wjgoarxiv/agentvfx

Music-reactive VFX, directed by your coding agent.

agentvfx.vercel.app · Showreel · Install · Try it in your browser · Gallery · How it works · Flash safety

You describe the clip. The agent writes a short FX score (template, preset, a few parameters, which part of the music drives what), renders it with WebGL2 in headless Chrome, encodes it with ffmpeg and checks every frame for dangerous flashing before it shows you anything. Backgrounds come from procedural Blender scenes. The same templates also run live in a web page, and the site runs them in yours.

🎬 Showreel

📦 Install

agentvfx is a single agent skill, so any agent that reads skills can use it. The quickest way works for most of them:

npx skills add wjgoarxiv/agentvfx

Or use your agent's own plugin command:

Other agents, or no installer

Clone the repository and point your agent at AGENTS.md. It names the skill file and the folder to run commands from.

git clone https://github.com/wjgoarxiv/agentvfx

The repository also carries plugin manifests for Cursor, Kimi, Antigravity and Devin (.cursor-plugin/, .kimi-plugin/, .antigravity-plugin/, .devin-plugin/).

Then ask for something like "a 4-second neon lattice that hits on the kick of this track, looping, 1080p".

Requirements

• Node.js 20 or newer. There is no npm install step and no runtime dependency.
• Google Chrome or Chromium with GPU WebGL2 (CHROME_PATH to override)
• ffmpeg and ffprobe (FFMPEG_PATH, FFPROBE_PATH)
• Blender 5.x, only for background plates (BLENDER_PATH)

🕹 Try it in your browser

The site at agentvfx.vercel.app runs the templates live with WebGL2. Nothing is uploaded and no sound plays unless you pick a file of your own.

Paste the copied prompt into your agent and it renders the full clip on your machine.

✨ What it makes

🖼 Gallery

Twenty reels from the site, rendered by the skill at 1080p and looped silently: four seconds forward, then backward. Click one to open its page with the prompt and FX score that made it. A music track drove the motion while rendering; no audio is distributed, and every score points at your-track.mp3, so any track works.

Warning

signal-cut is a strobe cut on purpose and exceeds the WCAG 2.3.1 flash limit. It shows as a still here; its page asks before it plays.

Families

Before and after

Formats

One song, many looks

Earlier renders (kept in the 0.3.3 commit): the Blender backdrop, the lattice and 21 collages

These 1280x720 loops left the repository tree in 0.3.4 to keep it small; they stay in the 0.3.3 commit. lattice-vermilion-fine and runner contain flashing red that exceeds common photosensitive-seizure guidelines (WCAG 2.3.1); they are marked ⚠️. Do not show them to viewers who have not been warned.

Backdrop

A procedural Blender scene: a concrete gallery with a CRT wall, built and lit in code.

Lattice

A fine vermilion grid that bends and flares on the kick, laid over the gallery plate.

Collages

Layered typographic compositions in mixed materials. The cells hold still; what is inside them moves with the music.

🔒 What it runs, writes and sends

• Runs: node scripts/vfx.mjs from skills/agentvfx/, which starts headless Chrome or Chromium (driven over --remote-debugging-pipe, no debugging port), ffmpeg/ffprobe to encode and analyse, and Blender 5.x only when a score asks for a background plate.
• Writes: renders, stills and reports into the folder passed as --out, plus a throwaway Chrome profile.
• Sends: nothing. The engine makes no outbound network requests and has no telemetry. The optional live frame server listens on 127.0.0.1 only, on a random port. Clips come from deterministic shader templates, not from a generative model.

🔧 How it works

Engine commands run from skills/agentvfx/:

cd skills/agentvfx
node scripts/vfx.mjs doctor     # checks Chrome, WebGL2, ffmpeg, Blender
node scripts/vfx.mjs list       # templates and presets
node scripts/vfx.mjs render test/fixtures/score-ok.json --out out/first --width 640 --height 360

Then open out/first/stills/sheet.png. For a footage look with the bundled demo media, try templates/brutal/lattice/demo-vermilion.json. SKILL.md covers scores, audio bindings, plates, loops and the web export; references/web.md has the browser API.

⚠️ Flash safety

How flashing is measured and what the gallery passes

Strobe and impact templates can exceed photosensitivity limits on purpose, for stage use. Every render writes a flash audit. broadcast-safe mode enforces the limits, and safeVariant renders a tamed copy beside the original. Templates that can flash ship safeSubstitute values; the site runs them only with those values locked, and keeps flash-capable templates without safe values render-only.

All twenty-nine site reels pass the audit, including across the loop point; signal-cut shows its flash-safe version there. Of the earlier renders, twenty-one pass (cube-wall and tilt-tiles hold for six frames at each turn to stay inside the limit) and the two marked ⚠️ do not.

Live effects carry a flash guard: the browser runtime checks every shown frame with the audit's own detector and never shows a frame that would break the limit. It stops the effect instead, and the page can reset and resume (see the web reference). On the site, all four hero looks and twenty-five flash-rated playground templates, with every slider pushed to three quarters of its range, were captured for ten seconds under scripted pointer input and checked with the same audit. All pass except signal-cut, which showed two single red transitions six seconds apart: no flash within any one second, but the audit counts the pair over the whole capture.

🙏 Credits

• Capture engine adapted from LitClaude lit-typographic-motion and mexicat/pdoom-video (both MIT); see NOTICE.
• Demo footage clip-01.mp4 and clip-02.mp4: public-domain films from the Internet Archive (sources). beat-132.mp3 is generated by scripts/make-beat.mjs.
• Fonts are not bundled. The collages name Monument Extended, Pretendard and MesloLGS NF; without them the text falls back to generic families and looks different from the gallery.

📄 License

agentvfx is licensed under the Apache License 2.0. You may use, change and share it, commercially too, as long as you keep the licence and the NOTICE file with any copy you hand on. Releases up to 0.3.4 were published under earlier terms and keep their own LICENSE file.

A credit is appreciated, not required. Every render burns a small agentvfx credit into a corner of the frame by default; switch it off with "credit": { "overlay": false } in the score. If you would like to credit agentvfx in a description or credits, this line is also written to CREDIT.txt next to every film:

Made with agentvfx by Woojin Go - https://github.com/wjgoarxiv/agentvfx

The licence gives no right to use the name "agentvfx" or its logo beyond saying truthfully where a work comes from (Apache-2.0, section 6). The folder that export-web writes carries its own LICENSE and NOTICE; keep them with the files.

한국어 요약: agentvfx는 Apache License 2.0을 따릅니다. 상업적 사용을 포함해 자유롭게 쓰고, 고치고, 배포할 수 있습니다. 다른 사람에게 넘길 때는 LICENSE와 NOTICE 파일을 함께 넘겨 주세요. 렌더 화면 모서리에 기본으로 들어가는 작은 agentvfx 크레딧은 끌 수 있고, 크레딧 표기는 의무가 아니라 부탁입니다.

The parts adapted from mexicat/pdoom-video keep their MIT licence (NOTICE lists the files). To cite agentvfx in a paper or write-up, use CITATION.cff.