## Summary - **New skill:** **`marker-highlight`** — integrates [MarkerHighlight.js](https://github.com/Robincodes-Sandbox/marker-highlight) into HyperFrames compositions. Canvas-based animated text highlighting with 5 drawing modes: marker pen, circle, burst, scribble, and sketchout. - **Studio fix:** added missing `captionSync` to useEffect dependency array (oxlint exhaustive-deps) - **Studio fix:** `loadOverrides` now checks `res.ok` before parsing, preventing 404 console noise on projects without captions ## Skill details The skill documents the non-obvious GSAP integration pattern discovered during development: 1. **One highlighter per container** — the library clears ALL `.highlight` divs from the shared parent on init, so multiple instances on sibling marks conflict 2. **`data-color`** **\+** **`data-original-bgcolor`** — prevents the CSS background-color flash that occurs when the library reads and clears the mark's background 3. **Canvas pre-draw + clear + reanimate** — `animate: false` pre-draws statically, canvases are hidden, then cleared and shown with `reanimateMark()` at trigger time for clean animated reveals 4. **`onReverseComplete`** **for rewind** — hides highlight divs when the timeline seeks backward past the trigger point ## Test plan - [ ] `npx hyperframes lint` passes on test-composition - [ ] Studio preview shows marker highlight on "something" at 1s, circle on "love" at 2.2s - [ ] Rewind past trigger points hides highlights - [ ] No 404 console errors for caption-overrides.json on non-caption projects [Screen Recording 2026-04-02 at 1.56.30 AM.mov <span class="graphite__hidden">(uploaded via Graphite)</span> <img class="graphite__hidden" src="https://app.graphite.com/user-attachments/thumbnails/53b03f4e-538e-477a-b738-7a033b99a84e.mov" />](https://app.graphite.com/user-attachments/video/53b03f4e-538e-477a-b738-7a033b99a84e.mov) 🤖 Generated with [Claude Code](https://claude.com/claude-code)
Hyperframes
Write HTML. Render video. Built for agents.
Hyperframes is an open-source video rendering framework that lets you create, preview, and render HTML-based video compositions — with first-class support for AI agents via MCP.
Why Hyperframes?
- HTML-native — AI agents already speak HTML. No React required.
- Frame Adapter pattern — bring your own animation runtime (GSAP, Lottie, CSS, Three.js).
- Deterministic rendering — same input = identical output. Built for automated pipelines.
- AI-first design — not a bolted-on afterthought.
Quick Start
npx hyperframes init my-video
cd my-video
Then open the project with your AI coding agent (Claude Code, Cursor, etc.) — it has HyperFrames skills installed and knows how to create and edit compositions.
npx hyperframes preview # preview in browser (live reload)
npx hyperframes render # render to MP4
Requirements: Node.js >= 22, FFmpeg
Documentation
Full documentation at hyperframes.heygen.com — start with the Quickstart, then explore guides, concepts, API reference, and package docs.
How It Works
Define your video as HTML with data attributes:
<div id="stage" data-composition-id="my-video" data-start="0" data-width="1920" data-height="1080">
<video
id="clip-1"
data-start="0"
data-duration="5"
data-track="0"
src="intro.mp4"
muted
playsinline
></video>
<img id="overlay" data-start="2" data-duration="3" data-track="1" src="logo.png" />
<audio
id="bg-music"
data-start="0"
data-duration="9"
data-track="2"
data-volume="0.5"
src="music.wav"
></audio>
</div>
Preview instantly in the browser. Render to MP4 locally. Let AI agents compose videos using tools they already understand.
Packages
| Package | Description |
|---|---|
hyperframes |
CLI — create, preview, lint, and render compositions |
@hyperframes/core |
Types, parsers, generators, linter, runtime, frame adapters |
@hyperframes/engine |
Seekable page-to-video capture engine (Puppeteer + FFmpeg) |
@hyperframes/producer |
Full rendering pipeline (capture + encode + audio mix) |
@hyperframes/studio |
Browser-based composition editor UI |
AI Agent Skills
HyperFrames ships skills that teach AI coding agents (Claude Code, Gemini CLI, Codex, Cursor) how to write correct compositions and GSAP animations. Use these instead of writing from scratch — they encode framework-specific patterns that generic docs don't cover.
Install via CLI (recommended)
# Install all skills (HyperFrames + GSAP) — runs automatically during `hyperframes init`
npx hyperframes skills
# Or install to a specific agent
npx hyperframes skills --claude
npx hyperframes skills --cursor
Or via npx skills add
# HyperFrames skills (hyperframes-compose, hyperframes-captions)
npx skills add heygen-com/hyperframes
# GSAP skills (gsap-core, gsap-timeline, gsap-scrolltrigger, gsap-plugins, gsap-performance, gsap-utils, gsap-react, gsap-frameworks)
npx skills add greensock/gsap-skills
Installed Skills
| Source | Skills | What they teach |
|---|---|---|
| HyperFrames | hyperframes-compose, hyperframes-captions |
HTML composition structure, class="clip" rules, data-* attributes, timeline registration, rendering constraints |
| GSAP | gsap-core, gsap-timeline, gsap-performance, gsap-plugins, gsap-scrolltrigger, gsap-utils, gsap-react, gsap-frameworks |
Core API, timeline sequencing, ScrollTrigger, plugin usage, performance best practices |
In Claude Code, invoke with /hyperframes-compose, /hyperframes-captions, /gsap-core, etc.
Contributing
See CONTRIBUTING.md for guidelines on how to contribute.
License
See LICENSE for details.