void HandJoint(Vec3 position, Quat orientation, float radius)

You can make a hand joint of your own here, but most likely you’d rather fetch one from Input.Hand().Get()!

Vec3 position The center of the joint’s world space location.
Quat orientation The joint’s world space orientation, where Forward points to the next joint down the finger, and Up will point towards the back of the hand. On the left hand, Right will point towards the thumb, and on the right hand, Right will point away from the thumb.
float radius The distance, in meters, to the surface of the hand from this joint.

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