You ward an area to alert you when creatures enter without your permission. When you cast
alarm, select a password. Whenever a Small or larger corporeal creature enters the spell's area without speaking the password,
alarm sends your choice of a mental alert (in which case the spell gains the
mental trait) or an audible alarm with the sound and volume of a hand bell (in which case the spell gains the
auditory trait). Either option automatically awakens you, and the bell allows each creature in the area to attempt a DC 15 Perception check to wake up. A creature aware of the
alarm must succeed at a
Stealth check against the spell's DC or trigger the spell when moving into the area.