Zapier’s Catch Hook trigger ingests ProhostAI webhooks directly — no glue code required to land the event. Catch Hook does not verify HMAC signatures, though, so anyone who learns the URL can post arbitrary events into your Zap. Either accept that risk for low-value automation, or add a Code by Zapier step that verifies before branching.

1. Create the Zap — pick Webhooks by Zapier → Catch Hook as the trigger. Copy the https://hooks.zapier.com/hooks/catch/… URL.
2. Subscribe in ProhostAI — paste that URL into Settings → Webhooks, pick the events you want, save.
3. Sample the right schema — in ProhostAI, fire Send test on one of the events you actually subscribed to so Zapier samples the real shape. The auto-fired webhook.verification event has a generic stub body that won’t match any real event — if Zapier samples that, your downstream steps see the wrong fields.
4. (Optional) Verify the signature — HMAC verification needs the raw request bytes, but standard Catch Hook parses the JSON body and discards the raw payload — raw_body is not exposed. To verify, switch the trigger to Webhooks by Zapier → Catch Raw Hook (it surfaces raw_body and the request headers) and re-parse the JSON yourself in a Code by Zapier → Run Python step. Downstream Zap steps then read fields off the dict you build, not the trigger.
   python # Trigger: Webhooks by Zapier → Catch Raw Hook import hmac, hashlib, json secret = "whsec_your_signing_secret" # set in Zapier env raw_body = input_data["raw_body"] # only available from Catch Raw Hook sig = input_data["x_webhook_signature"].removeprefix("sha256=") expected = hmac.new(secret.encode(), raw_body.encode(), hashlib.sha256).hexdigest() if not hmac.compare_digest(expected, sig): raise ValueError("Invalid signature — drop") # Re-parse so downstream steps can map data.* fields event = json.loads(raw_body) output = {"verified": True, "event": event["event"], "data": event["data"]}

   Sticking with Catch Hook? Skip this step — HMAC verification isn’t possible without the raw bytes. Anyone who learns the Zap URL can post arbitrary events; accept that for low-value automation only.

Slack does NOT accept ProhostAI webhooks directly. ProhostAI sends an envelope shaped { "event": "…", "id": "…", "data": { … } }; Slack’s incoming-webhook endpoint requires { "text": "…" } or a blocks: […] array. If you paste a https://hooks.slack.com/services/… URL into ProhostAI it will 400 on every delivery.

Pick the easiest of these three options:

1. Slack Workflow Builder — webhook trigger. Inside Slack, open Tools → Workflow Builder, create a workflow with a From a webhook trigger, define variables that match the ProhostAI envelope (event, data.guest_full_name, etc.), then add a Send a message step. Paste the workflow’s URL into ProhostAI. No code, no middleman, but limited formatting.
2. Zapier middleman. Catch Hook (above) → Slack — Send Channel Message action. Lets you template {{event}} / {{data__listing_title}} into the Slack message. Pays a Zapier task per delivery.
3. Custom Cloudflare Worker. See the next tab. Best fit when you want HMAC verification + rich Slack blocks formatting and you don’t want to pay per event.

A complete reference Worker: verify the HMAC, branch on event, and post a Slack blocks message for autopilot.escalation. Drop into a fresh wrangler init project, set WEBHOOK_SECRET and SLACK_WEBHOOK_URL as secrets, paste the Worker URL into ProhostAI, done.