[runeks]

Writing software for which a full spec is available before you begin — in this case the rules of chess — was an easy problem even before AI.

[esikich]

There's no chess spec, it's not "solved" like it's just a matter of implementation. Chess bot programming wouldn't be a thing otherwise. I think it's really quite funny that you think this super complicated game is just some trivial programming problem. Try it.

[oldsecondhand]

It's easy to make a chessbot that only makes valid moves. Making a chessbot that plays optimally is hard.

But OP wasn't talking about solving optimalization problems, but understanding the rules of a business domain.