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Motion design foundation - timing, easing, enter/exit patterns, accessibility, performance.
Passed 19 of 25 test cases with the skill, and 13 of 25 without it.
and 4 more in the full report
6 fixed13 passed either way6 still failing0 broke
Tokens, turns and time describe resource use, not a dollar price.
One of 6 test cases the skill fixed. Same model, same prompt, with and without the skill.
In a SwiftUI card dismissal effect, the code currently uses scaleEffect 0.0 when hidden paired with opacity zero. What minimum scale factor should replace 0.0 in scaleEffect?
| Checked | Without skill | With skill |
|---|---|---|
| Sets the hidden state scaleEffect factor to 0.95. | Missed | Passed |
The instructions your model reads when the skill loads.
Version-sensitive. Every API name, SDK gate and browser-support claim below was verified on 2026-09-08 against primary sources. What against, and when, is in
_jutsu/VERSIONS.md. If that date is old, re-verify before acting on a version number.
The foundation. Loaded by every creative skill invocation. Concise rules here. Deep-dive in
references/.
| Context | Duration | Why |
|---|---|---|
| Micro-interaction (toggle, hover, focus) | 100-150ms | Instant feedback, no perceived delay |
| UI transition (modal, drawer, tab switch) | 200-300ms | Smooth but never sluggish |
| Page/route transition | 300-500ms | Establishes spatial narrative |
| Scroll-driven / 3D | Free (progress-based) | Tied to user input, no fixed duration |
Frequency rule: The more often an animation plays, the shorter and subtler it must be. A button hover (1000x/day) = 100ms opacity. An onboarding reveal (1x ever) = 600ms+ full choreography.
| Action | Easing | Why |
|---|---|---|
| Element enters | ease-out / spring | Decelerates into resting position (natural arrival) |
| Element exits | ease-in | Accelerates away (gets out of the way) |
| Element moves between states | ease-in-out | Smooth start and stop |
| Scroll-synced | linear / none | Matches 1:1 with input, no lag perception |
| Bouncy/playful | spring (underdamped) | Overshoot creates life |
| Snappy UI | cubic-bezier(0.2, 0, 0, 1) | Fast start, smooth land |
Exit is always more subtle than enter. Enter: 300ms ease-out, full choreography. Exit: 200ms ease-in, opacity only.
test cases passed, vs 13 / 25 without
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