why click is based on optparse and not argparse
Applies only to optional args long help
Applies only to subcommands short help
Special mention to how to document positional args. The docs explains the intentional lack of help kwarg for positional args.
./thing.py -h
./thing.py subcommand --help
Lists all the subcommands with one line short description for each subcommand.
Lists detailed docs of one subcommand
My opinion having used both argparse and click, click is simpler cleaner and less time consuming.