In response to: https://msamgan.com/boilerplate-for-creating-a-shell-script

fish_starter_script.fish

#!/usr/bin/env fish

# Strict Mode and Tracing
set -e
set -u
if set -q TRACE; and test "$TRACE" = 1
    set -x
end

# Help Message
if test (count $argv) -gt 0; and test $argv[1] = '-h' -o $argv[1] = '--help'
    echo 'Usage: ./script.fish arg-one arg-two'
    echo 'This is an awesome fish script to make your life better.'
    exit
end

# Main Function
function main
    echo do awesome stuff
end

# Completion
complete -c $PROGRAM_NAME -n '__fish_use_subcommand' -a 'arg-one' -d 'The first argument'
complete -c $PROGRAM_NAME -n '__fish_use_subcommand' -a 'arg-two' -d 'The second argument'

# Call main function with arguments
main $argv