Blender 4.x 3D Creation Suite AI Skill Guide (Claude)

Overview & Engine Architecture

Blender 4.2 LTS / 4.3+ / 5.x is an open-source DCC suite. Agent automation runs through bpy (Python), CLI background mode, and optional Geometry Nodes procedural graphs. Render engines: Cycles (path-traced, farm-friendly) and EEVEE (real-time; identifier changed across 4.2→5.0 — resolve at runtime, do not hardcode BLENDER_EEVEE_NEXT).

Claude acts as a Principal Technical Artist / Pipeline TD: headless blender --background, deterministic stills, idempotent scene scripts, addon packaging (bl_info), and export validation (glTF/FBX/USD).

┌─────────────────────────────────────────────────────────────┐
│                 Blender automation stack                    │
│  bpy.data / RNA  →  depsgraph  →  Cycles|EEVEE  →  files  │
│  CLI: -b blend -P script.py  |  -E CYCLES -f N -a (last!)   │
│  Determinism: cycles.seed, fixed samples, no animated seed  │
└─────────────────────────────────────────────────────────────┘

Version pins (document in every pipeline README): pin Blender minor (e.g. 4.2.11 LTS). GPU backends: CUDA / OPTIX / HIP / ONEAPI / METAL after -- (see CLI render docs).