Impeccable skill: what it does and how to install it

Source: pbakaus/impeccable · Maintainer: community: Paul Bakaus · License: Apache 2.0 · Checked: 23 October 2026

What is the Impeccable skill?

Impeccable is a design skill that gives your coding agent one /impeccable command with 24 sub-commands for planning, critiquing, auditing and refining a frontend, plus a detector for common AI-generated design tells. It is for developers who build UI with an agent and want a shared vocabulary ("polish the checkout", "make the hero quieter") and a quality floor the agent checks against.

The README says Anthropic's frontend-design skill "was the first widely-used design skill for Claude. Impeccable started from there." The skill's description reads: "Use when the user wants to design, redesign, shape, critique, audit, polish, simplify, harden, animate, or otherwise improve a frontend interface: websites, landing pages, dashboards, product UI, components, forms, settings, onboarding, empty states, and native iOS or Android screens. Handles UX review, hierarchy, layout, typography, color, motion, UX copy, accessibility, responsive behavior, edge cases, and capturing or documenting design systems (DESIGN.md, tokens). Also for making bland UI bolder, loud UI quieter, or ambitious visual effects. Not for backend-only or non-UI tasks."

As of 23 October 2026, its skills.sh page listed about 356,500 installs.

What does it do?

The SKILL.md casts the agent as "an award-winning design director" and sets three principles: finish the job, scale ambition to the surface, and verify by looking at the rendered result. Then it works through a few layers:

• Project context. Once per session the agent runs the bundled launcher with context, which loads PRODUCT.md (audience, purpose, voice), DESIGN.md (the visual system) and a brief for the page being worked on. /impeccable init writes PRODUCT.md the first time.
• Modes. Each surface gets a mode that defines success: Persuade (landing and pricing pages), Operate (app UI, dashboards, settings), Read (docs and articles) or Experience (portfolios and galleries). Persuade and Experience get bold, committed work; Operate and Read get precision and restraint.
• A quality floor. Before any UI edit, the agent reads reference/craft-floor.md, which holds "the quality floor, the absolute bans, and the reflexes no detector catches."
• Commands. Each sub-command has its own reference file. Typing /impeccable alone shows a menu and never auto-runs anything.

The 24 commands, grouped as the SKILL.md groups them:

There are also housekeeping commands: /impeccable pin audit creates a standalone /audit shortcut, /impeccable hooks manages the design hook, and /impeccable doctor reports drift between your project files and what the current version expects.

What's in the folder:

• SKILL.md: principles, setup, modes and the command table.
• reference/: 41 Markdown files, one per command plus modes, iOS and Android guidance, and the craft floor.
• scripts/: the impeccable launcher (and impeccable.cmd for Windows), a VERSION file, command metadata, a font index, and JavaScript for live browser mode, including a bundled screenshot library (modern-screenshot.umd.js).

The Claude Code plugin around the skill adds four helper agents and a hooks file.

What runs when you use it?

Impeccable is not just Markdown, so it is worth knowing what executes.

• The launcher. scripts/impeccable is a shell script that runs the Impeccable engine, a self-contained binary. It looks for the engine in this order: the IMPECCABLE_BIN variable, a bin/<os>-<arch>/ folder next to the launcher, ~/.impeccable/bin/ (after a quick handshake check), a version-pinned cache, then impeccable on your PATH.
• The download. If none is found, the launcher downloads the pinned version from the project's GitHub releases, checks it against a .sha256 file, and refuses to run it if the checksum is missing or wrong. When checked, the plugin's skill folder in the repo had no bin/ folder, so a plugin install fetches the engine on first run.
• Hooks. The plugin's hooks file runs impeccable hook when a session starts, after every Edit or Write, and when Claude stops. The README warns that in Claude Code these hooks "run independently of model-tool approval," so the first edit can download the engine even if you denied the agent's launcher command. It suggests reviewing hooks before unattended runs; see Claude Code hooks.
• Telemetry. When a new design starts, the skill asks an API at impeccable.style to deal a hand of visual worlds. Unless you opt out, an anonymous record of what was shown and chosen is kept. The README says your project name, files, code and PRODUCT.md are never sent. Opt out with npx impeccable telemetry off, DO_NOT_TRACK=1 or IMPECCABLE_NO_TELEMETRY=1.
• Live mode. Applying copy edits in live mode runs your package.json script impeccable:manual-edit-validate, if present, in a shell. The README says to use live mode only in projects you trust, and that using it on a deployed production site is not supported.

