# Risk Service

The Risk Service helps clients monitor transactions to support fraud prevention and risk mitigation. It includes a robust rules engine and a set of APIs (Score, Retrieve Scores, and Update Scores) that enable real-time transaction risk scoring based on configurable rule layers.

Version: 2026.04.23.0

## Servers

Prod
```
https://api.nelnetpay.com/risk
```

UAT
```
https://api.uat.nelnetpay.com/risk
```

## Security

### basicAuth

[object Object]

Type: http
Scheme: basic

### bearerAuth

[object Object]

Type: http
Scheme: bearer
Bearer Format: JWT

## Download OpenAPI description

 - [Risk Service](https://docs.nelnetpay.com/_bundle/apis/risk-api-spec.yaml)

## Fraud

 - [POST /nps/risk/scores](https://docs.nelnetpay.com/apis/risk-api-spec/fraud/score_2.md): Submit a transaction for risk evaluation via NPS Token. Returns HTTP 200 for all outcomes; inspect `responseCode` to determine success. Success codes start with 'A'; error codes start with 'E'. The `e
 - [GET /nps/risk/scores/{uuid}](https://docs.nelnetpay.com/apis/risk-api-spec/fraud/read_1.md): Retrieve a previously scored transaction by its risk UUID for NPS Merchant. Returns HTTP 200 for all outcomes; inspect `responseCode` for success or error. The `entityId` query parameter must match th
 - [PATCH /nps/risk/scores/{uuid}](https://docs.nelnetpay.com/apis/risk-api-spec/fraud/update_2.md): Update a previously scored transaction via NPS Token. Returns HTTP 200 for all outcomes; inspect `responseCode` to determine success. The `entityId` in the request body must match the entity authorise
## Risk - Direct Merchants

## Risk - Payments API

## Risk Event Logs