pix

name	pix
description	Launches an autonomous, pixel-perfect UI implementation loop using Figma MCP and Chrome.
allowed-tools	["Bash","Read","Glob","Grep","Edit","Write"]

/pix: The Pixel-Perfect Autonomous Loop

Note: This skill requires Figma MCP and Claude Chrome extension. Tool names may vary based on your MCP configuration (e.g., figma__get_screenshot or mcp__figma__get_screenshot). Run /mcp to see available tools.

Phase 0: Project Discovery

Before anything else, analyze the project to understand its stack:

1. Package Manager Detection

Check which lockfile exists: package-lock.json (npm), yarn.lock (yarn), pnpm-lock.yaml (pnpm), bun.lockb (bun). Use the corresponding command for all package operations.

2. Dev Server & Port Detection

• Read package.json scripts to find the dev command
• Check for port configuration in: vite.config.*, next.config.*, nuxt.config.*, webpack.config.*, .env*, or the dev script itself
• Common patterns: --port, -p, PORT=, server.port
• Default fallback order: 5173 (Vite), 3000 (Next/CRA), 8080 (Vue CLI)

3. Design System Detection

Scan package.json dependencies for styling approach:

• Tailwind: tailwindcss → config in tailwind.config.*
• CSS-in-JS: styled-components, @emotion/*, stitches
• Component Libraries: @chakra-ui/*, @mui/*, @mantine/*, antd, @radix-ui/*
• CSS Modules: check for *.module.css files
• Vanilla CSS/SCSS: check for global stylesheets

4. Icon Library Detection

Scan package.json and imports for icon libraries:

• lucide-react → Lucide
• @heroicons/react → Heroicons
• react-icons → React Icons (multi-library)
• @radix-ui/react-icons → Radix Icons
• @fortawesome/* → FontAwesome
• @phosphor-icons/react → Phosphor
• @tabler/icons-react → Tabler Icons
• If none found, ask user which to install or use inline SVGs

5. System Verification

1. MCP Check: Verify Figma MCP is connected and authenticated:
   • Call whoami to check authentication status
   • If not connected: alert user to configure Figma MCP
   • If not authenticated: guide user to authenticate via Figma OAuth
   • Display the authenticated user info to confirm correct account
2. Chrome Check: Ensure Claude Chrome extension is active and connected.
3. Dev Server: Using detected port, run lsof -i :<PORT> to check if server is already running. If running, leave it alone. If not running, start dev server in background using detected package manager and script.

Phase 1: Context Gathering

Chrome Setup

Open Chrome with localhost:<DETECTED_PORT>:

• Navigate to the page/route where the component will live
• This tab is used for visual comparison and interaction testing (hover, click, focus states)
• Zoom in on the component area for more detailed screenshots

User Input

Stop and Ask:

• "Paste the Figma link to the component you want to build"
• (Use 'Copy link to selection' in Figma)

Note: No need to open Figma in Chrome — Figma MCP handles screenshots via get_screenshot.

Phase 2: The Magic Prompt (Deep Execution)

Once the link is provided, you must execute this EXACT sequence. Do not skip details:

1. Hard Data Extraction (Figma MCP)

Use these Figma MCP tools in sequence:

• Structure: Use get_metadata to understand the component hierarchy and layer structure.
• Design Context: Use get_design_context to get the full design specification including layout, spacing, and styles.
• Tokens: Use get_variable_defs to extract hex codes, corner-radius, shadows, and typography tokens.
• Existing Components: Use get_code_connect_map to check if any Figma components already map to code components in the codebase. Reuse existing components instead of recreating them.
• Typography: Get numeric font-weight (e.g., 600 vs 700), line-height, and letter-spacing.
• Icon Colors: Extract icon stroke/fill colors separately from text colors. Check --stroke-0, fill, or style definitions. Never assume icons inherit text color.
• Container Layout Analysis: Before implementing, identify:
  • Which elements share a common background vs have distinct backgrounds
  • Where borders/dividers separate sections
  • Whether sections extend edge-to-edge within their parent or are visually inset

2. Exhaustive Property Verification

Rule: Before writing code for ANY element, call get_design_context and verify ALL applicable properties. Never assume inheritance or defaults. Extract each value explicitly.

