mkptools are broken up into simple scripts:
mkpskel takes a distribution file as an argument and generates a
skeleton; it guesses the extract method, the package name, and so forth,
and generates populated Makefile and distinfo and empty pkg-descr,
pkg-comment, and pkg-plist.
mkpextr goes through the extract phase, and generates what it believes
are the necessary variables necessary to build the port. It guesses the
work source directory, what the Makefile is called, whether it has
configure, whether to use libtool, and other bits such as wildly
guessing kde, qt, gtk, gnome, and ssl requirements. Run it in a port
directory, and it generates Makefile.extr.
mkpmerge merges the results from mkpskel and mkpextr (and will later
merge the results from the other phases) into Makefile.
mkpclean cleans up any extra files that may be hanging about.