Kodecz: an open-source video editor made for AI agents
Article by Pedro Henrique Lahr
Kodecz is an open-source video editor made for AI agents, and as of today, November 1, 2026, anyone can download and use it. The video is a web page that renders to MP4, on the graphics card or on the processor alone. On a short test video, Kodecz used 10 times less processor than Remotion and handed over the file 3 times sooner. On a longer, real video, the gap reached 15 to 17 times.
What is Kodecz?
It is a program that turns a web page into a video. You (or your agent) write the video in HTML, CSS and JavaScript, the same languages web pages are made of. It can have animated text, charts, 3D drawings, filmed footage and music. Kodecz draws the page frame by frame and gives you an MP4 with the sound already mixed in.
No frame becomes a picture along the way. Other tools take a screenshot of every frame; Kodecz sends the frame straight to the video encoder. That is why it uses less.
What is an AI agent, and why build an editor for one?
An AI agent is a program with artificial intelligence that does tasks on its own: it writes files, runs commands and checks the result. Examples are Claude Code, Codex, Cursor and Gemini CLI.
Ordinary video editors were made for people, who look at the screen and drag pieces along a timeline. An agent cannot see the screen. So Kodecz gives it another way to see:
- A one-frame preview in one to two seconds, so the agent looks at what it wrote instead of guessing.
- Automatic checks that look at every frame and flag things like text over a face, a caption breaking onto two lines or too little contrast with the background. The answer names the frame and the reason, with a picture of the problem.
- Editing blocks (captions, zoom, transition, title card, chart, counter...), each explained in a plain file, with a right and a wrong example.
The agent writes, previews, checks and fixes before you look.
Do I need a graphics card?
No. Kodecz uses whatever the machine has:
- With an NVIDIA card (GPU), the frame stays on the card and goes straight to its encoder.
- Without one, the processor (CPU) paints the frame and hands it straight to the encoder, without turning it into an image.
The same video folder works on both paths, frame for frame.
How much faster is it?
On a 1080p video with 150 frames, on an RTX 5090 card:
| Remotion | Kodecz | |
|---|---|---|
| Processor time | 43.7 s | 4.4 s |
| Time until the file is ready | 13.6 s | 4.6 s |
On a longer 74.7 second production video, the gap was 15 to 17 times less processor.
Where are the full numbers?
We published two papers with the launch:
- The engine: how the page becomes video without screenshots, measured against Remotion. Summary in Turning a web page into video without screenshots; paper at doi.org/10.6084/m9.figshare.34880682.
- The agents: where they go wrong when making video and how Kodecz checks it, with the 5,007-case Kodecz Bench. Summary in AI agents making video; paper at doi.org/10.6084/m9.figshare.34880928.
How do I install it?
For now Kodecz runs on Linux, with Node 24 and ffmpeg. The installer checks the system, installs what is missing and renders a test video:
git clone https://github.com/konecz/kodecz && cd kodecz && ./instalar.sh
Or ask your agent: "Install Kodecz (github.com/konecz/kodecz) and make my first video."
More on the Kodecz page and in the repository.
Frequently asked questions
Is Kodecz free? Yes. The code is open, under the Apache-2.0 license, which also allows use in companies.
Which agents can use Kodecz? Any agent that can write files and run commands: Claude Code, Codex, Cursor, Gemini CLI or your own. Nothing in it is tied to one vendor.
Is Kodecz an alternative to Remotion? Yes. Both turn code into video. Remotion asks for React components; Kodecz takes any web page.
Who made it?
Kodecz was created by Pedro Henrique Lahr and Vanessa Cristine at Konecz.
How to cite the papers: Lahr, Pedro Henrique. Kodecz: rendering web pages as video without screenshots, on the GPU and on the CPU, with a declared timeline and deterministic frames. Figshare, 2026. https://doi.org/10.6084/m9.figshare.34880682. And Lahr, Pedro Henrique. Kodecz: a video editor built for AI agents, how agents fail when they write video as code, and how to check it from inside the render. Figshare, 2026. https://doi.org/10.6084/m9.figshare.34880928