Rendition Profiles

A game does not accept "a GLB". It accepts a file with a particular skeleton, particular animation clips, a size limit, embedded textures. A rendition profile is how a game says this once, in a form both people and programs can read.

What a profile is

A profile is a selector, a requirements document and the name of a builder.

Field	Example	Meaning
platform / profile	desktop / humanoid-glb-v1	The selector games and creators refer to
version	1	Bumped when the requirements change
ownerProjectId	omoba	The game that defined it
acceptedBy	["omoba"]	Games that take renditions of this profile
builder	omoba-humanoid-glb or none	What produces the file
format	glb	The file family of the rendition
requirements.source	VRM 0 or 1, up to 50 MB, humanoid	What the creator's upload must be
requirements.rendition	binary glTF 2, self-contained, at least one skin with joints, clips idle, walk, attack, cast, death	What the file handed to the game must be

Profiles are public:

GET /v1/profiles
GET /v1/profiles/desktop/humanoid-glb-v1

A profile belongs to the protocol, not to one game. If your game can load what desktop / humanoid-glb-v1 describes, accept that profile and every avatar already prepared for it becomes a candidate for your game. You only approve submissions.

Profiles today

Selector	Defined by	Builder	In short
desktop / humanoid-glb-v1	Omoba	omoba-humanoid-glb	VRM in, GLB out with five retargeted animation clips
universal / vrm-humanoid-v1	Ekza Space	none	The VRM upload is used as it is; the runtime supplies idle and walk
ios / arkit-body-v1	Ekza Mirror	arkit-usdz	VRM in, USDZ out on Apple's 91-joint body skeleton

What the creator sees

Before anything is built, Studio asks the registry what stops an upload from becoming a profile's rendition and shows the answer as a list:

{
  "ok": false,
  "builder": "omoba-humanoid-glb",
  "issues": [
    {"code": "source_format", "message": "The upload must be a VRM model (vrm0, vrm1); it has no VRM metadata."},
    {"code": "source_too_large", "message": "The file is 61.2 MB; the limit is 50 MB."}
  ]
}

When the list is empty the creator asks for the rendition, a worker builds it, and the creator submits it to the game.

Builders: the game owns its rules

builder: none means the upload itself is handed to the game after the same checks. Any other builder is a command that lives in the game's repository. The registry runs it; the game keeps both its requirements and the code that satisfies them. Connecting a new game is a profile and a command, not a change to the registry.

The contract is deliberately small:

<command> --source <file> --output-dir <dir>

• stdout carries exactly one JSON document;
• exit 0: {"ok": true, "format": "glb", "assetPath": "<dir>/<sha256>.glb", "sha256": "...", "sizeBytes": 1885072, "report": {...}};
• exit 2: {"ok": false, "issues": [{"code": "...", "message": "..."}]} when the avatar cannot become a valid rendition;
• no network access, nothing written outside the output directory, output named by its content hash so a repeated build is idempotent.

Studio runs external processors in a disposable Docker container: no network, read-only root filesystem and explicitly mounted code/assets, read-only source, resource limits, and one writable directory for the attempt. The runtime image must be installed in advance and pinned by digest. Missing isolation configuration fails the build; it never falls back to a host process. Then it verifies the path, the hash and the size and applies requirements.rendition itself. A builder is never trusted blindly. A failed build records a short reason without file system paths, and the creator can ask again.

Bringing your game to Ekza

1. Decide whether an existing profile fits. If it does, ask for your project to accept it.
2. Otherwise write a requirements document and, if the upload has to be transformed, a builder that follows the contract above. Keep both in your repository.
3. Register the project and its owners with the Ekza operator.
4. Read your approved avatars from the catalogue and let your server decide admission. See Game Integration.

Self-service registration of projects and profiles is planned; today an operator adds them.