MyCommand.php

<?php
namespace Application\Concrete\Console\Command;

use Concrete\Core\Console\Command;
use Concrete\Core\Error\UserMessageException;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;

class MyCommand extends Command
{
    protected function configure()
    {
        $errExitCode = static::RETURN_CODE_ON_FAILURE;
        $this
            ->setName('c5:my:command')
            ->setDescription('My command description')
            ->addEnvOption()
            ->addOption('option-a', 'a', InputOption::VALUE_REQUIRED, 'Option a description')
            ->addOption('option-b', 'b', InputOption::VALUE_REQUIRED, 'Option b description')
            ->setHelp(<<<EOT
You can use this as a command template.

To do task a, use the option a.
To do task b, use the option b.

Returns codes:
  0 operation completed successfully
  $errExitCode errors occurred

More info at http://documentation.concrete5.org/developers/appendix/cli-commands
EOT
            )
        ;
    }

    protected function execute(InputInterface $input, OutputInterface $output)
    {
        // Input
        $optionA = $input->getOption('option-a');
        $optionB = $input->getOption('option-b');

        // Output
        $output->write('Output message here');

        // Error
        if ($isError) {
            throw new UserMessageException('Error message here');
        }
    }
}