Claim draws

[Fermin Serrano]

Last Chess-war tournament, my engine plays a few games where Tournament Director declare them as loss when they were technical draws.
My engine analyzes all positions and if there are insufficient material I declare a draw. Olliver told me that I can not declare draws, but I can claim them. My question is:
what draws must I claim and what draws can I sets as win or lose without continue playing?

[Harald Johnsen]

I think the draws you could claim are those from the fide rules and no other draws (like table base draws).

But there is no need to code anything about game continuation. You are supposed to play when you are asked to (by the ui/automated tournament manager).
The tournament manager will stop the game when needed (mate, draw, etc).

HJ.

[Pedro Castro]

Hi Fermin,

If there is a insufficient material on both sides, you can claim the game draw and immediately stop the engine. A insufficient material occurs when both sides have not pawns and the material is less than a rook, there are 3 exceptions: if each side has a knight, if one side has a knight and the other a bishop and finally if each side has bishop of a different color.

The other cases that you can claim draw are stalemate, triple repetition and 50 moves rule.

You can also stop the engine when do checkmate or when you receive, if is you who gives you send claim to the engine, regardless that the gui can do.

If you send a claim of won or draw when in fact it is not, then the director of the tournament normally punishes the engine and makes you lose the game.

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xboard protocal -->

RESULT {COMMENT}
When your engine detects that the game has ended by rule, your engine must output a line of the form "RESULT {comment}" (without the quotes), where RESULT is a PGN result code (1-0, 0-1, or 1/2-1/2), and comment is the reason. Here "by rule" means that the game is definitely over because of what happened on the board. In normal chess, this includes checkmate, stalemate, triple repetition, the 50 move rule, or insufficient material; it does not include loss on time or the like. Examples:
0-1 {Black mates}
1-0 {White mates}
1/2-1/2 {Draw by repetition}
1/2-1/2 {Stalemate}

[Jaco van Niekerk]

Isn't that bishops of the same colour being a draw?

Here is a technical mate with bishops of different coloured squares:

KBx
xxx
xkb

[H.G.Muller]

Indeed,KBKB with Bishops of like color is draw. This is implied by Pedro, as he did not mention it in his exceptions.

So WinBoard recognizes the following as draw-by-rule:
KK
KBK
KNK
KBKB (like B)
KBBK (like B)

These are the draws that can be claimed by the engine. Practical draws that are not draw by FIDE rules, (because checkmate positions are possible), and can thus not be claimed by an engine, are:

KNNK
KNKN
KBKN
KNKB
KBKB (unlike B)
KRKR

The engine will have to play on in such cases, or it will forfeit the game. The TD can decide to have WinBoard adjudicate such games as draws, so that the engines would not have to play on very long.