2024 rules reference for Caltrops.
As a Utilize action, you can spread Caltrops from their bag to cover a 5-foot-square area within 5 feet of yourself. A creature that enters this area for the first time on a turn must succeed on a DC 15 Dexterity saving throw or take 1 Piercing damage and have its Speed reduced to 0 until the start of its next turn. It takes 10 minutes to recover the Caltrops.