@impeccable/detect

Deterministic UI anti-pattern detector. Catches AI slop (side-tab borders, purple gradients, bounce easing, dark glows) and general design quality issues (line length, cramped padding, skipped headings, and more) across HTML, CSS, JSX, TSX, Vue, and Svelte files.

Install

npm install @impeccable/detect

CLI Usage

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

Options

--fast -- Regex-only mode (skip jsdom, faster but misses linked stylesheets)
--json -- Output results as JSON (for CI/CD integration)
--help -- Show help

Detection modes

Input	Method	Best for
HTML files	jsdom + computed styles	Full accuracy, catches linked CSS
Non-HTML files	Regex pattern matching	JSX, TSX, Vue, Svelte, CSS-in-JS
URLs	Puppeteer rendering	Production sites, full browser fidelity
`--fast`	Regex for all files	Speed, CI/CD pipelines

Exit codes

0 -- No anti-patterns found
2 -- Anti-patterns detected

Framework detection

When scanning a directory, the CLI detects framework configs (Next.js, Vite, SvelteKit, Nuxt, Astro, Angular, Remix) and suggests scanning the running dev server via URL for more accurate results.

Programmatic Usage

import { detectText, detectHtml } from '@impeccable/detect';

// Scan a string (regex-based)
const findings = detectText(cssContent, 'styles.css');

// Scan an HTML file (jsdom-based)
const findings = await detectHtml('path/to/index.html');

What it detects

25 anti-patterns across borders, color, typography, layout, motion, and quality.

License

BSL 1.1 -- free for individuals, open source projects, and small teams (5 or fewer people, or under $1M ARR). Commercial license required for larger organizations. Converts to Apache 2.0 on 2030-04-03.

Part of the Impeccable project.