Posecode is an open-source, inspectable movement format. A document describes phases, joint targets, timing, and contacts; tools can validate, edit, diff, and render the same movement.

Does Posecode require an AI model?

No. Posecode documents can be written by hand, produced by an animation tool, or drafted by an LLM. Parsing, validation, editing, and rendering are deterministic and do not require an AI model.

Does Posecode guarantee a movement is safe?

No. Posecode constrains authored and IK-generated joint targets to configured reference ranges and reports unresolved reach targets. A simplified rig cannot certify that a whole movement is safe, accurate, or appropriate for a person. It is not medical advice.

Is Posecode free to use?

Yes. Posecode is open source. The specification and core tooling use Apache-2.0; the product-facing renderer, embed, MCP server, eval harness, and playground use AGPL-3.0. A separate commercial agreement is available for closed-source use of AGPL components.

A readable format for human movement

Movement you can inspect.

Posecode turns human movement into structured, editable text for animation tools, LLMs, and web products. Change the source, validate it, and render the same motion in the browser.

Open source + motion → Read the format

Open source Deterministic Human or LLM authored

Source beside motion. The same document opens in the playground. Open it →

superhero-landing.posecode live

01posecode posture "Superhero landing"
02  rig humanoid
03  pose start = standing
04
05  step "Drop into the landing" 0.55s flow:
06    pelvis: hinge 45
07    spine: flex 50
08    hip_right: flex 84
09    knee_right: flex 123
10    ground-lock: foot_right
11    reach: knee_left floor
12    reach: fist_left floor

Drop into the landing Drop over the planted right foot as the left knee and fist descend

Deterministic

Same document, same validated motion.

Inspectable

Joints, timing, contacts, and warnings stay visible.

Built to integrate

Parser, renderer, embed, and LLM tools.

How it works

From source text to usable motion.

01
Describe

Write phases, joint actions, timing, travel, and contacts as readable text.
02
Validate

The parser produces typed movement data, clamps configured ranges, and reports diagnostics.
03
Use

Render it in Three.js, embed a player, or pass the same document through your own tools.

LLM authoring is optional

Write Posecode directly or start with an LLM draft.

A human can author the source, an animation tool can emit it, or an LLM can draft it. The result is still a small document you can read, edit, diff, validate, and render without model inference.

01 / direct

Write the movement

Use the playground, language tooling, or your own editor.

02 / assisted

Draft with an LLM

Give an LLM the authoring guide, then inspect and revise its output.

Movement library

Start from readable source.

Open examples across fitness, rehab, dance, and more. Every movement remains editable text.

For developers

Build on the layer you need.

Adopt the format, compose the runtime packages, or integrate the player into a product.

Define

Keep the movement as readable source.

Open the source beside the movement, change one instruction, and see exactly what changed.

Start with the playground → Explore integrations →

Movement you can inspect.

From source text to usable motion.

Describe

Validate

Use

Write Posecode directly or start with an LLM draft.

Write the movement

Draft with an LLM

Start from readable source.

Build on the layer you need.

Language spec →

Parser + typed IR →

Three.js runtime →

Embed + LLM tools →

Keep the movement as readable source.