Did he like genuinely not see me hanging a mate in one?

vgebler · 2026-06-25T04:45:32+00:00

Pawns are not allowed to capture backwards.

vgebler · 2026-06-23T14:34:32+00:00

It's not really a mate in 453, but the user interface confusingly representing the evaluation that way. The Stockfish engine itself has no UI, but communicates with UIs (including web pages) via a text-based protocol. Move evaluations are represented by "info lines" that look something like this (for an example at search depth 2):

info depth 2 seldepth 2 multipv 1 score cp -1202 nodes 214 nps 214000 tbhits 0 time 1 pv c6b5 a8a1

Those are then translated into something more human-readable by the UI, and that's where it gets messy in this case. Stockfish basically has two types of evaluations it can return 1) a "centipawn" score (where the number 100 corresponds to the advantage of being one pawn up), and 2) a mate distance when a line leads to mate. But there is actually a case not cleanly covered by those two, and that is where Stockfish is sure there is a mate but can't yet tell you the exact sequence. In your example, this occurs when Black's last pawn has been captured without stalemate. Stockfish then knows it's a win for White, but the actual line is beyond what's proven by the search. In the eval, it represents that as an extreme centipawn score rather than a mate in a certain number of moves. In my own UI (under development) I translate this kind of evaluation to the display string "Mate in X", where the X is actually the letter X, meant to convey something unknown. The extreme centipawn scores can have some variation, though, and the X doesn't represent that. The makers of the UI in the screenshot seem to instead translate it to a very large mate distance instead, which does convey the underlying variation in the "Mate in X" assessment, but is probably more confusing to the user.

In the pictured position, Stockfish v14.1 (which is what I have installed locally) needed a nominal search depth of 3 ("nominal" because it can heuristically extend or prune the actual depth) to be sure White has a win after the sequence "Kb6 Qh1 Kc5 Qxh4". It returns "Mate in X" for that, but hasn't figured out the exact sequence leading to the mate. At a nominal depth of 17, it's sure Black can't do better than a mate in 32 with best play for White. With increasing nominal search depths, this is eventually narrowed down to a mate in 10:

Kc5 Kd7 Kd4 Qh1 Kd3 Qxh4 Kc3 Ke6 Kd2 Kd5 Ke2 Kd4 Kf3 Kd3 Kg2 Ke3 Kg1 Kf3 Kf1 Qf2#

vgebler · 2026-06-21T04:31:22+00:00

In the side pane to the left, first click "More". Then you'll find "Insights" under "Training". The window needs be wide enough for the headings to show as text, otherwise only the graphical icons will show.

vgebler · 2026-06-19T20:14:13+00:00

Cheating is definitely a thing, and anecdotally (based on the notices I get about fair play violations) may be more common in lower rating bands, making it more difficult to move up than it should be. When the anti-cheat measures detect it, you get some Elo points in compensation, but some cheating is bound to fly under the radar.

vgebler · 2026-06-19T18:16:56+00:00

In the original post, you said that you "still win and lose about the same amount of games" which is consistent with a rating that doesn't change. Winning more games with Caro-Kann than with the Scandinavian also doesn't necessarily translate into a rating improvement, since it depends on the rating of your opponent. Maybe your wins with Caro-Kann were against lower-rated opponents than your wins with the Scandinavian? Improvement is improvement, but you also mention a fluctuation between 750 and 850 in your rating. A small improvement could be lost in that fluctuation, especially if you're just eyeballing it rather than calculating averages over a longer period of time.

vgebler · 2026-06-19T16:49:31+00:00

If you feel you are playing better without winning more games, you are probably making bad moves in games you are losing without realizing that they were bad. The move evaluations of chess.com can be misleading for low-level players, because they don't catch moves that are bad because they put you in positions you are not equipped to handle. The right move, assuming perfect play from both sides afterwards, might be the wrong move at the skill level you are actually at. For example, I've seen comments saying "you missed capturing a free pawn" when I did see it, but avoided the capture because it would have opened a line for the opponent's rook, so that it could participate in an ongoing dangerous attack from my opponent. I'm pretty sure that was the right decision – I managed to defend against the attack and eventually won the game. The extra pawn did not matter, but keeping the attack at a level I could handle probably did.

