An entity refers to an action that you are trying to perform. For example, when trying to convert a track, the entity in this case would be track.
The entities currently supported are:
Track
Playlist
When you convert a playlist, you have to pass a target_platform body and specify the platform you want the result fetched for and response you get is a task id.
It is important to note that unlike playlist conversion, track conversion returns the result immediately and you are not polling a task id.
The platforms supported for track entities are
Apple Music
Spotify
Deezer
TIDAL
Youtube Music
The Platforms currently supported for playlists entites are
Apple Music
Spotify
Deezer
TIDAL
Playlist results may return incomplete number of results for the target platform.
When you convert a playlist and a platform result does not match the number of results in the source platform, you get the omitted tracks as part of the results.