OFAC Screening Webhook

A webhook lets a screening service push match events to your app in real time, instead of polling for results.

TL;DR

TL;DR: An OFAC screening webhook is a callback mechanism where a screening service notifies your application of match events in real time.

What a webhook does

With a webhook, the screening service calls your endpoint when something happens, rather than your app repeatedly asking. In sanctions screening, the event is typically a match: a counterparty that returns BLOCK, or a risk score that crosses a threshold. Your app receives the event and can act immediately, which is faster than polling on a schedule.

Why it matters for agent payments

Agent payments are event driven, so webhooks fit naturally. When SanctionsAI flags a counterparty, a webhook can trigger the STOP step of the 4-Gate Agent Payment Protocol, SCREEN, SCORE, STOP, STAMP, halting the payment before funds move. The underlying check still runs as one HTTP call under 100 ms against 19,218 SDN names and 947 OFAC-listed crypto wallets.

Designing the callback

Make the webhook idempotent, since delivery can retry, and secure it so only the screening service can call it. Record every event for your compliance trail, since OFAC liability is strict and penalties start at $356,000 per violation, and an unlogged block is a gap in the record. Design the payload to include the counterparty and the result, so the receiving system can act and log without a second lookup. A well shaped event is easier to audit than a bare notification.