alert vs open-eyed

alert is a noun but open-eyed is not a noun.

Word	Noun	Adjective	Verb	Adverb
alert	Yes	Yes	Yes	No
open-eyed	No	Yes	No	No

alert (noun)	open-eyed (noun)
a warning serves to make you more alert to danger
an automatic signal (usually a sound) warning of danger
condition of heightened watchfulness or preparation for action

alert (adjective)	open-eyed (adjective)
engaged in or accustomed to close observation	carefully observant or attentive; on the lookout for possible danger
mentally perceptive and responsive
quick and energetic

alert (verb)	open-eyed (verb)
warn or arouse to a sense of danger or call to a state of preparedness