# Authenticate a client

Now that you have created a client when you want to perform an API request, you must first authenticate and receive an OpenCRVS **access token**. The token endpoint is OAuth 2.0 compliant.

{% hint style="warning" %}
**Client access tokens are valid for a maximum of 10 minutes. After it expires you must authenticate again to retrieve a new access token.**
{% endhint %}

{% hint style="info" %}
You can use our [Postman collections](https://github.com/opencrvs/opencrvs-countryconfig/tree/master/postman) to test all client functionality. [Postman](https://www.postman.com/) is a tool you can download to test API access before building your integrations.
{% endhint %}

**URL**

```
POST https://auth.<your_domain>/token?client_id=<client_id>&client_secret=<client_secret>&grant_type=&grant_type=client_credentials
```

#### **Request payload**

Example URL

```
https://auth.<your_domain>/token?client_id=2fd153ab-86c8-45fb-990d-721140e46061&client_secret=8636abe2-affb-4238-8bff-200ed3652d1e&grant_type=&grant_type=client_credentials
```

| Query parameter | Sample value                           | Description                                                              |
| --------------- | -------------------------------------- | ------------------------------------------------------------------------ |
| `client_id`     | `2fd153ab-86c8-45fb-990d-721140e46061` | The client id used in the authentication process for system clients.     |
| `client_secret` | `8636abe2-affb-4238-8bff-200ed3652d1e` | The client secret used in the authentication process for system clients. |
| `grant_type`    | `client_credentials`                   | The only supported grant type is client\_credentials                     |

#### **Request Response**

```
{
    "access_token": "eyJhbGciOiJSUzI1NiIsInR5cCI6Ikp...",
}
```

The token is a [JWT](https://jwt.io/) containing with the following structure and must be included as a header:**`Authorization: Bearer <token>`** in all future API requests. The content of an OpenCRVS access token looks like this:

#### **Token Header**

| Parameter | Sample value | Description                 |
| --------- | ------------ | --------------------------- |
| `alg`     | `RS256`      | Signing algorithm.          |
| `typ`     | `JWT`        | This value is always `JWT`. |

#### **Token Payload**

| Parameter | Sample value                 | Description                                                                                                                                                                                                                                |
| --------- | ---------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `scope`   | `['recordsearch']`           | An array of OpenCRVS roles for authorization permissions to access. These are defined as a feature of the OpenCRVS core. Approved scopes are `health`, `nationalId`, `ageCheck`. If you require a new scope, please open a feature request |
| `iat`     | `1593712289`                 | When the JWT was created.                                                                                                                                                                                                                  |
| `exp`     | `1594317089`                 | When the JWT expires - For clients this is set to 10 minutes by default, but this is configurable in the resources package.                                                                                                                |
| `aud`     | `['opencrvs.auth']`          | An array of services that will respond to this JWT.                                                                                                                                                                                        |
| `iss`     | `'opencrvs.auth'`            | The issuing service of the JWT.                                                                                                                                                                                                            |
| `sub`     | `'5ee75eb2104ccf88d9ac0c3d'` | A unique client id in our database.                                                                                                                                                                                                        |


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://documentation.opencrvs.org/v1.8/technology/interoperability/create-a-client/authenticate-a-client.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.