Give a Next.js 16 App Router app ONE motion system: a token layer (durations, easings, springs) plus a library of tokenized micro-interactions — entrance/exit, stagger, layout, modal/dropdown/toast/accordion, hover, feedback and route/page transitions. Four modes: Setup (scaffold lib/motion/ from the DESIGN.md motion block), Apply, Audit (find ad-hoc or hardcoded motion), Refine (swap hardcoded values for tokens). Use when the user says "add a transition", "animate this", "aggiungi una transizione / animazione", "page transition", "stagger these cards", "make the modal open nicely", or "audit the motion in this codebase". Refuses outside Next.js 16 web (stack.framework next/monorepo). Not for: React Native motion (use rn-animations-gestures), installing the Motion runtime itself (use module-add motion), or defining the visual palette/type (that is DESIGN.md + design-md-to-app).
transition: / animate={{…}} / @keyframes / a Tailwind duration-[Xms] arbitrary value.module-add motion (this skill routes there for Tier 3).design-md-to-app own visual tokens; this owns *motion* tokens.rn-animations-gestures.phase./plugin install dev-flow@dev-flow # the whole suite
./install.sh --platform claude # or drop dist/transitions.skill into Claude Code