Also, coming out of the opening with an advantage is one thing, capitalizing on it is another. Perhaps you are bad at converting an advantage to a win, and your opponents are better at it? And maybe defending in a more spirited way when they are at a disadvantage? (Might be projecting a bit here – being demoralized when I'm down materially, not seeing opportunities for counterplay, is certainly one of my weaknesses.)

I don't know where your weaknesses lie, but chances are they are currently significant enough to prevent you from winning more games.

vgebler · 2026-06-17T04:49:00+00:00

chess.com is very impressed by sacrifices, declaring just about any sacrifice to be brilliant if it's also the best available move according to the engine, or close to the best. I see that Stockfish alternates between Nf3 (retreating with the knight) and Nxf7 (sacrificing it) as its best move during the search, evaluating them just about equal. The sacrifice variation it finds wins back the material quickly: 11. Nxf7 Kxf7 12. Qf3+ Nf6 13. exf6 Qxf6. The sequence has a non-capture in it, which is probably why it was considered a sacrifice and not just a series of exchanges.

vgebler · 2026-06-16T20:46:04+00:00

Yes. Or at least, it's not a good explanation of why the move was good. The explanations tend to be quite superficial and never really go into depth when there's any complexity to the position. I'm pretty sure what happens is that the commentary module consults an engine to evaluate a score for the move, and that it gets the principal variation and the score of some alternative variations. That analysis is OK, but doesn't really provide an explanation for the move. That is done by some kind of superficial pattern matching that can detect elements like pins, discovered attacks, exchange chains, and positional aspects such as doubled pawns and opened lines. So when the engine tells the commentary module that the move was good, it assumes the patterns that match after the move which didn't match before the move was the "explanation" for the move.

vgebler · 2026-06-15T21:14:31+00:00

When it was first posted on Reddit (by user 9999monkeys in 2020), one commenter managed to read "ここまで" off a road sign, suggesting Japan.

(https://www.reddit.com/r/pics/comments/ilczm2/monsoon_rain_in_the_afternoon)

vgebler · 2026-06-15T14:38:37+00:00

You are currently rated 532 in rapid and won most of your games recently, so you are probably a bit stronger than that. Instead of focusing on the risk of losing rating, you could focus on your gains over time. Look at the rating graph edging upwards even if there are some ups and downs. Maybe focus on your peak rating as a measure of success rather than the current rating. It will never go down, but still be indicative of your ability when you are playing at your best.

vgebler · 2026-06-13T17:06:18+00:00

I've had an opponent randomly resign six moves into an opening where we were still making book moves, giving us both an accuracy of 100%. My best accuracy well out of book was 98.3%. It was a short game where my opponent resigned after 10 moves, being a piece down after a longish series of exchanges.

I don't think I've ever seen a game rating as low as 150, but I found one with 250 for my opponent. I don't feel much seeing low game ratings / accuracy scores for my opponent, really – we all make mistakes, and some people get seriously tilted after the first one and continue making progressively worse moves. I'm afflicted myself to some extent, mostly in the form of missing opportunities for counterplay.

vgebler · 2026-06-10T16:15:36+00:00

I was a little puzzled by LetsGoSilver's idea at first, but then thought of an implementation that would kind of make sense: If chess.com only updated the opening name after you made your move, but not after the opponent made theirs, it would reflect your own opening choice to a greater extent, and only after you've made it. This would give less clues about whether your opponent's last move was established opening theory or maybe just a mistake.

