X) How are you outputting it? $contact_numbers is an array of objects. I guess in your case you are looking for a particular number so maybe just grab the first one
<?php
$verify_phone = $this->Html->ifSet($contact_numbers[0]->number);
?>
<script>
window.intercomSettings = {
app_id: "app_id",
phone: "<?php echo $verify_phone; ?>",
name: "<?php echo $this->Html->_($contact->first_name, true) . ' ' . $this->Html->_($contact->last_name, true);?>",
email: "<?php echo $verify_email; ?>", // Email address
user_hash: "<?php echo $email_sig; ?>" // HMAC using SHA-256
};
</script>
You may also want to submit the $type argument to Contacts::getNumbers() to get only 'phone' type numbers.