tl;dr: Fable 5.1 uses autonomous Claude agent swarms to generate explorable browser-based 3D reconstructions of real places (currently San Francisco's Union Square and Kyoto's Higashiyama district), shipped as plain Three.js apps with no game engine or proprietary tiles. Buildings, storefronts, crowds, and interiors are generated from OpenStreetMap, USGS elevation data, and public imagery via a pipeline of research agents, Blender scripts, and Playwright-driven camera-match QA against real photographs. The Kyoto survey notably overturned six commonly-cited measurements for landmarks like the Yasaka Pagoda and Kiyomizu-dera stage.