Solved, here, means an "Ultra-weak" solution: We have a proof of the outcome of the game with perfect play (even if we don't have a full efficient description of an algorithm for optimal play).
Individual clarifications:
You resign now chess: Described here.
"Odds" chess: Unless otherwise clarified, white starts with less material.
If no clarification is provided, these should be taken as the rules sources, in order of priority:
The rules of a variant available on Lichess at the time the option was created.
The rules of a variant available on Chess.com at the time the option was created.
The rules of a variant described on Wikipedia's page for chess variants at the time the option was created.
@mods Antichess has been weakly solved and can be resolved YES, see https://en.wikipedia.org/wiki/Losing_chess
@evan @BoltonBailey Is there a list of what names mean what things? Is there any possibility of ambiguity between "losing chess" and "antichess"? The Wikipedia redirect seems to mostly answer my question, but as someone who doesn't track the world of weird chess variants this seems important. Perhaps more so for other entries than for antichess. (What is "you resign now chess"? I do not know and did not immediately find an answer.)
@EvanDaniel Losing chess and antichess are the same thing. For "You Resign Now Chess," see https://manifold.markets/BoltonBailey/will-you-resign-now-chess-be-solved
@evan Like I said, I gathered that they are, but what's the procedure by which I as a trader or mod can figure that out, starting from this market? Antichess seems clearer than some of the others. I'd like to figure out how to resolve this ambiguity once rather than every time another thing (maybe) gets solved.
@EvanDaniel I don't necessarily think there will ever be one consistent way to decide on exact rules for any one variant, particularly given that sometimes variants themselves have variants. As a rule of thumb, let's just say that the following rulesets should be used, in order of priority:
The rules of a variant available on Lichess at the time the option was created, if Lichess has a variant that could reasonably be construed as being the variant named.
The rules of a variant available on Chess.com at the time the option was created, if Chess.com has a variant that could reasonably be construed as being the variant named.
The rules of a variant described on Wikipedia's page for chess variants at the time the option was created, if one exists.
@BoltonBailey Would it also be reasonable to say that if someone solves a thing, and calls it one of the named things, and it's at least pretty close, it probably counts? Especially if we're dealing with variants-of-variants?
@EvanDaniel I feel there is a danger of some kind of bias here. For example, horde chess has two variants that are similar, but perhaps one is easier to solve than the other. If we say something like "if someone solves anything that could be construed as being named a certain way, then the correct price for the market for the name might be higher than the correct price for any individual variant.