How do you install the Impeccable skill?

The installer (recommended by the README). From your project root:

npx impeccable install

It shows the coding tools it detected, lets you adjust the list, and asks whether to install into the project or globally. Use --providers=claude,codex,cursor and --scope=project or --scope=global to skip the questions. For Claude Code, Cursor, Codex, GitHub Copilot and Grok Build it also offers the design hook. Refresh later with npx impeccable update, then run /impeccable init in your agent. Node is needed only for npx itself.

Claude Code plugin. Add the marketplace, then open /plugin and install Impeccable from the list, as the README describes (see Claude Code's plugin docs):

/plugin marketplace add pbakaus/impeccable

The skills CLI. skills.sh lists this command for the skills CLI. It copies the skill folder but not the hook, which the installer and plugin set up:

npx skills add https://github.com/pbakaus/impeccable --skill impeccable

For Claude Code, a project install puts the skill in .claude/skills/impeccable/; global copies go under ~/.claude/. In Codex, open /skills or type $impeccable, and approve the project hook in /hooks after installing. Codex and Cursor read the same SKILL.md format; see Codex skills and Cursor skills. The README also covers a Git submodule setup, a ZIP download from impeccable.style, and copying from the repo.

claude.ai. The README doesn't document claude.ai. The frontmatter uses version, user-invocable and argument-hint, keys that Anthropic's skills docs say claude.ai uploads reject, and the skill expects to run a local binary. It is built for coding agents.

How do you use it?

Start every project with /impeccable init. After that, run a command with an optional target, or describe what you want after /impeccable.

Example prompts (suggestions, not quotes from the repo):

• /impeccable critique the pricing page
• /impeccable audit src/app/dashboard
• /impeccable polish the checkout form
• /impeccable quieter the hero section
• /impeccable shape a team settings screen with roles and invites

You can also run the detector without an agent. npx impeccable detect src/ scans a folder, --json gives CI output, and a URL scan uses an installed Chrome, Chromium or Edge.

Tips and limits

• The brief wins. The SKILL.md says to honor pinned fonts, palettes and eras even when they clash with its warnings. Tell it your constraints up front.
• Commit the right files. Impeccable writes working files to .impeccable/. The README gives a .gitignore block for screenshots and session state, and says to keep config.json, design.json, surfaces/*.md and critique/*.md tracked.
• A clean scan is not proof. The README calls a clean detector run "evidence, not proof of visual or accessibility quality." Still look at the result at real viewport sizes.
• Security audit. As of 23 October 2026, skills.sh showed Pass from Gen Agent Trust Hub and Snyk, and Warn from Socket. Socket's 20 October 2026 audit lists one low-severity anomaly in scripts/modern-screenshot.umd.js, noting "No definitive malware indicators" and that the risk comes from what the library is able to do (fetching remote resources while rendering). Review the scripts and hooks before installing.
• License. Apache 2.0. The repo's NOTICE file says the iOS and Android reference files are distilled from ehmo's platform-design-skills, used under its MIT license.

Save it in your Kipt library

In Kipt, open Skills and paste the skill's GitHub folder link into the import box. Kipt reads the SKILL.md and its files; for a repo with many skills it shows a list to pick from. You can also drop the folder or a .zip. Your skills live in your own private GitHub repo and install into Claude Code or Codex with one command:

npx skills add https://github.com/<you>/<repo>.git --all -g

Kipt is not affiliated with Paul Bakaus or the Impeccable project.

Similar skills

• Frontend design skill: Anthropic's design guidance that Impeccable started from, as one SKILL.md with no scripts.
• Design taste frontend skill: another skill for steering agents away from generic UI.
• UI UX Pro Max skill: a searchable local database of styles, palettes and UX rules.
• Web design guidelines skill: Vercel's file:line audit against its interface rules.