> For the complete documentation index, see [llms.txt](https://firstoken.gitbook.io/api-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://firstoken.gitbook.io/api-docs/api-reference/risk/payer-authentication-3d-secure/endpoints.md).

# Endpoints

The Risk Payer Authentication API provides three sequential endpoints that work together to implement the complete 3D Secure authentication flow. Each endpoint serves a specific purpose in the authentication process and must be called in the correct order.

### Endpoint Overview

#### Authentication Flow Sequence

| Endpoint             | Purpose                                           | When to Use                       |
| -------------------- | ------------------------------------------------- | --------------------------------- |
| **Setup**            | Initialize authentication process                 | Always - First step in every flow |
| **Check Enrollment** | Verify card enrollment and perform authentication | Always - After setup completion   |
| **Validate**         | Confirm challenge completion                      | Only when challenge is required   |

### Common Request Elements

#### Authentication

All endpoints require:

```
x-api-key: <YOUR_API_KEY>
Content-Type: application/json
```

#### Card Information Formats

All endpoints accept three card number formats:

* **Permanent Token**: `"{{token_id : detokenize}}"`
* **Temporal Token**: `"{{temp_token_id : transaction}}"`
* **Plain Card Number**: `"4111111111111111"`

#### Response Structure

All endpoints return standardized responses:

```json
{
  "status": "success|fail|error",
  "message": "Descriptive message",
  "data": { /* Endpoint-specific data */ }
}
```

### Implementation Notes

#### Sequential Dependencies

* **Setup** provides tokens needed for **Check Enrollment**
* **Check Enrollment** provides transaction ID needed for **Validate**
* **Validate** is only used when enrollment status is `Pending_authentication`

#### Error Handling

Each endpoint can return different error scenarios:

* Card validation errors (expired, invalid)
* Authentication system errors
* Network and system failures

#### Cardinal Commerce Integration

* **Setup** provides device data collection URL
* **Check Enrollment** uses device data and may trigger challenges
* **Validate** confirms challenge completion results

### Next Steps

Explore the detailed documentation for each endpoint:

* [**Setup Authentication**](/api-docs/api-reference/risk/payer-authentication-3d-secure/endpoints/setup.md) - Initialize the authentication process
* [**Check Enrollment**](/api-docs/api-reference/risk/payer-authentication-3d-secure/endpoints/check-enroll.md) - Verify card enrollment and perform authentication
* [**Validate Authentication**](/api-docs/api-reference/risk/payer-authentication-3d-secure/endpoints/validate.md) - Validate challenge completion results

Each endpoint page includes complete request/response examples, parameter definitions, and integration guidelines.