Pascal Editor is a browser-based 3D building editor for drawing floor plans and turning them into walls, rooms and furnished interiors you can share. It is aimed at people who want to lay out a real building without committing to a professional CAD package, and at developers who want a 3D architectural canvas they can embed or automate. The repository, published by pascalorg under an MIT license, holds the editor itself plus the packages it is built from, and it has collected about 22,800 stars and 2,900 forks since it first appeared in October 2025.
What it does
The short version is the one from the video: you draw a floor plan, and it becomes a room you can walk around. Walls are dragged into place, furniture is dropped in, and the scene renders as you work rather than after a batch step. Projects can be created and shared, which is what the repository's own one-line description promises.
Two things set it apart from a plain in-browser modeller:
- It is packaged for reuse. Three packages are published to npm —
@pascal-app/core,@pascal-app/viewerand@pascal-app/cli— so the model layer and the viewer are available to other applications, not only to the hosted editor. - It speaks MCP. The project ships an authenticated MCP service, which means an AI agent can be pointed at the editor and asked to build or modify a scene instead of a person clicking every wall into position.
How it works
The editor is a TypeScript web application. Its 3D layer is React Three Fiber, the React binding for Three.js, and it renders through WebGPU rather than the older WebGL path — so the browser you open it in needs to support WebGPU. The repository also tags itself for CAD, BIM and parametric design, which is a fair description of the kind of model it keeps: a building described by its parts, not a mesh you sculpt.
Running it locally is handled by the CLI. It starts the editor and the MCP service together in the background, picks loopback ports that do not collide with whatever else you have running, and keeps your projects in a local database file at ~/.pascal/data/pascal.db. Nothing needs to leave your machine for the editor to work. An agent is wired in by configuring it to launch pascal mcp connect.
Getting started
With Node.js 22.13 or newer you do not have to clone anything:
npx @pascal-app/cli editor
That creates a persistent local installation. The project's "Run Pascal locally" documentation page covers the rest — pnpm and Bun commands, managing projects, MCP setup, updates, storage paths and troubleshooting.
One wrinkle is worth knowing before you start. The npm beta tag currently resolves to @pascal-app/cli@1.0.0-beta.1, which is older than the repository and predates the read-only furniture candidate input added here. If you need that capability now, the README points at a verified GitHub prerelease built from a specific commit rather than at npm. For everything else, the npm release is the runtime the documentation describes.
When to use it / when not
It is a good fit when the goal is a spatial layout you can see and share: sketching how a floor divides up, trying furniture arrangements, or giving a client something to look at in a browser tab with no install. It is also a good fit if you are building software and want a 3D architectural view inside it — the separate viewer package exists for exactly that — or if you want an agent to generate scenes programmatically through MCP.
It is a weaker fit when you need what a full professional CAD or BIM suite gives you. The materials here describe an editor, a viewer and an agent interface; they make no claims about construction documentation, structural or energy analysis, or exchange formats for handing a model to an engineering team. The project is also young — first commit in late 2025, still actively pushed through September 2026 — and parts of it, like the candidate-input feature above, are ahead of the published releases. Treat it as a fast-moving tool rather than a settled one.
Anyone who has wanted to lay out a building and bounced off the learning curve of traditional CAD should try this, because the cost of trying is one npx command. Developers have a second reason: the core and viewer packages, the MIT license and the MCP service make it one of the few architectural editors you can genuinely build on top of, embed in your own product, or hand to an agent. If your work touches floor plans, interiors or 3D on the web, it is worth an afternoon.