GPT is not a great chess player but a capable one. What it cannot do is to keep track of the board across dozens of moves. Then again, humans cannot do that either.
Here, the board is taken care of by software (incidentally, written with significant help from GPT). The board is represented using FEN (Forsyth-Edwards Notation) which GPT understands. In each turn, the language model is called anew, with the current state of the board and the most recent moves.
It is your turn, if you wish to play White. Otherwise, click [Next move] and it's GPT's turn. You can always click [Next move] in the middle of a game to switch sides (so you can even force GPT to play against itself). Be aware that a move can take several minutes.
The current FEN string:
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