base_humanoid rig

A reference humanoid skeleton: one bone per humanoid role (hips, spine, leftarm, righthand, leftupleg, …), each bone named after its role, in a neutral T-pose.

The humanoid avatar type reads which bone fills which role from the skeleton's structure, as it does for every rig: rig:qualify() on this asset maps each bone onto the role it is named after. rig.json is readable on purpose: open it to see every bone, its parent and its T-pose offset.