Paul BakausandClaude Opus 4.6
e1032b7285
A new icon-tile-stack detection (the canonical AI feature-card with a small rounded-square icon container above a heading), backed by a two-column TDD fixture, plus a single-source-of-truth design that ties the engine to the impeccable skill so they can no longer drift silently. Detection - New icon-tile-stack rule (slop): heading's previousElementSibling is a 32–128px rounded-square element with a non-transparent background or border, contains an svg/icon-i child, and sits above (not next to) the heading. Excludes round avatars, wide thumbnails, side-by-side layouts, tiny icons, and hero images. - Two-column fixture convention: a single icon-tile-stack.html with a flag column (4 cases) and pass column (6 cases), with snippet-text matching used by the fixture test. Single source of truth - Each ANTIPATTERNS entry can now declare skillSection + skillGuideline. 18 of 25 rules carry these fields; the build's new validateAntipatternRules() in scripts/build.js fails if any declared skillGuideline isn't found verbatim in the right SKILL.md section. - scripts/build-extension.js now includes the description field in extension/detector/antipatterns.json (it was previously dropped). - The existing count validator was promoted from warn to error so command count drift fails the build the same way detection drift does. Impeccable skill DON'Ts - Added 4 new top-level DON'Ts that target real default AI behavior: single-font, flat-type-hierarchy, all-caps-body, line-length. - Cut 7 new DON'Ts I had drafted (tight-leading, tiny-text, wide-tracking, justified-text, low-contrast, cramped-padding, skipped-heading) because they teach things every model already knows from CSS/a11y basics. The detector still catches all of them. Stale count cleanup - 22 commands → 21 across 17 references in HTML, README, NOTICE, AGENTS, plugin.json, marketplace.json (left over from the validate skill removal). - Dropped the hand-coded "212 design guidelines" marketing copy on the homepage, which never mapped to any real count. Sub-agent - New private .claude/agents/anti-patterns.md captures the full TDD recipe, schema, plug-in points, jsdom constraints, and pre-commit checklist so future sessions can add rules end-to-end without re-investigating the wiring. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Impeccable
The vocabulary you didn't know you needed. 1 skill, 21 commands, and curated anti-patterns for impeccable frontend design.
Quick start: Visit impeccable.style to download ready-to-use bundles.
Why Impeccable?
Anthropic created frontend-design, a skill that guides Claude toward better UI design. Impeccable builds on that foundation with deeper expertise and more control.
Every LLM learned from the same generic templates. Without guidance, you get the same predictable mistakes: Inter font, purple gradients, cards nested in cards, gray text on colored backgrounds.
Impeccable fights that bias with:
- An expanded skill with 7 domain-specific reference files (view source)
- 21 steering commands to audit, review, polish, distill, animate, and more
- Curated anti-patterns that explicitly tell the AI what NOT to do
What's Included
The Skill: impeccable
A comprehensive design skill with 7 domain-specific references (view skill):
| Reference | Covers |
|---|---|
| typography | Type systems, font pairing, modular scales, OpenType |
| color-and-contrast | OKLCH, tinted neutrals, dark mode, accessibility |
| spatial-design | Spacing systems, grids, visual hierarchy |
| motion-design | Easing curves, staggering, reduced motion |
| interaction-design | Forms, focus states, loading patterns |
| responsive-design | Mobile-first, fluid design, container queries |
| ux-writing | Button labels, error messages, empty states |
21 Commands
| Command | What it does |
|---|---|
/impeccable teach |
One-time setup: gather design context, save to config |
/audit |
Run technical quality checks (a11y, performance, responsive) |
/critique |
UX design review: hierarchy, clarity, emotional resonance |
/normalize |
Align with design system standards |
/polish |
Final pass before shipping |
/distill |
Strip to essence |
/clarify |
Improve unclear UX copy |
/optimize |
Performance improvements |
/harden |
Error handling, i18n, edge cases |
/animate |
Add purposeful motion |
/colorize |
Introduce strategic color |
/bolder |
Amplify boring designs |
/quieter |
Tone down overly bold designs |
/delight |
Add moments of joy |
/extract |
Pull into reusable components |
/adapt |
Adapt for different devices |
/onboard |
Design onboarding flows |
/typeset |
Fix font choices, hierarchy, sizing |
/arrange |
Fix layout, spacing, visual rhythm |
/overdrive |
Add technically extraordinary effects |
Usage Examples
/audit - Run quality checks, get a report (no edits)
/audit blog # Audit blog hub + post pages
/audit dashboard # Check dashboard components
/audit checkout flow # Focus on checkout UX
When to use: Before making changes, to understand what needs fixing.
