The mailutils help command lists all available options and command
names along with short descriptions of what each of them does. It is
similar to the mailutils --help option.
A command name can be supplied as an argument to
help, in which case it will display a help page for that
particular command, e.g.:
mailutils help ldflags
will output help for the ldflags command. It is synonymous
to the --help option used with that particular command, e.g.:
mailutils ldflags --help.