Impeccable — 23 Design Commands + 46 Deterministic Rules for AI Frontends
A design-guidance system for AI coding agents by jQuery UI creator Paul Bakaus (46.7k stars): one skill, 23 commands (polish/critique/bolder/distill…), live browser iteration, plus 46 deterministic detector rules that run with no LLM — calling out the exact AI tells: Inter everywhere, purple-blue gradients, cards nested in cards.
Impeccable's diagnosis of "AI slop" is blunt: every model trained on the same SaaS templates, so unguided output shares the same tells — Inter for everything, purple-to-blue gradients, cards nested in cards, gray text on colored backgrounds, the rounded icon tile above every heading. Starting from Anthropic's official frontend-design skill, it builds a full engineering-grade system.
Three layers: /impeccable init writes PRODUCT.md and DESIGN.md (audience, brand lane, anti-references, color, type) that every later command reads; 23 commands form a shared design vocabulary with your AI — critique (UX review), audit (a11y/performance/responsive), polish, bolder/quieter (a volume dial pair), distill, harden (error states/i18n/text overflow), animate, delight, and live (real-time variant iteration in the browser); and hardest-core, 46 deterministic detector rules that the CLI and browser extension run with no LLM and no API key.
Install coverage is huge: one npx command targets Claude Code, Cursor, Gemini CLI, Codex, Copilot, Trae (incl. the China build) and a dozen more, and frequent commands can be pinned as standalone shortcuts.
Same race as taste-skill, different lane: taste-skill injects taste and style variants; Impeccable runs on process commands plus reviewable hard rules. They coexist fine — one keeps the starting point from being ugly, the other keeps shipping from being sloppy.
FAQ
What is Impeccable?
A design-guidance system for AI coding agents: one skill, 23 commands, live browser iteration, plus 46 deterministic detector rules that need no LLM — by jQuery UI creator Paul Bakaus.
How do I install it?
Recommended: npx impeccable install (auto-detects Claude Code/Cursor/Codex setups). On Claude Code you can also /plugin marketplace add pbakaus/impeccable, or download a ZIP from impeccable.style.
What's special about the 46 deterministic rules?
The CLI and browser extension run them with no LLM and no API key — reviewable, reproducible checks that catch the AI tells: Inter everywhere, purple-blue gradients, cards nested in cards.
Which command do I start with?
/impeccable init — it asks whether your surface is brand or product, writes PRODUCT.md and DESIGN.md, and every later command reads that context.
Which AI tools does it support?
Claude Code, Cursor, Gemini CLI, Codex CLI, GitHub Copilot, OpenCode, Trae (incl. the China build), Rovo Dev, Qoder, and more.