Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/dylantarre/animation-principles/state-changesnpx skills add dylantarre/animation-principles --skill state-changesgit clone --depth 1 https://github.com/dylantarre/animation-principlesWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/dylantarre/animation-principles/state-changes)<a href="https://agentmods.dev/skills/dylantarre/animation-principles/state-changes"><img src="https://agentmods.dev/badge/skills/dylantarre/animation-principles/state-changes.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00032 | $0.00693 |
| Opus 5 | $0.00016 | $0.00347 |
| Sonnet 5 | $0.00006 | $0.00139 |
| Haiku 4.5 | $0.00003 | $0.00069 |
Grade A, and why
state-changes scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 84 lines — stays where its author put it; the contents beside it link to each section on GitHub.
State Change Animations
Apply Disney's 12 principles when elements transform without leaving.
Principle Application
Squash & Stretch: Elements compress before expanding. A toggle switch squashes 5% before sliding.
Anticipation: Wind up before the change. Slight reverse movement (2-3px) before expanding.
Staging: Keep transformations centered on user focus. Don't let state changes distract from the interaction point.
Straight Ahead vs Pose-to-Pose: Define exact states. Button has rest, hover, active, disabled - each precisely designed.
Follow Through & Overlapping: Parts transform at different rates. Icon rotates before label fades in.
Slow In/Slow Out: Use ease-in-out for bidirectional changes: cubic-bezier(0.4, 0, 0.2, 1).
Arcs: Rotating elements follow natural arcs. Chevrons rotate on their center point, not linearly.
Secondary Action: Pair the primary change with supporting motion. Toggle sliding + color shift + icon swap.
Timing:
- Micro-states: 100-150ms (checkbox tick, radio fill)
- Standard states: 150-250ms (toggles, accordions)
- Complex states: 250-400ms (multi-part transformations)
Exaggeration: Overshoot slightly on state changes. Toggle goes 2px past, then settles.
Solid Drawing: Maintain element integrity during transformation. No distortion that breaks visual consistency.
Appeal: State changes should feel satisfying. Users clicked with intent - reward that intent.
Timing Recommendations
| State Change | Duration | Easing | Notes |
|---|---|---|---|
| Checkbox | 150ms | ease-out | Tick draws in |
| Toggle Switch | 200ms | ease-in-out | Overshoot slightly |
| Radio Button | 150ms | ease-out | Scale in from center |
| Accordion | 250ms | ease-in-out | Height + rotation |
| Tab Switch | 200ms | ease-in-out | Indicator slides |
| Button Active | 100ms | ease-out | Scale to 0.97 |
| Card Expand | 300ms | ease-in-out | All properties together |
Implementation Pattern
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 5d ago First seen · 84 lines · 32 tokens per session scan A f6a65edc59fc
state-changes is a skill published in the GitHub repository dylantarre/animation-principles (79 stars, last pushed 8mo ago), licensed MIT. It adds 32 tokens to every session and 693 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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