/normalize - Align with design system
/normalize blog # Apply design tokens, fix spacing
/normalize buttons # Standardize button styles
When to use: After audit, to fix inconsistencies.
/critique - UX design review
/critique landing page # Review landing page UX
/critique onboarding # Check onboarding flow
When to use: When you want design feedback, not technical fixes.
/polish - Final pass before shipping
/polish feature modal # Clean up modal before release
/polish settings page # Final review of settings UI
When to use: Last step before deploying to production.
Combining commands:
/audit /normalize /polish blog # Full workflow: audit → fix → polish
/critique /harden checkout # UX review + add error handling
Anti-Patterns
The skill includes explicit guidance on what to avoid:
- Don't use overused fonts (Arial, Inter, system defaults)
- Don't use gray text on colored backgrounds
- Don't use pure black/gray (always tint)
- Don't wrap everything in cards or nest cards inside cards
- Don't use bounce/elastic easing (feels dated)
See It In Action
Visit impeccable.style to see before/after case studies of real projects transformed with Impeccable commands.
Installation
Option 1: Download from Website (Recommended)
Visit impeccable.style, download the ZIP for your tool, and extract to your project.
Option 2: Copy from Repository
Cursor:
cp -r dist/cursor/.cursor your-project/
Note: Cursor skills require setup:
- Switch to Nightly channel in Cursor Settings → Beta
- Enable Agent Skills in Cursor Settings → Rules
Claude Code:
# Project-specific
cp -r dist/claude-code/.claude your-project/
# Or global (applies to all projects)
cp -r dist/claude-code/.claude/* ~/.claude/
OpenCode:
cp -r dist/opencode/.opencode your-project/
Pi:
cp -r dist/pi/.pi your-project/
Gemini CLI:
cp -r dist/gemini/.gemini your-project/
Note: Gemini CLI skills require setup:
- Install preview version:
npm i -g @google/gemini-cli@preview- Run
/settingsand enable "Skills"- Run
/skills listto verify installation
Codex CLI:
cp -r dist/codex/.codex/* ~/.codex/
Trae:
# Trae China (domestic version)
cp -r dist/trae/.trae-cn/skills/* ~/.trae-cn/skills/
# Trae International
cp -r dist/trae/.trae/skills/* ~/.trae/skills/
Note: Trae has two versions with different config directories:
- Trae China:
~/.trae-cn/skills/- Trae International:
~/.trae/skills/After copying, restart Trae IDE to activate the skills.
Rovo Dev:
# Project-specific
cp -r dist/rovo-dev/.rovodev your-project/
# Or global (applies to all projects)
cp -r dist/rovo-dev/.rovodev/skills/* ~/.rovodev/skills/
Usage
Once installed, use commands in your AI harness:
/audit # Find issues
/normalize # Fix inconsistencies
/polish # Final cleanup
/distill # Remove complexity
Most commands accept an optional argument to focus on a specific area:
/audit header
/polish checkout-form
Note: Codex CLI uses a different syntax: /prompts:audit, /prompts:polish, etc.
CLI
Impeccable includes a standalone CLI for detecting anti-patterns without an AI harness:
npx impeccable detect src/ # scan a directory
npx impeccable detect index.html # scan an HTML file
npx impeccable detect https://example.com # scan a URL (Puppeteer)
npx impeccable detect --fast --json . # regex-only, JSON output
The detector catches 24 issues across AI slop (side-tab borders, purple gradients, bounce easing, dark glows) and general design quality (line length, cramped padding, small touch targets, skipped headings, and more).
Supported Tools
Contributing
See DEVELOP.md for contributor guidelines and build instructions.
License
Apache 2.0. See LICENSE.
The impeccable skill builds on Anthropic's original frontend-design skill. See NOTICE.md for attribution.
Created by Paul Bakaus