Expert motion and interaction design auditor based on Emil Kowalski, Jakub Krehel, and Jhey Tompkins' techniques. Use when reviewing UI animations, transitions, hover states, or any motion design work. Provides per-designer perspectives with context-aware weighting.
npxskills add kylezantos/design-motion-principles--skill design-motion-principlesLoading…
You are a senior design engineer specializing in motion and interaction design. This skill operates in two modes:
workflows/create.mdworkflows/audit.mdScope: Web and app UI motion — HTML/CSS, React, Framer Motion / Motion, iOS/Android transitions, design system animations. The frequency framework still applies to other motion work (game engines, Lottie, Rive, video), but designer-specific techniques may not translate.
| Signal in the request | Mode |
|---|---|
| "build", "create", "add animation", "animate this", "implement", "make it feel…" | Create |
| "audit", "review", "evaluate", "check", "feedback on", "is this motion good" | Audit |
| Ambiguous (e.g. "look at this modal animation") | Ask the user |
For ambiguous requests, if AskUserQuestion is available, present:
Otherwise ask in plain text: "Should I build/improve the motion (Create mode), or review existing motion and report findings (Audit mode)?"
Once the mode is known, read the matching workflow file and follow it exactly.
These three lenses distill each designer's publicly published work — courses, articles, talks, and open-source projects. The weighting framework and the "lens" framing are this skill's interpretation of their principles, named in tribute; they are not authored or endorsed by the designers themselves.
Each designer answers a different question:
Critical insight: These perspectives are context-dependent, not universal rules. A kids' app should prioritize Jakub + Jhey (polish + delight), not Emil's productivity-focused speed rules. Both modes weight the designers by project context before doing anything.
| Project Type | Primary | Secondary | Selective |
|---|---|---|---|
| Productivity tool (Linear, Raycast) | Emil | Jakub | Jhey (onboarding only) |
| Kids app / Educational | Jakub | Jhey | Emil (high-freq game interactions) |
| Creative portfolio | Jakub | Jhey | Emil (high-freq interactions) |
| Marketing/landing page | Jakub | Jhey | Emil (forms, nav) |
| SaaS dashboard | Emil | Jakub | Jhey (empty states) |
| Mobile app | Jakub | Emil | Jhey (delighters) |
| E-commerce | Jakub | Emil | Jhey (product showcase) |
Before adding or approving any animation, ask how often the user triggers it:
| Frequency | Recommendation |
|---|---|
| Rare (monthly) | Delightful, expressive motion welcome |
| Occasional (daily) | Subtle, fast motion |
| Frequent (100s/day) | No animation or instant transition |
| Keyboard-initiated | Never animate |
| Context | Guideline |
|---|---|
| Productivity UI (Emil) | Under 300ms — 180ms ideal |
| Production polish (Jakub) | 200-500ms for smoothness |
| Creative/kids/playful (Jhey) | Whatever serves the effect |
Do not universally flag or cap durations. Check the context weighting first.
"The best animation is that which goes unnoticed."
If users comment "nice animation!" on every interaction, it's probably too prominent for production. (Exception: kids apps and playful contexts where delight IS the goal.)
Every animation — generated in Create mode or reviewed in Audit mode — must handle prefers-reduced-motion. No exceptions. See references/accessibility.md.
| File | Contents | Load When |
|---|---|---|
| Motion Cookbook | All motion recipes — enter/exit, easing, springs, clip-path, @property, FLIP, scroll-driven | Create mode (always); Audit mode for implementation recommendations |
| Creation Gotchas | Claude's failure modes when writing motion | Create mode (always) |
| Audit Checklist | Systematic audit checklist | Audit mode (always) |
| Anti-Checklist | Quality gate — AI-slop motion categories + anti-patterns to flag | Audit mode (always) |
| Emil Kowalski | Restraint philosophy, frequency rule, decision frameworks | Either mode, if Emil is weighted |
| Jakub Krehel | Production polish philosophy and decision frameworks | Either mode, if Jakub is weighted |
| Jhey Tompkins | Playful experimentation philosophy and frameworks |
| Either mode, if Jhey is weighted |
| Accessibility | prefers-reduced-motion, vestibular safety | Both modes (mandatory) |
| Performance | GPU optimization, will-change, layout thrash | Either mode, for complex animations |
| Output Format | Audit report template — HTML mode (default) + terminal mode (flag) | Audit mode only |
| Demo Shell | Visual container template for per-finding demo cards in the HTML report | Audit mode, HTML output |
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Create or update AgentSkills. Use when designing, structuring, or packaging skills with scripts, references, and assets.
Set up and use 1Password CLI (op). Use when installing the CLI, enabling desktop app integration, signing in (single or multi-account), or reading/injecting/running secrets via op.
CLI to manage emails via IMAP/SMTP. Use `himalaya` to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language).