Connect Retreaver

What you need

1. Your lookup URL and an active API key, both on the callersift home page.
2. A Retreaver campaign that receives the calls you want screened.

Wire it up

1. Campaign → Webhooks → add a webhook that fires on inbound call, before the call routes to a buyer.
2. Set the method to POST, the URL to your lookup URL, and the body to caller_number=[caller_number]&api_key=YOUR_KEY. Form-encoded and JSON bodies both work.
3. The response is JSON: fraud_check is "allow" or "block", and fraud_check_comments carries the reason.
4. Route on fraud_check with a tag or routing rule: allow continues to your buyers; block sends the call to a dead-end target or drops it.

A lookup that fails or times out answers allow: an outage on the scoring path never blocks a genuine caller.

Prove it works

1. Send a test ping from the dashboard (see the Send a test ping guide) to confirm the key and URL answer.
2. Place one live call through the campaign and watch the verdict land in recent pings with the masked number and line type.