> ## Documentation Index
> Fetch the complete documentation index at: https://docs.xpaycheckout.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Argus

> xPay's in-house intelligence and fraud prevention system.

## What is Argus?

Argus is xPay's in-house intelligence and fraud prevention system. It evaluates payment risk automatically and helps merchants reduce repeat card fraud by identifying and blocking risky payment signals.

You can also opt in to contribute your own risk signals. If your business logic flags a card as risky, block its fingerprint and Argus will apply that signal to future payments.

<Note>
  For example, you can monitor [Early Fraud Warning (EFW) events](/developer-resources/webhooks/events/intentEvents/early_fraud_warning) and proactively block fingerprints according to your business logic.
</Note>

Use the [Block fingerprint by intent API](/developer-resources/endpoints/argus/block-fingerprint-by-intent) to add the card fingerprint from a successful payment intent to your merchant's blocklist.