Can one write scripts to send alert messages to the console?

Start the OEM console and create a new event. Select option "Enable Unsolicited
Event". Select test "Unsolicited Event". When entering the parameters, enter
values similar to these:

Event Name:	/oracle/script/myalert
Object:		*
Severity:	*
 Message:	*

One can now write the script and invoke the oemevent command to send alerts to
the console. Look at this example:

oemevent /oracle/script/myalert DESTINATION alert "My custom error message"

where DESTINATION is the same value as entered in the "Monitored Destinations"
field when you've registered the event in the OEM Console.