Old version of the AJAX response template (http://blog.the-inspired-ones.de/ajax-uniform)

contact-send.php

<?php
header::contentType('application/json');

$errors = '';
// check each parameter of the request if it is erroneous
foreach (array_keys(get()) as $field) {
    $errors .= $form->hasError($field) ? "\"$field\"," : '';
}
// strip trailing comma
$errors = substr($errors, 0, -1);

?>
{
    "success": <?php e($form->successful(), 'true', 'false')?>,
    "message": "<?php echo trim($form->message()) ?>",
    "errors": [<?php echo $errors ?>]
}