# Does the Cosumi Go site sometimes get the score wrong?

Cosumi claims that I won this game by 37 points:

But it looks even to me.

Am I missing something, or does the site sometimes get the score completely wrong?

EDIT:

Strange. The next morning, the same URL shows the upper-right corner as captured:

That might account for the score but, as far as I can tell, White still owns that territory.

Something strange is going on here. (Does Cosumi have a bug-reporting mechanism?)

• The score is wrong, both white groups are alive Sep 7, 2020 at 9:23

You are right that the top right belongs to White with correct play, but according to the programme Sabaki White wins by one point (because they have a captive). It is conceivable, but somewhat unlikely, that White could make enough errors for Black to win.

### The score

Sabaki calculates the score like this for area scoring:

and like this with territory scoring:

### The top right

To be on the safe side, I plugged your SGF into KataGo (via Sabaki), and it showed me a ko in the top right that Black cannot win: not only do they have hardly any threats, even if they did, they could not finish the ko in their favour.

``````\$\$Bcm1 Trying for a ko
\$\$ +---------+
\$\$ |..XOO.a25|
\$\$ |.X.XO.O1c|
\$\$ |..,XXO4d3|
\$\$ |.XXXXXOOO|
\$\$ |..XOXOXXO|
\$\$ |XXOOOOX.X|
\$\$ |OOOOOX.X.|
\$\$ |....OX.X.|
\$\$ |.O..OOX..|
\$\$ +---------+
``````

Unfortunately for Black, White simply has to connect with ➅ at a and Black has no way of finishing the ko to kill White. White can just wait for Black to run out of threats and then capture at c and d.

Black’s only chance is if White plays the ko wrongly, for example:

``````\$\$Wcm6 White messes up (9 retakes, 13 @ 7)
\$\$ +---------+
\$\$ |..XOO36OX|
\$\$ |.X.XO2OX1|
\$\$ |0.,XXOO.X|
\$\$ |9XXXXXOOO|
\$\$ |57XOXOXXO|
\$\$ |XXOOOOX.X|
\$\$ |OOOOOXxX.|
\$\$ |....OX.X.|
\$\$ |.O..OOX..|
\$\$ +---------+
``````
• capturing ➅ instead of connecting at ⓫,