Hello. I am not sure what kind of "specs" you would need regarding a slipping belt or bad bearing.
Generally if the belt is slipping it needs to be replaced. If a bearing is bad it needs to be replaced.
1. Remove the water pump belt, and with it off, start the engine. Does it squeak now? Yes = its not the water pump or belt No = go to 2
Note: check water pump for smooth rotation and no lateral play (with engine off) 2. Replace water pump belt. Does it still "screech"? Yes = replace water pump No = Repair complete, enjoy adult beverage.