What do appleeventsd and AppleIDAuthAgent do? I looked in the activity monitor to clarify what are those processes and started with alphabetic order. I know different resources where many processes are described. But appleeventsd and AppleIDAuthAgent are not the case even for goole search - only issues results were found without explaining what does these processes stands for.
appleeventsd is the Apple Events daemon, which handles cross-application interaction. It is the underlying basis for AppleScript amongst many other things.

AppleIDAuthAgent is "used to check the validity of AppleID certificates".