Webhook Structuring

I am building a Webhook model so users can receive data from a messaging app. I have never created such a system before, and I'd like to get some feedback on my attempt. $url = 'https://www.example.com/user-webhook-request.php'; $handshakeKey = "1234abcd"; $data = array('title' => 'Hello', 'message' => 'World', 'url' => 'http://example.com/#check', 'image' => 'http://www.example.com/pics/file.jpg'

[TakamiChie]

基本的なWebhookの送信例