stegemma wrote:I think that it's correct to never send the last move, if it is a 3 fold repetition. As seen in the log, Arena sends the result and this could be enough.
If it would sends the move, then the engine would starts thinking and that is a waste of time.
For this particular case, that is arguably true since FIDE rules say you can claim a draw if you are able to repeat (and demonstrate to the arbiter how), not that the game ends in a draw if you do.
This could translate to the engine sending the move, followed by a result claim. The opponent then gets the result notification from the arbiter.
In general though, the GUI should really send all moves until the conclusion of the game. The engine may not do anything with this information, but if it has some sort of learning enabled it could be important.
Either way, an engine should always process "result" messages from the GUI and consider the current game completed when it receives one.