This might be your idea of a semicircular sandy strip backed by sea grapes and tropical shrubs, gentle aquamarine surf, a coral reef close to shore, plus some rocks and seaweed for rewarding snorkeling and a view out to some huge pierced rocks (roches perc??es) that partly shelter the entrance to the cove.
This might fit the description you are looking for, a gentle surf, coral reef within swimming distance to shore, and rocks and seaweed for snorkling.