Ah, of course. That makes good sense -- sorry for the bother. However, I have two follow-ups.
The fact that the last indented line under "plays a Library" often is "discards <action-card(s)>" is a tad confusing. That is, in most cases it makes sense, in that the AI is choosing not to play the discarded card(s), but I cannot always account for the number of cards in the AI's hand -- in most of the cases where the numbers don't add up, I assume that the missing cards are victory point cards...which is fine but why aren't these noted in an analogous "discard" message?
And, there's still one case that I don't understand -- Turn 13: assuming that Revenge Witch starts with three cards and plays the Library, draws seven (total) cards, sets aside two (total), and discards two, she should have five cards left (3-1+7-2-2), and yet she somehow plays 2 each of coppers, silver, and gold, for a total of six! What am I missing?
(By the way, I think that this implementation of Dominion is beautiful and nicely playable, and I've learned a lot from the AI's play!)
Given that each player's deck starts with seven coppers and three estates, upon seeing the first turn's hand a human (should) know what the second turn's hand is going to be. However, it's evident that the AI wasn't endowed with this ability.
For instance, if the AI is dealt five coppers on the first turn, it will buy a Chapel if one is available; and then, on the second turn, it will buy nothing. A human in that position would have deferred the purchase of the Chapel to the second turn and taken advantage of the chance to buy something else like a Library or Council Room.