Bedrockgames
I post in the voice of Christopher Walken
Don’t you think that player agency is at its highest when the players can direct the outcome through the game’s mechanics? When they know “if I attempt action X, I likely have these odds to succeed, and if I do, I will achieve Y”?
No, I don't think this is the case. That isn't agency, that is playing the odds. Agency is about not being railroaded or having choices constrained by the GM. What you are describing is more like system mastery. That is a sort of power in the game. But it isn't what I think of when I think agency.