What It Is
A reusable evaluation skill packaged for Claude Code that takes any website URL and runs it through Jakob Nielsen’s ten usability heuristics — visibility of system status, match between system and the real world, user control and freedom, consistency and standards, error prevention, recognition over recall, flexibility and efficiency, aesthetic and minimalist design, error recovery, and help / documentation.
The output is a professional PDF audit report with executive summary, per-heuristic findings (Pass / Partial / Fail), evidence-based observations, and a priority matrix ranking issues from Critical to Cosmetic.
→ github.com/mertony8/claude-skills/tree/main/ux-heuristic-evaluator
How It Works
Five phases the skill walks through, end to end:
- Phase 0 — Scope. Asks whether to evaluate the full site (8–12 representative pages) or a single page (faster, narrower coverage).
- Phase 1 — Discovery & crawl. Uses Claude in Chrome to map the site, prioritise meaningful pages (homepage, navigation, forms, content, errors, help), and crawl them.
- Phase 2 — Page-level inspection. For each page: accessibility tree, page text, screenshots, interactive elements, link graph.
- Phase 3 — Heuristic evaluation. Scores each of the 10 heuristics with concrete evidence and severity-rated issues.
- Phase 4 — Report generation. Renders a PDF (reportlab) with cover page, executive summary, per-heuristic findings, and a prioritised issue matrix.
Why I Built It
Heuristic evaluations are the most reliable cheap-and-fast quality check in the design toolkit, and the easiest one to skip when the schedule tightens. Encoding the method as a skill removes that excuse: any reviewer (designer, PM, engineer) can run a first pass without booking a workshop or hiring a consultant.
It’s also the simplest possible argument for what a “skill” is when software does the work. The method is well-defined; the steps are mechanical; the variability is in the evidence and the writing. That’s the shape of work agents handle well — but only if the policy around them (scope, crawl strategy, evidence collection, output format) is encoded explicitly.
Sample Reports
The repo includes real reports generated by the skill against public sites:
- CoinDive — crypto data platform · 7 Pass, 2 Partial, 1 Fail · highlights: excellent system status, blank 404
- Wikipedia — encyclopedia portal · 5 Pass, 4 Partial, 0 Fail · highlights: functional minimalism, accessibility gaps
- Notion (marketing) — SaaS homepage · 8 Pass, 2 Partial, 0 Fail · highlights: enterprise-grade UX, 49% images missing alt text
- Notion (app, logged in) — productivity app · 9 Pass, 1 Partial, 0 Fail · highlights: near-perfect, minor accessibility gaps
The PDFs live in examples/ in the repo.
Requirements
- Claude Code with Claude in Chrome (browser automation tools)
- Computer Use enabled — for Python /
reportlabPDF generation - Public URL — anything Chrome can reach
Status
v1 shipped, open-source. Iterating as new sites get evaluated and the report format gets pressure-tested. Issues, PRs, and “run this on my site” requests welcome on GitHub.