From the Scripting Manual
function OnCommand(ID: Byte; Text: string): boolean; Parameter Info: ID (Byte): ID of the player who sent the command. (255 = Server) Text (String): Command which has been sent. Description: This procedure will be called every time an ingame Admin or TCP Admin send a / command. You may add your own commands here.
begin if Text = '/test' then begin WriteLn('Test successful!'); end; Result := false; // Return true if you want to ignore the command typed. end;