@minecraft/creator-tools/data/content/newitemjson/render_controller.json

Minecraft Creator Tools command line and libraries.

{
  "format_version": "1.8.0",
  "render_controllers": {
    "controller.render.targetname": {
      "geometry": "Geometry.default",
      "materials": [{ "*": "Material.body" }, { "head": "Material.head" }],
      "textures": ["Texture.default"]
    }
  }
}