • New Screen: Proceed with full generation.
   • Refine/Beautify (edit): Use edit_screens() on existing IDs instead of generate_screen_from_text().

Step 2: Design System Extraction (Source of Truth)

Before assembly, you MUST establish the design constraints.

Look for:

• .stitch/DESIGN.md (Primary source for Stitch)
• design-system/MASTER.md (From cm-ux-master)
• .cm/design-tokens.css or Tailwind configs

If no design system exists: Suggest running cm-ux-master or create a .stitch/DESIGN.md baseline. A baseline MUST contain:

• Platform (Web/Mobile)
• Primary/Secondary Colors (with hex codes)
• Typography (Font families)
• Component constraints (Rounded vs Sharp, Shadow levels)

Step 3: Prompt Enhancement Pipeline (CRITICAL)

DO NOT send vague prompts to Stitch (e.g., "Make a login page"). You must assemble an "Optimized Prompt Structure" — a detailed construction blueprint.

Structure your prompt exactly like this:

[Overall vibe, mood, and purpose of the page: e.g., "A modern fintech dashboard for B2B users. Professional, trustworthy, high data density, light mode."]

**DESIGN SYSTEM (REQUIRED):**
- Platform: Web Desktop-first
- Palette: Primary Blue (#0F62FE), Secondary Gray (#F4F4F4), Danger Red (#DA1E28)
- Typography: Inter for UI, Roboto Mono for numbers
- Styles: 4px border radius, subtle drop shadows on cards

**PAGE STRUCTURE & FUNCTION:**
### 1. Dashboard Home
**Core function**: Overview of recent transactions and account health.
- **Top Nav**: Brand logo, Global Search input, User Avatar dropdown.
- **Hero/Header**: Greeting "Welcome back, {User}", Total Balance callout (Large bold text).
- **Main Function Area**:
  - Left col: Line chart showing 30-day revenue.
  - Right col: Vertical list of "Recent Transactions" (Icon, Title, Date, Amount (Green/Red)).
- **Action Area**: Primary CTA "Send Money" (Blue fill, large), Secondary "Download Statement" (Outline).

Refine UI terminology: Replace "nice buttons" with "Primary CTA", replace "boxes" with "Cards". Apply relevant constraints from cm-ux-master (e.g., Miller's Law for chunking lists).

Step 4: Stitch Execution (The Build Loop)

1. Project Creation:

   mcp_StitchMCP_create_project({ title: "UI Preview — {Feature}" })
   

2. Screen Generation:

   mcp_StitchMCP_generate_screen_from_text({
     projectId: "<id>",
     prompt: "<Your Optimized Prompt Blueprint>",
     deviceType: "DESKTOP" // or MOBILE
   })
   

3. User Presentation: Show the output, provide the URL, and present the AI Insights (from the tool's outputComponents response).

   🎨 **UI Preview Generated!**
   
   - **Stitch Project ID:** `<id>`
   - **View & Edit:** [Open in Google Stitch](https://stitch.withgoogle.com/projects/<id>)
   - **AI Insights:** [Any suggestions or notes returned by Stitch]
   
   What's next?
   1. ✅ **Confirm** — I will write the code matching this design exactly.
   2. ✏️ **Edit** — Tell me what to change, I'll update the preview.
   3. ⏭️ **Skip** — Proceed straight to coding.
   

Step 5: Finalization & Baton Pass

• If Confirm: Proceed to code implementation. You MUST follow the visual layout, spacing, and colors shown in the Stitch preview.
• If Edit: Call mcp_StitchMCP_edit_screens() with the specific element changes.
• Baton Update (Optional but Recommended): Maintain a .stitch/next-prompt.md to feed into the next agent task or session for continuity.

Anti-Patterns (Strict Prohibitions)

• ⛔ NO VAGUE PROMPTS: Never pass user input straight to Stitch without the Step 3 Enhancement Pipeline.
• ⛔ NO FAKE SUCCESS: If the MCP tool fails or isn't connected, do not hallucinate a success message or URL.
• ⛔ NO CODING (Yet): This phase is purely for DESIGN PREVIEW. Do not write React/Vue code until the user clicks "Confirm" or "Skip".
• ⛔ NO APP SCAFFOLDING: Do not initialize project codebases in this workflow.

Future: Pencil.dev Support

Pencil MCP tools are available and will be integrated as an alternative execution engine in future updates (batch_design, get_editor_state).