This is for those moments when you need UI feedback to feel immediate, not animated. Button presses, toggles, checkboxes, anything under 100ms where users shouldn't consciously see motion, just feel responsiveness. The guidance here is smart about what actually works at instant speeds: subtle scale changes (0.95-1.05), ease-out only, linear paths, skip anticipation and follow-through entirely. It's basically telling you that most animation principles don't apply when you're working in 1-3 frames at 60fps. The key insight is right: at this speed you're confirming actions, not communicating through motion. Use this when perceived performance matters more than fancy transitions.
npx skills add https://github.com/dylantarre/animation-principles --skill instant-0-100ms