An open spec for portable avatars, virtual worlds, and game characters. Your look, your data, your server -- not locked inside someone else's platform.
Whether you stream, hang out in virtual worlds, or play games across platforms -- at3d gives your identity a permanent home.
Upload your VRM model to your personal data server once, and every compatible streaming app, social platform, or virtual world can load it directly. No re-exporting, no format wrangling, no uploading the same file to five different services.
The avatar record supports VRM 0.x and 1.0, GLTF models with skeleton metadata for animation retargeting, and thumbnails for quick previews. Apps read the record, pull the blob, and render it.
Not everything is polygons. The parametric avatar format stores appearance as structured data -- palette indices, style IDs, body proportions -- that any app with a matching system can render into its own 2D art style.
This works for Live2D-style VTubers, pixel art games, or any app that generates characters procedurally. A streaming tool reads your palette choices and draws your 2D avatar in its own style. A different app reads the same record and renders something completely different, but recognizably you.
Build a cozy room, a rooftop lounge, or an art gallery and publish it as a scene record. Other users discover it through world records on the network, load it in their app of choice, and drop in at the spawn point.
Scenes include placed objects, lighting, skybox presets, physics settings, and licensing info. World records add connection details, player counts, and visibility modes so social apps can build server browsers and invite flows around them.
Your MMO character is more than a username. The character record holds your level, class, currency, and playtime, while linking out to separate records for stats, equipment, inventory, and achievements.
Switch to a new game and bring your progress along. The new game resolves your AT URI references, reads your stat block, checks your gear, and decides what to honor. You don't start from zero -- you start from you.
Build a character creator app -- web, desktop, or mobile -- and save results directly to the user's data server. The output is a standard avatar record that any at3d-compatible app can read.
Creators can publish VRM or GLTF models with licensing metadata, making community-created avatars discoverable and portable. Users browse, pick a look, and carry it across every platform without the creator needing to integrate with each one individually.
When a game server validates your character data, it publishes a validation record -- a signed attestation that says "this player's stats were earned here and they check out." Other apps can look up those records to decide how much to trust imported data.
No central authority decides what's real. Each app sets its own strictness. A competitive game might only accept data validated by servers it knows. A casual hangout might accept anything. The trust layer is open and federated, just like the protocol underneath.
Publish 3D models to your data server with metadata, thumbnails, and licensing info. Other users can discover your work, preview it, and use it in their own scenes or avatar setups -- all through standard AT Protocol records.
Models support GLTF, VRM, and external URIs. Metadata includes poly counts, bounding boxes, skeleton types for animation retargeting, and material info. Build a community asset library without needing to run your own hosting platform.
Earn an achievement in one game and carry the proof to every other. Achievement records include categories, tiers, progress tracking, and a server signature so other apps can verify you actually earned it.
A speedrunning badge from one world shows up in another. A social app can display your collection as a trophy case. Achievements are player-owned data, not locked in a platform's database -- they travel with you.
Your social connections shouldn't vanish when you switch platforms. Social records track friendships, guild memberships, reputation scores, and relationship types across games and virtual worlds.
Join a guild in one game and your membership shows up in the next. Block someone once and it carries everywhere. Your social graph is yours -- not scattered across a dozen isolated friend lists.
A generic 3D foundation for any app, plus an MMO layer for games that want stats, gear, and progression.
app.at3d.model 3D assets -- GLTF, VRM, or external URIapp.at3d.avatar Portable avatars -- parametric, GLTF, or VRMapp.at3d.scene Environments with objects, lights, and physicsapp.at3d.mmo.character Character profileapp.at3d.mmo.stats RPG stats and skillsapp.at3d.mmo.equipment Gear and cosmeticsapp.at3d.mmo.inventory Items and hotbarapp.at3d.mmo.world Server discoveryapp.at3d.mmo.validation Data attestationEvery record type in the at3d.app namespace. Use the core layer alone, or go all-in with MMO support.
3D asset record. GLTF, VRM, or external URI with metadata, thumbnails, and licensing.
corePortable appearance. Parametric palettes for 2D, custom GLTF models, or VRM for VTubers and social VR.
core3D environment with placed objects, lights, skybox, physics, and spawn points.
coreRoot identity linking avatar, stats, equipment, and inventory. Tracks level and currency.
mmoHealth, mana, stamina. Base attributes, skills with cooldowns, and passive effects.
mmoSlot-based loadouts with cosmetic definitions built from geometric primitives.
mmoItem collection with abstract effects and a quick-use hotbar.
mmoCross-game achievements with categories, tiers, progress, and server signatures.
mmoFriend lists, guild memberships, reputation scores across games and worlds.
mmoServer and room discovery. Connection info, player counts, and visibility modes.
mmoServer attestation of player data. Verdicts, strictness levels, and expiration.
mmoThree steps from your data server to any virtual world.
Create avatar and character records in your Personal Data Server. Upload a VRM, define a parametric look, or describe a scene. It lives where you control it.
VTuber tools, social VR platforms, and games resolve your AT URI references. They pull your avatar blob, read your stats, and render your identity using their own engine.
App servers publish validation records to vouch for your data. Other apps check those records to decide what to accept. No central authority -- just open, federated trust.
at3d.app is still taking shape. If you work on VTuber tools, social VR, avatar systems, indie games, or anything that touches 3D identity on the open web -- we'd love to hear what you think.
Drop your email to hear about spec updates, new tools, and when the character creator launches. We'll send a quick confirmation link.