Smoke Teller

• WWizards of the Coast2014-09-20
  Official Ruling
  You could target a creature you control with Smoke Teller’s ability, but there’s no benefit to doing so. Remember, you may look at face-down spells you control on the stack and face-down permanents you control at any time.
• WWizards of the Coast2014-09-20
  Official Ruling
  Smoke Teller’s ability lets you look at the creature as the ability resolves. It doesn’t let you look at it later, although you should be given a reasonable amount of time to look at it. In a multiplayer game, be sure not to reveal the card to other players.

Rulings via Scryfall