GoTools is a life-and-death problem solving program, written by Thomas Wolf.
For more information read:
Note: This section seems to be about the online applet only.
GoTools seems to have been broken for quite some time now. It frequently misjudges even simple positions, or simply stops computation and displays the message "Interrupted" or, less frequently, "Internal Error". Worse, it often freezes in the middle of a computation, making it necessary to close the program and restart your browser.
It also often "forgets" the objective while navigating a solution, making it necessary to repeatedly redefine a problem.
New bug (surprise!): today, while solving a problem, it tried to place a stone in a illegal position (a position that was already occupied), and displayed a message to that effect while repeatedly trying to play the same move (and disallowing the calculation from being interrupted).
Last edit about "Bugs" here was in 2010, while "News" on the project page have their last entry from 2016 ("A number of updates and fixes were put in place for the Online - Go Guess page and the Online - GoTools Java Applet itself.") RueLue in 12-'18