Impeccable design skill for Claude

Impeccable is a design skill for coding agents, published by GitHub user pbakaus under the Apache 2.0 license. Its README says it started from Anthropic's frontend-design skill and grew into a fuller toolkit: one skill, 24 commands, live iteration in the browser and 61 rule-based checks for common problems in AI-generated interfaces. Anthropic does not publish it. For the basics of skills, see how Claude Skills work.

What the skill does

Everything runs through one command, /impeccable:

• Setup: /impeccable init inspects the project, asks only about missing facts, and writes a PRODUCT.md with the audience, purpose, constraints and voice. Later commands read it.
• Review: critique for a UX review of hierarchy and clarity, audit for accessibility, performance and responsive checks.
• Adjust: bolder, quieter, distill, typeset, layout, colorize, animate, clarify for interface copy, and harden for errors, overflow and edge cases.
• Finish: polish for a final pass before shipping.
• Live: variant mode that iterates on elements in the browser.

The skill lists patterns to avoid, such as overused fonts like Inter, gray text on colored backgrounds, pure black, cards nested in cards and bounce easing. The 61 checks run from a command-line tool or browser extension with no model and no API key.

When to use it

• A design review of an existing app before a launch.
• A team that wants shared words for design feedback, like "make this quieter".
• Catching generic patterns automatically in pages an agent builds.

If you want something smaller, frontend-design is a single short brief, and Taste Skill focuses on landing pages. Our AI coding tools guide and coding prompts cover the rest of the build.

How to install it

From your project root:

npx impeccable install

The installer detects your agents (Claude Code, Codex, Cursor and others), asks whether to install for the project or globally, and on Claude Code also installs a project hook. Then run /impeccable init. Claude Code users can instead add the plugin marketplace and pick Impeccable from /plugin:

/plugin marketplace add pbakaus/impeccable

Example request

/impeccable critique [page or route, e.g. pricing]
Then run /impeccable audit on the same page and list the fixes in priority order before changing anything.

Limits

• The skill runs a separate engine, a compiled binary that is downloaded once on first run into ~/.impeccable/bin/ unless it ships next to the launcher. Review that step as you would any installed program.
• The installer adds hooks to your project on several agents. Codex and some others ask you to approve them.
• It is a large toolkit. For a one-off page, a short brief may be enough.