In addition to the python and XML interface to RSGISLib, there is a python utility to generate and execute a tempory XML file using command line arguments (rsgiscmd). Only the commands that don’t use XML children are available, which is still a large number (over 300).
Using the -h flag and algorithm name it’s possible to print all the available commands to the screen, by piping to grep you can search within this list. For example, I know there is a command within vectorutils to add a column with FID to a Shapefile. I can search for it using:
rsgiscmd -h vectorutils | grep 'fid'