[Nashooo]

IMO this is clearly implicit in the "you are a grandmaster chess player" prompt. As that should make generating best possible move tokens more likely.

[Ferret7446]

Is it? What if the AI is better than a grandmaster chess player and is generating the most likely next move that a grandmaster chess player might make and not the most likely move to win, which may be different?

[lukan]

Depends on the training data I think. If the data divides in games by top chess engines - and human players, then yes, it might make a difference to tell it, to play like a grandmaster of chess vs. to play like the top chess engine.

[cma]

Grandmasters usually play grandmasters of similar ELO, so it might think it doesn't always win. Even if it should recognize the player isn't a grandmaster, it still may be better to include that, though who knows without testing.