SGF Issue: very first move was AB instead of B

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When I downloaded the SGF of this game, Black very first move was AB[pc] instead of B[pc].

Based on what I read, AB is akin to placing handicap stones at coordinate [pc]. And this is not considered as Move #1 for KaTrain or Sabaki SGF editor.

The handicap property (HA) was not specified, so AB shouldn’t be used, correct? Or am I not understanding something here?

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Attempt to root cause, not saying it should be this way:

I think Handicap is set to 1 for this game. In practice this just means komi == 0.5.

Is it generally set for other handicap games on OGS? There are some quirks in OGS SGF output.

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The original game lists handicap of 1, which means komi is set to 0.5 and Black just gets the advantage of the first move, without significant komi given to White. I think that it would seem more appropriate to use the “B” property (instead of “AB”) for indicating Black’s first move in such situations.

According to the SGF standard, the “HA” property is a Go-specific property that should be 2 or larger. See SGF - Go (GM[1])

However, this seems somewhat contradicted by the SGF user guide (SGF Users Guide), which states that HA should simply be greater than 0, and explicitly lists “1” as an example possibility.

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