# Fable 5.1 World Modeling > Source: > Published: 2026-09-02 19:49:01+00:00 **Worlds via code.** Explorable, browser-native reconstructions of real places — researched, modelled, and quality-checked end to end by autonomous [Claude Fable 5.1](https://www.anthropic.com/claude/fable) agent swarms, then shipped as plain [Three.js](https://threejs.org) apps you can run with `npm run dev` . No game engine. No proprietary 3D tiles. Every building, storefront, sign, tree and traffic light is generated from open data and public reference imagery by code that lives in this repo. ▶ Watch the full 59-second walkthrough · 1920×1080 · aerial, plaza, Nintendo, lower level, Apple The square and its surrounding blocks — Powell, Geary, Post and Stockton — on real terrain and a real street grid, with 129 identified storefronts, working traffic lights and cable cars, day/sunset/night, and two explorable interiors: **Apple Union Square** (300 Post St) and **Nintendo SAN FRANCISCO** (331 Powell St). Run it | `cd union-square-sf && npm install && npm run dev` | Buildings | 453 OSM footprints · 75 hand-authored façades · 129 named storefronts | Life | 220 pedestrians on a 1,398-node nav graph · 109 vehicles incl. Powell St cable cars | Interiors | Apple + Nintendo, 23 interactive objects | Validation | 34 camera-matched viewpoints vs. real photographs · 147 comparison sheets · 9 independent reviewer reports | More worlds coming. Each world follows the same pipeline, and every stage is in the repo so you can re-run it: **Reconnaissance**— parallel research agents pull OpenStreetMap geometry, USGS elevation, transit and street specs, and a storefront census with per-fact sources and confidence levels.**Offline asset generation**— Blender-as-a-library (`bpy` ) scripts emit optimised GLB kits: façade modules, street furniture, vehicles, vegetation, retail fixtures, pedestrian body parts.**Runtime**— a pure Three.js app assembles terrain, streets, façades, props, crowds and traffic from JSON specs.** Camera-match QA**— Playwright drives the real app, screenshots fixed viewpoints, and diffs them against free-licensed photographs taken from the same spot; independent reviewer agents (architect, geographer, technical artist, interaction) file reports that drive the next fix cycle. Code and generated assets: [MIT](/PhiloLabs/fable51-worlds/blob/main/LICENSE). Geometry is derived from [OpenStreetMap](https://www.openstreetmap.org/copyright) (ODbL) and USGS 3DEP (public domain). Reference photographs are not redistributed here — their provenance is recorded per sector in each world's `refs/*/SOURCES.md` . Brand names and logos identify the real businesses at their real locations and belong to their owners.