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 skills add kyu-n/gdx-claude-skills --skill universal-tween-enginegit clone --depth 1 https://github.com/kyu-n/gdx-claude-skillsWrote 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/kyu-n/gdx-claude-skills/universal-tween-engine)<a href="https://agentmods.dev/skills/kyu-n/gdx-claude-skills/universal-tween-engine"><img src="https://agentmods.dev/badge/skills/kyu-n/gdx-claude-skills/universal-tween-engine/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/kyu-n/gdx-claude-skills/universal-tween-engine"><img src="https://agentmods.dev/badge/skills/kyu-n/gdx-claude-skills/universal-tween-engine.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00117 | $0.02977 |
| Opus 5 | $0.00059 | $0.01489 |
| Sonnet 5 | $0.00023 | $0.00595 |
| Haiku 4.5 | $0.00012 | $0.00298 |
Grade A, and why
universal-tween-engine 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 11d 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 — 241 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Universal Tween Engine (6.3.3)
Quick reference for consumers of aurelienribon.tweenengine. Covers factory construction, accessor registration, defaults/limits, semantic traps, callbacks, pooling lifecycle, and timeline composition. Full method signatures in references/api.md.
Defaults & Limits
| Setting | Default | Override |
|---|---|---|
| Easing equation | Quad.INOUT |
.ease(equation) |
| Path algorithm | CatmullRom spline |
.path(TweenPaths.linear) |
| Combined attributes limit | 3 | Tween.setCombinedAttributesLimit(n) at startup |
| Waypoints limit | 0 | Tween.setWaypointsLimit(n) at startup |
| Callback trigger | COMPLETE only |
.setCallbackTriggers(flags) |
Tween.call() trigger |
START (overrides default) |
.setCallbackTriggers(flags) |
| Duration units | Unitless (matches manager.update(delta)) |
N/A |
| Repeat count | 0 (no repeat) | .repeat(count, delay) or .repeatYoyo(count, delay) |
| Auto-remove from manager | true | TweenManager.setAutoRemove(tween, false) |
| Auto-start on manager add | true | TweenManager.setAutoStart(tween, false) |
| Tween pool initial capacity | 20 | Tween.ensurePoolCapacity(n) |
| Timeline pool initial capacity | 10 | Timeline.ensurePoolCapacity(n) |
Combined attributes limit = 3 means: tweening 4+ float values simultaneously (e.g., RGBA) throws at runtime unless you call Tween.setCombinedAttributesLimit(4) first.
Waypoints limit = 0 means: ANY .waypoint() call throws unless you call Tween.setWaypointsLimit(n) first.
Factory-Only Construction
Tween and Timeline have private constructors. All instances come from internal object pools via static factories.
// Tween factories — NEVER use new Tween()
Tween.to(target, tweenType, duration) // animate from current to target values
Tween.from(target, tweenType, duration) // animate from target values to current (reversed)
Tween.set(target, tweenType) // instantly set values (duration=0)
Tween.call(callback) // timer/callback only — no target needed
Tween.mark() // empty beacon for Timeline sequencing
// Timeline factories — NEVER use new Timeline()
Timeline.createSequence() // children play one after another
Timeline.createParallel() // children play all at once
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 11d ago First seen · 241 lines · 117 tokens per session scan A 0dba56e457d7
universal-tween-engine is a skill published in the GitHub repository kyu-n/gdx-claude-skills (4 stars, last pushed 7mo ago), licensed MIT. It adds 117 tokens to every session and 2,977 once invoked, about $0.0006 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 2026-08-31.
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