Execute a Closure after command runs without errors or has any errors

With Laravel scheduler you can execute a Closure when a command runs without errors with the onSuccess() method and also when a command has any errors with the onFailure() method.

protected function schedule(Schedule $schedule)
{
    $schedule->command('newsletter:send')
        ->mondays()
        ->onSuccess(fn () => resolve(SendNewsletterSlackNotification::class)->handle(true))
        ->onFailure(fn () => resolve(SendNewsletterSlackNotification::class)->handle(false));
}

Tip given by @wendell_adriel