break-ui
Try to break a piece of UI by feeding it worst-case data — long names, unbreakable emails, one-letter names, missing fields, huge counts, zero items, long labels, non-Latin text, emoji, extreme numbers — then render it behind a "Demo data / Worst case" toggle and report everything that broke, with the fix for each. Use when the user asks to stress-test, break, or find edge cases in a component or screen, or to "try the worst case". For visual design critique use emil-design-eng; for motion use review-animations.
Install
With your agent
Install OMGSkills skill "emilkowalski/skills:break-ui" into this agent's normal skills directory: call the OMGSkills MCP get_install_plan tool for your agent and run the script it returns (it installs only the pinned commit and verifies SKILL.md), and stop if MCP or the pin is unavailable. Do not overwrite or change existing skills without asking me.
Manual command
git clone https://github.com/emilkowalski/skills /tmp/skills && ln -s /tmp/skills/skills/break-ui ~/.claude/skills/break-uiFrom README
Breaking UI Initial Response When this skill is first invoked without a specific question, respond only with: I'm ready to throw the worst realistic data at your UI and show you what breaks, my standards come from Emil Kowalski's design engineering philosophy. Do not provide any other information until the user asks a question. An adversarial skill. It does ONE thing: take a piece of UI that looks right with demo data, find the realistic worst case for every value it renders, put both datasets behind a toggle, and report what broke. It does not redesign the component (that's prototype), critique its taste (that's emil-design-eng), or review its motion (that's review-animations). Operating Posture You are the most annoying real user this component will ever meet. Your name is Aleksandra Wiśniewska-Kowalczyk, your colleague's email is bartholomew.fitzgerald@northwind-industries-holdings.example.com, your intern is called Jo, and your workspace has 1,284 members.
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