The Courtesy of the Three Rings - AI-generated fantasy Puzzle

The Courtesy of the Three Rings

Along a glittering riverbank in the Feywild, a crescent of white stones frames a shallow basin that seems to drink moonlight instead of water. Reed-chimes sway though there is no wind, and every step near the bank makes the mud answer with a soft, delighted sigh. Three rings in the basin turn with a slick, musical click, and whenever one is set correctly the reeds brighten and a faint path of silver ripples across the shallows; when set wrong, the water flashes green and the nearby willows titter like onlookers at a private joke.