Build multiple genuinely different versions of a UI piece you describe, rendered behind a visual picker so you can flip through them live and promote the one that feels right. Only runs when explicitly invoked; it does not trigger on its own.
Install
npx skills add emilkowalski/skills --skill prototypenpx skills add emilkowalski/skills --skill prototype -a claude-code -gnpx skills add emilkowalski/skills --skill prototype -a codex -ggemini skills install https://github.com/emilkowalski/skills.git --path skills/prototypegh skill install emilkowalski/skills prototypegit clone --depth 1 https://github.com/emilkowalski/skills /tmp/emilkowalski__skills
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/emilkowalski__skills/skills/prototype ~/.claude/skills/prototype # Claude Code
cp -R /tmp/emilkowalski__skills/skills/prototype ~/.agents/skills/prototype # Codex, Cursor, Gemini CLI, Copilot, OpenCode