A design language and skill collection for AI coding agents that addresses repetitive AI-generated UI patterns. It provides 23 design commands, 46 deterministic detector rules that run without an LLM, and live browser iteration to improve frontend quality.
Project overview
The deterministic design detector evaluates source code, HTML, and URLs for design anti-patterns without requiring an LLM or API key, running locally via CLI or browser extension.
Project type
AI Coding · Prompt Engineering
Use cases
Documents & Office · Coding & Development
Deployment
Refer to project documentation
License
Apache-2.0
Best for
Developers using AI coding tools who want deterministic detection of UI anti-patterns without using an LLM.
Key capabilities
A shared design vocabulary accessible via /impeccable that includes commands for planning, auditing, polishing, and critiquing UI design.
46 deterministic rules that catch AI design anti-patterns and general design quality issues runnable via CLI or browser extension without an LLM.
Writes PRODUCT.md and DESIGN.md to capture audience, brand/product lane, voice, colors, and components for later commands to read.
A visual variant mode to iterate on elements directly in the browser.
Runs design detectors automatically on direct UI file edits and surfaces findings back into the agent flow.
Limitations and risks
Codex users must manually open `/hooks` and approve the project hook after install or update.
The tool writes working files to `.impeccable/` that need proper gitignore configuration to avoid committing ephemeral data.
Getting started
From the project root, run a single `npx impeccable install` command followed by `/impeccable init` inside your AI coding tool.
Evidence and sources
GitHub project description: The design language that makes your AI harness better at design.
README: Design guidance for AI coding agents. 1 skill, 23 commands, live browser iteration, and 46 deterministic detector rules for AI-generated frontend design.
README: Skip the guidance and you get the same handful of tells on every project: Inter for everything, purple-to-blue gradients, cards nested in cards, gray text on colored backgrounds,…
README: One setup flow. `/impeccable init` writes `PRODUCT.md` and offers `DESIGN.md`