The attachment reminder looks for the word attachment (and other words like file types) in the body of your message and reminds you to add an attachment before hitting send.
Anagraw n ulɣu ad yesleḍ akken ad inadi awalen am amedday, isemli, afaylu (neɣ ismawen n isiɣzaf n ifuyla) udiɣ ak-id-immekti ad tsedduḍ isemli ma yella tettuḍ.