About animation-principles
A skill for reviewing how UI motion is staged across controls, lists, overlays, and entrances. It checks press feedback, deformation, stagger, and focus, then reports findings without making changes.
Key features
- 01Checks interactive press feedback
- 02Reviews deformation and scale
- 03Checks list stagger timing
- 04Evaluates focal-point staging
- 05Reviews overlay dimming and stacking
Use cases
- 01Reviewing motion on interactive controls
- 02Checking animated list entrances
- 03Evaluating overlay and modal motion
Install
Copy the command and run it in a terminal.
npx skills add https:/After installing, type/animation-principlesin Claude Code to confirm it loaded.
Bundled filesagents/openai.yaml
Details
From the project READMEAnimation principles
This skill reviews how motion is staged once the timing function is chosen. It checks press feedback, deformation, stagger and focus.
Every check is a pair. The broken line sits beside the line that replaces it.
Press scale, squash and stagger amounts below are exact. A project that omits press feedback on a control is a finding. A project that uses one consistent scale near 0.98 is not. Curves, the 300ms cap and context-menu entrances belong to timing-functions. Exit mounting belongs to exit-animations.
When to use
Use this when adding or reviewing animation on controls, lists, overlays or entrances. Use timing-functions first when the question is spring versus easing. Use exit-animations when a component fails to leave the tree.
1. Read the motion in scope
Read the files the user named. If none are named, ask which surfaces to review. Note each animated element and whether it is a press, a list entrance, an overlay or background decoration.
2. Check staging
Similar controls share one duration. A primary button at 200ms and a secondary button at 150ms is timing-consistent.
An interactive control needs an active scale. The published press scale is 0.98. Squash and stretch stay inside 0.95 to 1.05. whileTap of 0.8 is physics-subtle-deformation.
Stagger stays under 50ms per item. staggerChildren: 0.03 passes. 0.15 is physics-no-excessive-stagger.
Only one element animates prominently at a time. That is staging-one-focal-point. A modal or dialog dims what is behind it, as in background: var(--black-a6), which is staging-dim-background. A tooltip or overlay that can paint underneath siblings is staging-z-index-hierarchy.
Springs used for overshoot, ease curves and the 300ms cap are timing-functions. Cite that skill beside a duration finding. Do not restate its curve table here.
3. Report and stop
Write the findings, then the summary table. Do not restyle the motion while reporting unless the user asked for a fix.
The pair
Every check is a pair. The broken line sits beside the line that replaces it.
| Rule | Broken | Replacement |
|---|---|---|
timing-consistent | .button-primary { transition: 200ms } and .button-secondary { transition: 150ms } | Both controls at transition: 200ms |
physics-active-state | .button:hover { background: var(--gray-3) } and no :active | .button:active { transform: scale(0.98) } |
physics-subtle-deformation | whileTap={{ scale: 0.8 }} | whileTap={{ scale: 0.98 }} |
physics-no-excessive-stagger | staggerChildren: 0.15 | staggerChildren: 0.03 |
staging-one-focal-point | Two siblings both animate={{ scale: 1.1 }} | One element carries the entrance |
staging-dim-background | .overlay { background: transparent } | .overlay { background: var(--black-a6) } |
staging-z-index-hierarchy | .tooltip {} with no stacking | .tooltip { z-index: 50 } |
Reporting
Severity. Use the ladder in this skill. Do not raise a preference to HIGH.
Verification. Read the declared values in the files in scope. A browser is optional. Mark any check you could not run as Not verified.
Format. One finding per root cause:
file:line - [rule-id] what is wrong
Then a summary:
| Rule | Count | Severity |
|---|
Block when any HIGH remains. Approve otherwise, and leave lesser rows in the table. Never Approve a file you did not read. With nothing to report, say "No actionable findings" and list what was not verified.