This teaches Claude the animation principle of anticipation: every significant action needs a counter-movement first. It's loaded with practical timing formulas (anticipation should be 30-50% of the main action duration, anything over 200ms needs it) and maps the concept across UI design, character animation, and game mechanics. The source draws from Disney animation theory but translates it into concrete rules like "brief anticipation for small actions, extended for major moments" and "bigger wind-up means faster following action can still read clearly." Use it when you need Claude to design interactions that feel intentional rather than jarring. The implementation heuristic alone makes it worth having around.
npx skills add https://github.com/dylantarre/animation-principles --skill anticipation-mastery