animation-principles
The animation-principles skill provides structured guidance for implementing motion design in user interfaces, covering easing curves, duration ranges, and choreography techniques. Use this skill when designing UI animations to ensure interactions feel natural, responsive, and purposeful rather than decorative, with specific recommendations for entrance, exit, emphasis, and transition effects along with performance considerations.
git clone --depth 1 https://github.com/Owl-Listener/designer-skills /tmp/animation-principles && cp -r /tmp/animation-principles/interaction-design/skills/animation-principles ~/.claude/skills/animation-principlesSKILL.md
# Animation Principles You are an expert in applying motion design principles to create purposeful UI animations. ## What You Do You apply animation principles to make interfaces feel natural, guide attention, and communicate state changes. ## Core UI Animation Principles ### Easing - Ease-out: decelerating (entering elements) - Ease-in: accelerating (exiting elements) - Ease-in-out: both (moving between positions) - Linear: only for continuous animations (progress bars) ### Duration - Micro (50-100ms): button states, toggles - Short (150-250ms): tooltips, fades, small movements - Medium (250-400ms): page transitions, modals - Long (400-700ms): complex choreography ### Motion Principles - **Purposeful**: every animation communicates something - **Quick**: faster is almost always better in UI - **Natural**: follow physics (acceleration, deceleration) - **Choreographed**: related elements move in coordinated sequence - **Interruptible**: animations can be cancelled mid-flight ## Animation Types - **Entrance**: fade in, slide in, scale up - **Exit**: fade out, slide out, scale down - **Emphasis**: pulse, shake, bounce - **Transition**: morph, crossfade, shared element - **Loading**: skeleton shimmer, spinner, progress ## Stagger and Sequence - Stagger related items by 30-50ms each - Lead with the most important element - Limit total sequence duration to under 700ms - Use consistent direction for related movements ## Best Practices - Support prefers-reduced-motion - Don't animate for the sake of it - Test on low-powered devices - Keep animations under 400ms for responsive feel - Use will-change or transform for performance
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Plan accessibility testing — assistive technologies, participant criteria, WCAG coverage, and session protocol. Use when scheduling testing with real AT users. Not for evaluating a design yourself — use `accessibility-audit` (design-systems).
Apply the Aesthetic-Usability Effect — polished, consistent interfaces are perceived as more usable and forgive minor friction. Use when justifying visual polish or diagnosing why a functional design tests badly. For emotional resonance specifically, use `interfaces-that-feel` (interaction-design).
Cluster many qualitative data points into themes and insight statements. Use when synthesising across multiple sessions or sources. For a single transcript use `summarize-interview`; for one segment's inner state use `empathy-map`.
A practitioner's toolkit for thinking and communicating as a designer in a business context — reading financials, mapping competitive landscapes, and defending design decisions in the language of value.
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Craft a portfolio case study with narrative arc, process evidence, and outcomes. Use when telling a project's story to an external audience. For an internal stakeholder deck, use `presentation-deck`.