
3D AR Studio
io.github.nirholasPublished by GitHub account nirholasv0.3.0Updated Oct 24, 2026
Put 3D models in someone's real room: generate, arrange, and hand back one AR link.
Overview
A local MCP server that lets an assistant generate 3D models, search a model library, arrange AR scenes and return a single link that opens them in a real room.
- What you can do
- Generate 3D models from text prompts and collect generations still rendering when the first call returns, with links that open the result in AR. Search a free CC0 model library, or a catalogue you configure, by name, category and tag. Arrange several models into one scene and get a single link that reopens it exactly. Turn any GLB URL into a device-aware AR viewing link, or emit a self-contained HTML page embedding the studio.
- When to use it
- Useful when someone wants an assistant to build an augmented-reality scene from a description and hand back a link a phone can open in the real room, or to produce a ready-to-commit AR page.
- Requirements
- Runs locally via npx, so Node.js is needed. No API key or account is required. Optional environment variables AR_STUDIO_ASSETS, AR_STUDIO_MCP_ENDPOINT, AR_STUDIO_ORIGIN and AR_STUDIO_PAGE_URL point it at your own catalogue, generation endpoint, origin and page. Network access is needed for model generation, search and hosted AR links.
Installation
In SourceWeft
- Open 3D AR Studio in the dashboard and add it to a workspace.
- Enable the server for the chats that should use its tools.
Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.
Other MCP clients
Follow the launch instructions in the repository.
README
3D AR Studio
[GitHub stars] [License] [Last commit] [PRs welcome] [AI agent friendly]
Drop a full augmented-reality studio into any web page.
Place as many 3D models as you like in your real room through the camera, describe a new one and watch it appear, arrange everything by hand, then share the whole scene as a link, a QR code, or a live room someone else can build in with you.
Live demo · npm · MCP server
That is a working AR studio. No build step, no API key, no account. It comes wired to a free library of a few hundred public-domain models and a free, keyless text-to-3D lane; point it at your own catalogue with one option when you are ready.
Why this exists
Every web-AR drop-in places exactly one model and then hands off to a native viewer, which ends the session. This one keeps the whole scene in your page:
- Many models, one room. Place, drag, pinch-resize, twist-rotate and duplicate as many models as you want in a single live camera view.
- Generate without leaving the camera. Type "a brass desk lamp" into the dock. The generation runs behind the live view and the finished model drops into the room.
- Real WebXR where it exists. An always-armed hit-test reticle, one
XRAnchorper placed model, real-world light estimation, and depth occlusion so models hide behind your furniture. - Real ARKit and ARCore everywhere else. iPhones have no WebXR, so tapping Place in your
space opens Apple's AR Quick Look for real: true plane detection, true scale, true
occlusion, the system's own "View in AR" sheet. The model is converted to USDZ on the device
(a real conversion via three.js's
USDZExporter, no server involved) and, because it is exported from the copy already standing in your scene, it arrives at the size you pinched it to and in the pose it was in, stood on the floor rather than hanging at the height it happened to be modelled at. Android without WebXR gets Scene Viewer. Desktop gets a grid preview and a QR hand-off to a phone. - Scenes are links. Models, positions, rotations and scales round-trip through the URL. Compose on a laptop, scan the QR, it reopens exactly on your phone.
- Build together, live. Open a room, share a six-character code, and every add and move syncs to everyone in it.
- Characters actually move. Any humanoid GLB with no baked animation gets an idle clip retargeted onto its own skeleton. No rig allow-list, no T-poses.
- Agents can drive it. A bundled MCP server lets Claude, ChatGPT or your own agent generate a model, compose an arrangement, and hand a person one link that opens it in their room.
The rendering ladder, anchor lifecycle, retargeting pipeline, scene format and shared-room protocol are extracted from the AR surfaces running in production on three.ws, and generalized so they work on your site with your models.
Install
three is a peer dependency, so you keep one copy of it and pick the version. The CDN bundle
(dist/ar-studio.min.js) has three.js inside it and needs nothing else.
