Rule 422.1

Discarding a card is moving it from a player's hand directly into their trash without activating or executing its normal rules text.

• 422.1.a The player who is performing the action chooses which cards to send to their Trash, and may use Private Information to…
• 422.1.b “When I am discarded” abilities or other Triggered Abilities that trigger on discarding are executed after discarding…

Official Core Rules