Pascal Editor

// Overview

Pascal Editor is an open-source, local-first 3D building editor built with React Three Fiber and a WebGPU Three.js renderer. It runs in the browser or from a CLI, and it exposes the scene to AI coding agents through a Model Context Protocol server, so an agent can inspect and edit a building model using the same operations a human would perform in the UI.

The scene is described by typed nodes rather than a mesh soup. Every node extends a `BaseNode` carrying an id, a type discriminator, a `parentId`, visibility and optional camera and metadata, and the architectural hierarchy runs Site → Building → Level → Wall, Slab, Ceiling, Roof, Zone, Scan and Guide, with doors, windows and lights attached as items. Nodes live in a flat dictionary keyed by id, with parent-child links expressed through `parentId` and `children` arrays, and scene state is held in a Zustand store with Zod schema validation, Zundo undo/redo and three-bvh-csg for boolean geometry.

Running the CLI starts both the editor and an authenticated MCP service on collision-free loopback ports, keeping projects in `~/.pascal/data/pascal.db`. The local connector needs no Pascal account or API key and does not upload projects on its own. The repository also publishes agent skills — `pascal-3d` for MCP setup and verified scene work, and `furniture-fit` for bounded footprint assessments — installable through skills.sh or as a Claude Code or Codex plugin. Pascal asks that you use one active agent client per local CLI service, since the standalone local HTTP runtime shares scene state between clients.

// What it does

• Local-first 3D building editor on React Three Fiber with a WebGPU Three.js renderer, usable in the browser or from the CLI
• Authenticated MCP service started alongside the editor so agents can read and edit scenes; `pascal mcp connect` runs without the editor process
• Typed architectural node hierarchy — Site, Building, Level, Wall, Slab, Ceiling, Roof, Zone, Scan and Guide — stored in a flat id-keyed dictionary
• Zustand scene store with Zod validation, Zundo undo/redo and three-bvh-csg boolean geometry operations
• Publishable agent skills (`pascal-3d`, `furniture-fit`) installable via skills.sh or as a Claude Code or Codex plugin
• Embeddable packages — `@pascal-app/core`, `@pascal-app/viewer`, `@pascal-app/editor` and `@pascal-app/nodes` — for mounting the viewer in your own React app

// Getting started

Node.js 22.13 or newer can create a persistent local install without cloning the repository. The npm package holds the CLI and the MCP service; the web editor runtime is downloaded once per version and verified against a digest published inside the package.

npx @pascal-app/cli editor

npm install --global @pascal-app/cli

npx skills add pascalorg/editor \
  --skill pascal-3d \
  --skill furniture-fit

/plugin marketplace add pascalorg/editor
/plugin install pascal-agent-skills@pascal

npm install @pascal-app/core @pascal-app/viewer @pascal-app/editor @pascal-app/nodes

bun install
bun dev

Commands and code are distilled from the project's own documentation — always check the official repo for the latest.

// When to use it

• Let a coding agent lay out or revise a building model through MCP instead of hand-editing geometry files
• Sketch floor plans, walls, slabs and roofs locally without uploading a project to a hosted service
• Check whether furniture fits a space using the repository's bounded, evidence-based `furniture-fit` skill
• Embed an interactive 3D building viewer in a React application using the published Pascal packages

// How Pascal Editor compares

Pascal Editor alongside other open-source 3d & cad generation tools AI/TLDR tracks, ranked by GitHub stars.