The studio fills its host element absolutely, so give the host a height (any positioned box
with a real height works; a <div> with no height gets a sensible 70vh default rather than
rendering invisibly).
Scaffold a deployable page
deploy prints every git and gh command before it runs it. It needs
git and the GitHub CLI; without them it tells
you the three manual steps instead of failing silently.
Templates: static (one HTML file, no build), vite, react.
Both 3d-ar-studio and ar-studio run the CLI. The MCP server is a separate
binary in its own package, so npx 3d-ar-studio-mcp resolves cleanly: see
MCP server.
Your own models
The tray is filled from three.ws by default: a few hundred public-domain (CC0) props, free for
commercial use, served with open CORS. Swap in your own with the assets option.
A JSON file anywhere. Five common shapes are read without reshaping:
Per entry, the model URL is read from the first present of src, url, glb, glb_url,
glbUrl, file or model; the label from title, label, name or prompt; and the
thumbnail from poster, thumb, thumbnail, image or preview_image_url. Anything that
is not an https (or site-relative) URL is dropped rather than handed to the loader.
A list you hold in code:
Several tabs at once, in the order you want them:
Built-in keys: 'three.ws' (the default set), 'recent', 'objects', 'community', 'link'.
Anything else. A source is an object with a list():
Throwing from list() is fine: the tray renders a designed error state with a Retry button.
Your users can retarget it too, without touching your code: ?assets=https://…/manifest.json
on the page URL. Only https URLs are accepted, and every model source is re-validated before it
reaches the loader, so a hostile link can add a catalogue but can never smuggle a
javascript: or data: model into the scene. Set allowUrlOverride: false to switch that off.
CORS
Models are loaded by the browser, so the host serving your .glb files has to allow
cross-origin requests (access-control-allow-origin). If a model fails to load, that is
almost always why, and the studio says so in the status line rather than failing silently.
Options
URL parameters
Methods
Events
studio.on(name, fn) returns an unsubscribe function. The same events also fire as
ar-studio:<name> DOM events on the mounted element.
Web component
element.studio is the live instance. Importing 3d-ar-studio/auto (what the CDN bundle
does) registers the element for you.
Keyboard and accessibility
Every control is a real button with an accessible name, the source tabs implement the full ARIA tablist contract, and each dialog takes and returns focus.
prefers-reduced-motion removes the spawn-in animation and every transition.
MCP server
No API key. Every tool is free and keyless.
A session looks like this:
Device support
The AR button in the top bar always takes the best path the device has, labels itself so it never promises the wrong one, and acts on the selected model (or the last one placed).
Camera and WebXR both need a secure context: https:// or localhost.
Placing one model in someone's real room
On a device with WebXR the AR button goes straight into an immersive session. Everywhere else it opens the hand-off sheet: which model is going, a picker when the scene holds more than one, and a single primary button that opens the device's own AR viewer.
The sheet exists for one specific reason, and it is worth knowing about if you are building your own UI on top of this package:
iOS opens AR Quick Look only while the page still holds the user gesture that asked for it. Converting a GLB to USDZ takes a second or two. Start the conversion inside the tap handler and by the time the
<a rel="ar">is clicked the gesture has expired, Safari silently declines, and the button looks broken. That is the single most common reason a "View in AR" button does nothing on an iPhone.
There is a second trap right behind it, and it is worse because the failure looks like success:
Safari decides whether a URL is an AR asset from its file extension. A
blob:URL has no path, so it has no extension. Hand one to<a rel="ar">with no filename and Safari still opens Quick Look, but as a generic 3D preview: the viewer comes up in Object mode with AR unavailable. Settingdownload="something.usdz"on the anchor gives Safari the name it sniffs, and Quick Look enters AR.openQuickLook()does this for you.
