Inconsistent hand side and 3d keypoint annotation

[AlextheEngineer]

Hi,
Firstly, I'm trying to understand the hand side information. At first I thought the 'pts2d_2hand' or 'pts_w_2hand' parameter contains the left hand for one half and the right hand for the other half. But in the file I attached named "inconsistent_hand_side.zip", we have two right hands but the 2d coordinates are in different halfs. For two right hands, the 'hand type' parameter shows [0, 1] and [1, 0] and the 'hand_type_valid' parameter both shows [1, 1]. In addition, sometimes the 2d coordinates show strange values (e.g. [2.0, -0.67] for the sample in "unknown_2d_keypoints.zip").
Secondly, I'm trying to understand the annotated 3d keypoints. It's not always available and for instances that contain this data, the 3d keypoints data doesn't seem to be zero-centered and normalized (canonical) or in the world coordinate system (global). What determines if an instance has 3d keypoints and how should I interpret this data?
inconsistent_hand_side.zip
unknown_2d_keypoints.zip