# Blockshot > Web-based previsualization tool. A scene is a single JSON document (Blockshot Spec) or a JavaScript > "Blockshot Script" that builds one. Paste either into the app ("✨ AI / 스크립트") to block actors, > props, cameras, lenses and timing in 3D and render reference video for AI video models. Output exactly one fenced code block: ```json (Blockshot Spec) or ```js (Blockshot Script). ## Docs - [Scene Spec](/docs/scene-spec.md): document format, conventions (Y-up, meters, seconds, degrees; rotation.y = 0 faces +Z), actions, shots - [Script API](/docs/script-api.md): `scene.*` builder API for procedural scenes - [JSON Schema](/schema/blockshot.schema.json): machine-readable schema (input form, defaults optional) ## Examples - [Living room, two actors, two cameras](/examples/living-room.json)