So the package splits preparing from opening, and never does them in one tap:
prepareNativeAr resolves to null on a device with no native AR viewer, { viewer: 'quicklook' } on iOS with a blob: USDZ ready to open, and { viewer: 'sceneviewer' } on
Android, where nothing needs converting at all. Conversions are cached (four at a time,
least-recently-used, object URLs revoked on eviction); isQuickLookReady(key),
releaseQuickLook(key) and clearQuickLookCache() let you drive that cache yourself.
The studio warms the cache in the background for whichever model the button would send, which
is why the second tap of the day is instant. placeInYourSpace() still exists and still does
both halves in one call: reach for it when the USDZ is already cached, or when you are calling
it from your own already-prepared button.
Exporting from the live scene rather than refetching the GLB is deliberate too: no second
download, no second CORS round trip, and the person gets the pose and the size they are
looking at. objectToUsdzBlob(object3D) is exported if you want that for your own three.js
scene.
Why a model hangs in the air instead of resting on your floor
The third trap, and the one that survives both of the others:
AR Quick Look anchors the scene's ORIGIN to the plane it detects, and never looks at the geometry. A GLB authored around its bounding-box centre arrives half-buried; one authored around a distant scene origin arrives floating across the room at whatever height it was modelled at. Both read as broken tracking, and no anchoring property fixes either: the content has to be moved.
Every export from this package is therefore stood on y = 0 with its footprint centred over
the origin before it is written. groundOnFloor() is exported if you want to do that to your
own scene.
Two smaller ones ride along with it:
USDZExporterwalksscene.childrenand writes each node's LOCAL matrix, so the transform on the object you hand it is never written at all. Set a scale on the root and the file comes out at the original size with no warning.usdzExportRoot()wraps content in an identity root plus aModelstage node, and every placement this package applies rides on the stage, which does get written.
USDZ is metres (
metersPerUnit = 1). A 75 cm prop authored in centimetres arrives 75 m tall, too large for any plane ARKit found indoors, and swims around the viewer. Pass{ fit: true }tosceneToUsdzBlob()(glbUrlToUsdzBlob()already does) to normalize a model straight off the network. Anything already within 2x of a believable real-world size is left exactly as authored.
And the one that looks most like broken tracking of all:
Quick Look does not place a model until ARKit has found a plane big enough to hold it. Until then it hangs aligned to the camera and travels with the phone. Past a certain size there is no such plane in an ordinary room, so it never lands at all. Every export is capped at
MAX_AR_FOOTPRINT_M(2.5 m) andMAX_AR_HEIGHT_M(2.5 m) byclampToPlaceableSize(). A ceiling, not a normalizer: furniture, people and props go through untouched.
The camera is one client at a time
The studio releases its getUserMedia passthrough on the way into the device's AR viewer and
restarts it when you come back. Leave the page's stream running and ARKit starts against a
camera another process is already holding: the model appears, and then world tracking and
plane detection never converge, so it drifts with the phone instead of settling. If you drive
the hand-off yourself from your own camera UI, stop your tracks before you call open().
Passthrough itself is a gyroscope over a video feed: it turns with you, and that is all. It has no plane detection and no positional tracking, so it will never hold a model to a spot on a real floor. On iOS that is what Quick Look is for, and the studio's status line says so.
Development
The published site is committed under docs/ and served by GitHub Pages from the main
branch. There is no CI workflow: npm run build && npm run build:site, commit, push.
Licence and credits
Apache-2.0.
The bundle includes three.js (MIT) and colyseus.js (MIT). The default model library is CC0 content from Poly Haven, and the default generation and animation lanes are hosted by three.ws. None of them is required: every one is a URL you can change.
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Built for AI agents too
Coding agents and LLM tooling can read this repo directly: AGENTS.md, llms.txt, llms-full.txt. Point an agent at https://github.com/nirholas/3D-AR-Studio and it has the context it needs.
More from the same author
- All repositories by nirholas: the full catalog, grouped by topic
- three.ws: the platform for 3D AI agents with Solana wallets, a skill marketplace and x402 payments
- Questions or ideas: open an issue or start a discussion
Contributors
Source: README.md at commit ff4c549
Tools
0Version history
1- v0.3.0LatestSep 16, 2026
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