The program nauty
comes with gtools
which contains, among others, several generation programs like geng, genbg, ... I was wondering whether there is some article or other source describing the details of the algorithm used. I assume that the technique described in 'Isomorph-free exhaustive generation' is used, but I was interested in knowing which construction operations are used for each class and which was the criterion to select the parent for a given graph.
The main reason I want to know this, is that I see that there is the possibility to write plugins for these generation programs, but I would like to know a bit more about the program details before I try to find efficient ways to bound the process to get to the specific structures I'm interested in.