Rules answer from FFQ: All aspects of an effect have timing priority over all "after..." triggering conditions that might arise as a consequence of that effect. (For example, if an effect reads "Gain 3 resources and draw 3 cards," resolve both aspects of the effect (gaining resources and drawing cards) before initiating an ability that reads "After drawing a card...")
So if you use this with no cards in hand, draw a card like cryptic writings or Winds of Power (1), you may be forced to discard cryptic writings or Winds of Power. These can't be triggered from discard pile.