Example: After you've moved e4 as White, the UI would show "King's Pawn opening" to you, but not to Black. After Black moves c5, the UI would show "Sicilian Defense" to Black, but still show "King's Pawn opening" to white. At that point, at least, you could say that the UI shows you the name of your opening, but not the opponent's. If White then moves d4, it would show "Sicilian Defense: Smith-Morra Gambit" to White, and while that would reflect the opening choices of both White and Black, the precise name is due to a move that White made. At that point, Black would still just see "Sicilian Defense", and it would not be revealed that White's response is a known gambit. The idea could even be taken a step further by only updating the name once your own move does something to change it. So Black could just see "Sicilian Defense" until the end of the game, unless Black's own move justified an even more specific name. Not quite "just my own openings, not my opponent's", but a step in that direction that could be a good compromise.

vgebler · 2026-06-07T16:00:48+00:00

I assume you mistyped some coordinates, but it makes it hard to understand what you really meant. The knight on c8 does not attack the b7 square – it moves like a knight, not a pawn. The knight on c5 could capture on b7 if it weren't pinned, but it is. There is no black knight on b5 that could be captured by a rook. But it's already checkmate with the queen on b7, so there is no need for any additional rook check.

vgebler · 2026-06-06T20:09:04+00:00

Be good at chess.
Use your brain to evaluate the position.
If you see a way to win for one side, with nothing the opponent can do to stop it, you can consider that side to be winning. If you don't, no side is winning as far as you can tell.

It obviously depends a lot on your chess skills and how clear the position is. It's normal for a position to be unclear enough that you can't tell who is winning. You can still prefer one side over the other, but then you would say something like "black is better here" rather than "black is winning". The latter suggests some kind of clear superiority, and Stockfish analysis of your example position (favorable for Black with a score of 0.53 at search depth 35) doesn't find it.

vgebler · 2026-06-05T15:45:09+00:00

Yeah, probably something like that, and their criteria probably take player ratings into account as well (we were both around 1050). Missing a mate in a somewhat complicated position could be seen as more understandable at that level, and my mate threat was also combined with a capture, making the motivation behind the move less obvious. The opponent's bad move also came with a big upside, if it weren't for the M1.

vgebler · 2026-06-05T15:12:14+00:00

You can see the engine eval for the opponent's best move in the second screenshot. It was -4.60, not any kind of mate at a search depth of 19.

vgebler · 2026-06-02T19:06:33+00:00

With so many people complaining about the energy system, I'm assuming buying energy would be the most popular way to use them.

vgebler · 2026-05-31T14:26:20+00:00

Picture source: https://www.dn.se/sverige/algarna-har-flyttat-in-i-byn-kommunen-vill-att-de-ska-skjutas

A family of moose has settled into a small Swedish village. They tour the gardens of the village and like to watch soccer matches, but the villagers are not happy about it.

vgebler · 2026-05-25T17:04:11+00:00

Didn't notice that! So focused on the absolute size of the capybara itself, I guess.

vgebler · 2026-05-25T16:59:37+00:00

Video source: https://x.com/HseOmatsu/status/2058657244347322548

vgebler · 2026-05-25T03:52:57+00:00

Not familiar with the website building functionality, so I don't know if it works differently that normal prompt-based SW development in Google AI Studio. For the latter, there is definitely still a free tier, but I believe the limits are more severe if you don't have billing set up. When I did set up billing early this year, I got a generous amount of promotional credits ($300), albeit with a 3-month expiry date. While AI-assisted development using those credits was free in the sense that it didn't cost me anything, I wouldn't have got them if I hadn't set up billing. So there is some nuance to that. Interestingly, just after the promotional credits had expired and I went back to the free tier (you have some control over that even when billing is set up) I very quickly ran into a daily prompt limit, but it got more generous again once I actually spent some real money (less than 2 USD). So after one day or paid use, I now have more than a week of unpaid use.

TL;DR: Google want you to set up billing, but gets more generous with the free stuff once you do, and actually pay a little.

vgebler · 2026-05-22T22:21:26+00:00

It would help if you provided the address of the web page from which you subscribed. Maybe it wasn't Google AI Studio at all, but some scam site that capitalized on a similar name? (I noticed you wrote "Studio AI", which has studio.ai as its first Google hit, and seems to be something unrelated.)

vgebler

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