ArticulateCode: Functional Contracts and Physical Baking for Articulated 3D Asset Generation

Training embodied agents at scale calls for varied furniture and appliances that can be opened, grasped, and used for storage in simulation. Generating their appearance and joint motion is only part of the task: a drawer pull must belong to the drawer, and its collision shapes must leave room for an object inside. We present ArticulateCode, which turns a reference image and an interaction request into executable programs for named parts and a physically compiled articulated asset. A functional contract specifies moving parts, joints, handle ownership, and usable interiors. It guides part construction and remains attached to the rigid bodies and collision shapes produced by physical baking. When collision shapes are rebuilt on identical generated meshes, component-aware shapes clear every sampled joint sweep and all loaded-motion cycles, whereas per-body convex decomposition introduces 3.08–18.13 mm of interference. A geometry-level audit localizes three misplaced repeated parts in two generated assets, and a single part-level code revision repairs each. ArticulateCodeBench, our companion evaluation protocol, compares final assets from direct generators, feedback agents, and full systems under shared interaction requests.