Text: font-family, font-size, font-weight, line-height, letter-spacing, color, opacity, text-align, text-decoration, text-transform

Container/Block: width, height, min-width, max-width, padding (all 4 sides), margin, background-color, border-radius, border-width, border-color, border-style, box-shadow, opacity, overflow

Icon: size (width/height), fill, stroke, stroke-width, color (independent from parent text)

Button/Link: All text properties + all container properties + cursor, hover-state, active-state, disabled-state

Image: width, height, object-fit, border-radius, border, aspect-ratio

Spacing: gap, row-gap, column-gap, space-between elements

Layout Principle: Avoid hardcoded sizes (max-w-[140px], w-[200px], etc.). With correct font-size, line-height, padding, and parent container width, elements should naturally render correctly. Hardcoded dimensions are a symptom of incorrect upstream layout — fix the root cause instead.

Responsive Design: Keep responsiveness in mind as a big plus. Even if only one breakpoint is provided in Figma, consider how the component should adapt to different screen sizes. When possible, implement both desktop and mobile-friendly styles using the project's responsive approach (Tailwind breakpoints, CSS media queries, container queries).

Never use approximate Tailwind classes (like text-zinc-500) when exact hex values are available from MCP.

3. Design System Sync

NEVER hardcode values. Always sync to the project's design system:

• If Tailwind: Check tailwind.config.*. If a Figma value is missing, update the config. NEVER hardcode arbitrary hex values like text-[#f3f3f3] if they should be tokens.
• If CSS-in-JS: Add tokens to the theme object/file. NEVER use inline hex values.
• If Component Library: Map to existing theme tokens, extend theme if needed. NEVER bypass the theme.
• If CSS/SCSS: Add CSS custom properties to :root. NEVER scatter magic values.

4. Icons

Map Figma layer names to the project's detected icon library. Match the stroke-width and size (px) to the design exactly. If no icon library exists, ask user preference or use inline SVG from Figma.

5. Implementation & "Building Brick" QA

Implement the code using the project's existing patterns, then start the Comparison Loop:

1. Screenshot App: Use Chrome to capture the rendered component at localhost:<DETECTED_PORT>.
2. Screenshot Figma: Use get_screenshot to get the high-res reference from Figma.
3. The "Brick" Checklist: Compare the following with 1:1 scrutiny:
   • Titles: Is the font boldness and vertical alignment identical?
   • Icon Shapes: Does the icon look exactly like the Figma version? Check the stroke thickness.
   • Icon Colors: Are icon colors identical to or different from adjacent text?
   • Distances: Measure the gaps/margins. If Figma says 24px and the app looks like 20px, refactor.
   • Borders: Verify 1px vs 2px lines and the exact curve of border-radius.
   • Edge-to-Edge vs Inset: Does each section extend to its parent container's edges, or does it appear "floating" with visible gaps?
   • Background Continuity: Does the background of a section touch its parent's boundaries, or is there a gap revealing the parent's background?
   • Padding Ownership: Is the spacing between content and edges created by the parent container or the child? This affects whether backgrounds extend correctly.

Phase 3: Recursive Refinement

If you find ANY discrepancy (even 1px):

1. Explain what is wrong.
2. Fix the code.
3. Repeat Phase 2, Step 5 (Screenshot QA).

Success Condition: Only finished when side-by-side screenshots prove local app and Figma design are indistinguishable.

Phase 4: User Review

Once you're satisfied with the result, stop and ask:

• "Here's the final result. Are you happy with it?"
• "If something looks off, paste a Figma 'Link to Selection' for the specific area you'd like me to focus on."

If the user provides a new link, re-run Phase 2 scoped to that specific selection. This allows targeted refinement of individual building blocks without restarting the full component.

ULTRA-THINK MODE ENABLED: Take your time. Perfection over speed.

Examples

Good invocation:

/pix
> Paste Figma link: https://figma.com/design/abc123/MyApp?node-id=42-100

What Claude does:

1. Detects: Vite + Tailwind + Lucide icons
2. Extracts: colors, typography, spacing from Figma
3. Updates: tailwind.config.js with missing tokens
4. Implements: component with exact values
5. Screenshots: both app and Figma
6. Compares: finds 2px gap difference
7. Fixes: adjusts padding
8. Repeats: until pixel-perfect match

Bad patterns to avoid:

• ❌ text-[#f3f3f3] — hardcoded hex in Tailwind
• ❌ w-[247px] — magic width number
• ❌ Assuming icon color matches text
• ❌ Skipping screenshot comparison