gsap-web

gsap-web is a skill for Claude Code from iart-ai/web-animation-skills. It costs 146 tokens per session (3,221 once invoked), scanned A, original, MIT.

Guidance for GSAP, a JavaScript library for creating timed animations in web pages. It covers sequences, scroll-controlled motion, text reveals, and changes in an element's position or size.

In plain words
What is it for?
Use it to build pinned or horizontal scrolling sections, parallax effects, animated hero sections, split-text reveals, and layout transitions.
Why use it?
It helps with animations that need coordinated timing, precise easing, or movement linked to the user's scrolling.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the web-animation-skills plugin — 9 skills shipped together

Good fit Use it to build pinned or horizontal scrolling sections, parallax effects, animated hero sections, split-text reveals, and layout transitions.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/iart-ai/web-animation-skills/gsap-web
Install

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.

Any agent
npx skills add iart-ai/web-animation-skills --skill gsap-web
Clone the repo
git clone --depth 1 https://github.com/iart-ai/web-animation-skills

Made for: Claude Code.

Or install web-animation-skills, the plugin that ships this one along with the rest of its 9 skills.

Wrote 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.

agentmods badge for gsap-web

README.md
[![agentmods](https://agentmods.dev/badge/skills/iart-ai/web-animation-skills/gsap-web/github.svg)](https://agentmods.dev/skills/iart-ai/web-animation-skills/gsap-web)
Your own site
<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.

agentmods 80×15 button for gsap-web

Your own site · 80×15
<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>
Per session 146 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,221 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 23 Jun 2026
  • Snyk warn 23 Jun 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce 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

Measured 11d ago against content hash 9c52294210b3, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

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.

The scan reads SKILL.md. This mod also ships 1 executable file (examples/hero-timeline.js), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

  • gsap-web — 100% identical, 0 lines differ
skills/gsap-web/SKILL.md · 226 lines

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 via tl.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).

Read the full file on GitHub · 226 lines

Files

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.

Changes

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.

  1. 11d ago First seen · 226 lines · 146 tokens per session scan A 9c52294210b3

Subscribe to this mod's changes

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.

Related

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…

heygen-com/hyperframes · 139 tokens

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…

MustBeSimo/cinematic-scroll-skill · 78 tokens

web-imagegen-prompting

Write image prompts with crop/placement intent.

TheGoat395/Codex-Skills · 16 tokens

web-image

A way to create PNG images by describing their layout with HTML and CSS and rendering it in a browser.

whyubel1eve/web-image-skill · 511 tokens

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…

MustBeSimo/cinematic-scroll-skill · 78 tokens

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…

ngocsangyem/MeowKit · 106 tokens