If you call some ACSUtils function incorrectly, it will trigger an ACSUtils error.

ACSUtils errors instantly display an error message. All error messages begin with current game time in tics (Timer) and “ACSUtils error:”. The error message is displayed differently based on whether the error occured in singleplayer, clientside or serverside:

• In singleplayer, the error is printed using PrintBold.
• Clientside, the error is printed using PrintBold on the client. A “[clientside]” tag is prepended to the message.
• Serverside, the error is logged to server console using Log. A “[serverside]” tag is prepended to the message.

The PrintBold part can be disabled by setting the acsutils_noerror cvar to true, leaving only logging to server console.

• Calling a function with incorrect arguments
• Calling a clientside-only function serverside (for example, IsOpenGL())
• Calling a serverside-only function clientside
• Storing too many entries in fixed-size ACSUtils arrays (for example, HudPushState()). These static limits can be increased by editing acsutils.acs.