# Client

The Client object is a JSON-formatted object returned by the signed request in the [CanvasRequest](/docs/platform/canvas-framework/guide/canvas-request-object.md) object. It contains context information about the client app.

| Field          | Description                                                                                                                                                                                                                                                  |
| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `instanceId`   | The ID of a canvas app exposed on a Visualforce page. Used internally for canvas app instance management.                                                                                                                                                    |
| `instanceUrl`  | The URL of the Salesforce instance. For example, http://`instance`.salesforce.com. Used to preface the URLs returned by the [Links](/docs/platform/canvas-framework/guide/links-object.md) object.                                                           |
| `oauthToken`   | The OAuth access token that’s returned to the caller.                                                                                                                                                                                                        |
| `refreshToken` | The token that the client uses to authenticate a session. This value is returned only if the canvas app has “Perform requests on your behalf at any time (refresh_token, offline_access)” as one of the selected OAuth scopes; otherwise `null` is returned. |
| `targetOrigin` | The URL of the canvas app. Used internally for cross-domain communication between the page and the iFrame that contains the canvas app.                                                                                                                      |

The following code snippet shows an example of the Client object.

```nolang
"client":
{
    "instanceId":"06Px000000002JZ", 
    "instanceUrl":"http://instance.salesforce.com:8080", 
    "oauthToken":"00Dx0000X00Or4J!ARQAQJ34YLUq54RMTrQbxVoWUgorjFi3...", 
    "refreshToken":"00DD0000000K1NM!ARAAQGJVGOyMjh1jjqvShRpLuAq0ke...", 
    "targetOrigin":"http://instance.salesforce.com:8080"
}
```

**See Also**

- [CanvasRequest](/docs/platform/canvas-framework/guide/canvas-request-object.md)