App::CLI::Command::Help (3pm)

    package MyApp::Help;
    use base qw(App::CLI::Command::Help);

    sub run {
        my ($self, @args) = @_;
        # preprocess
        $self->SUPER(@_);       # App::CLI::Command::Help would output PODs of each command
    }

Your command class should be capitalized.

To add help message , you just add pod in command class:

package YourApp::Command::Foo;

=head1 NAME

YourApp::Command::Foo - execute foo

=head1 DESCRIPTION

blah blah

=head1 USAGE

....

=cut