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 iart-ai/web-animation-skills --skill gsap-webgit clone --depth 1 https://github.com/iart-ai/web-animation-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/iart-ai/web-animation-skills/gsap-web)<a href="https://agentmods.dev/skills/iart-ai/web-animation-skills/gsap-web"><img src="https://agentmods.dev/badge/skills/iart-ai/web-animation-skills/gsap-web/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/iart-ai/web-animation-skills/gsap-web"><img src="https://agentmods.dev/badge/skills/iart-ai/web-animation-skills/gsap-web.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk warn
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 | $0.00146 | $0.03221 |
| Opus 5 | $0.00073 | $0.01611 |
| Sonnet 5 | $0.00029 | $0.00644 |
| Haiku 4.5 | $0.00015 | $0.00322 |
Grade A, and why
gsap-web 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- gsap-web — 100% identical, 0 lines differ
How it starts
The opening of the file, as written. The whole thing — 226 lines — stays where its author put it; the contents beside it link to each section on GitHub.
GSAP for the Web
GSAP (GreenSock Animation Platform) is the workhorse for code-driven web motion: sequenced timelines, scroll-driven storytelling, text reveals, and layout transitions. As of GSAP 3.12+, every plugin (ScrollTrigger, SplitText, Flip, MotionPath, MorphSVG, Draggable, Observer) is 100% free, including for commercial use.
When to use
- Scroll-driven storytelling: pinned sections, parallax, progress scrubbing, horizontal scroll
- Sequenced hero animations and complex multi-element timelines with precise overlap control
- Text reveals split into chars/words/lines (SplitText)
- Layout transitions where an element changes position/size/parent (Flip)
- Any motion needing fine timing control, easing precision, or imperative orchestration
Install and register
import gsap from "gsap";
import { ScrollTrigger } from "gsap/ScrollTrigger";
import { SplitText } from "gsap/SplitText";
import { Flip } from "gsap/Flip";
gsap.registerPlugin(ScrollTrigger, SplitText, Flip);
Plugins MUST be registered before use or they silently no-op. With a bundler, register once at app entry.
Core techniques
Timelines first
Prefer one timeline over many independent tweens — it gives a single playhead, relative positioning, and easy reversal.
const tl = gsap.timeline({ defaults: { ease: "power3.out", duration: 0.6 } });
tl.from(".title", { yPercent: 100, opacity: 0 })
.from(".sub", { y: 20, opacity: 0 }, "-=0.3") // start 0.3s before prev ends
.from(".cta", { scale: 0.9, opacity: 0 }, "<"); // align to prev tween START
Position parameter cheat sheet:
"+=0.5"/"-=0.3"— relative to the end of the timeline (gap / overlap)"<"— start of the previous tween;">"— end of the previous tween"<0.2"— 0.2s after the previous tween's start"myLabel"— at a named label added viatl.addLabel("myLabel")
Use .from() for entrances (animates FROM the given values TO current CSS), .to() for exits, .fromTo() when both ends must be explicit (most robust against re-runs).
What ships with it
5 files 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 · 226 lines · 146 tokens per session scan A 9c52294210b3
gsap-web is a skill published in the GitHub repository iart-ai/web-animation-skills (20 stars, last pushed 2mo ago), licensed MIT. It adds 146 tokens to every session and 3,221 once invoked, about $0.0007 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.
Other skills, from other repositories
hyperframes-animation
All animation knowledge for HyperFrames — atomic motion rules, multi-phase scene blueprints, scene transitions, broader motion-design techniques, AND the seven runtime adapters (GSAP default, plus Lottie, Three.js, Anime.js, CSS keyframes, Web Animations API, TypeGPU). Use for any motion or animation task: pick 2-4…
cinematic-scroll
Design and build cinematic websites, 3D websites, interactive portfolios and product landing pages with scroll-driven storytelling, parallax, text animation and optional Three.js/WebGL scenes. Use for new experiences, motion improvements, scroll audits and storyboards in standalone HTML or an existing app. Includes…
web-imagegen-prompting
Write image prompts with crop/placement intent.
web-image
A way to create PNG images by describing their layout with HTML and CSS and rendering it in a browser.
cinematic-scroll
Design and build cinematic websites, 3D websites, interactive portfolios and product landing pages with scroll-driven storytelling, parallax, text animation and optional Three.js/WebGL scenes. Use for new experiences, motion improvements, scroll audits and storyboards in standalone HTML or an existing app. Includes…
mk:html-video
Render an HTML/CSS/JS template to a local MP4 video by capturing frames with headless Chromium (via Playwright) and encoding them with ffmpeg. Use when "render my animation as a video", "export HTML to MP4", "make a video from my web template", or "capture CSS animation as MP4". NOT for recording live browser…