The phrase "plays close to the vest" means to be secretive, cautious, or guarded in one's actions or words. Antonyms for this expression would be open, transparent, communicative, frank, and uninhibited. An open person is one who shares their thoughts, feelings and intentions freely, without hiding anything. A transparent person is someone who is honest and sincere in all their dealings, and leaves nothing to speculation. A communicative person freely shares information and is open to feedback, while a frank person is upfront and honest in their opinions. Lastly, an uninhibited person is someone who is not restricted by conventions or societal norms and is open to exploring new possibilities. In essence, these antonyms emphasize the importance of being honest, transparent, and uninhibited in one's actions and words.