The Item API for WoW Classic (TBC) is currently missing informations about item sockets as well as about the spell haste stat.
A good example for this is the “Sunfire Robe” (34364) which has 3 red sockets, a socket bonus and “Equip: Improves spell haste rating by 40”.
All of this information are missing in the item API response.
The item API is also lacking information about the phase the item was/ will be released in. Since TBC is released in phases, that information would help allot.
I hope this information is usefull and that the API is extended soon