View Notification Rule: Database Availability and Critical States

Hi,
where are placed into OEM 12c the Notification Rules functions 

Database Availability and Critical States (status up,down , metric error tetected ..)

Listener Availability (status up,down )

Agents Unreachable ( status yes , agent unreachable resolved ..)

to used for my target . is there a documentation ?

This is used to summarizes how and when Enterprise Manager will send notifications for this rule with a customised method (for example a procedure)

many thanks

Giorgio