Charm of Goldfinches

You release a small flock of 10 Goldfinches attempting to charm up to three creatures you can see within range. Each creature must make a Wisdom saving throw, and do so with advantage if you or your companions are fighting it. If it fails the saving throw, it is charmed by you until the spell ends or until you or your companions do anything harmful to it. The charmed creatures regard you as a friendly acquaintance. When the spell ends, the creature knows it was charmed by you.