PhiloLabs Ships Agent-Built 3D Union Square and Kyoto Worlds

Fable51-worlds, an open GitHub repository from PhiloLabs, ships two browser-native 3D reconstructions built end-to-end by autonomous Claude Fable 5.1 agent swarms: Union Square in San Francisco and the Higashiyama route in Kyoto. The README frames it simply: "Worlds via code. Explorable, browser-native reconstructions of real places."

The San Francisco world stitches 453 OpenStreetMap building footprints along Powell, Geary, Post and Stockton into a walkable block with 75 hand-authored façades, 129 named storefronts, 220 pedestrians on a 1,398-node navigation graph, and 109 vehicles including Powell Street cable cars. Two interiors, Apple Union Square at 300 Post St and Nintendo SAN FRANCISCO at 331 Powell St, are enterable and carry 23 interactive objects between them. Validation ran to 34 camera-matched viewpoints against real photographs, 147 comparison sheets, and 9 independent reviewer reports.

The Kyoto build is longer: a 2.3 km continuously walkable path from Gion through the Yasaka Shrine, Ninenzaka and Sannenzaka up to Kiyomizu-dera, climbing 76 meters over 266 buildings, 471 shopfronts, 1,938 trees across 11 species, and 3,076 props of 60 kinds. The style is deliberately non-photorealistic; the README calls it "hand-painted anime background," rendered with cel materials, screen-space ink pulled from depth differentials, and split-tone grading, with no binary 3D assets in the repo.

Buried in the Kyoto notes is a QA result that arguably justifies the exercise. The agents' survey concluded that the Yasaka Pagoda is 38.79 m (not 46 m), that the Kiyomizu stage deck sits at 115.5 m above sea level rather than 240 m, and that the stage itself measures 21.8 × 9.6 m on 168 pillars of 0.64 m diameter. Geometry is derived from OpenStreetMap under ODbL, USGS 3DEP elevation data in the public domain, and GSI 1 m LiDAR queries for the Kyoto terrain; code and generated assets are MIT.

It lands amid a steady drumbeat of agent releases (three others showed up in our agents feed the same day, one of 405 we've tracked in 90 days, alongside code-scale efforts like BAAI's DisCo distilling 1,000 repos into reusable skills), but is unusual in what the swarm is asked to produce: a walkable artifact a human can camera-match against photos and challenge on measured dimensions, rather than a benchmark score.