# Constructor

## Appmixer

| Method                                      | Description                                                                                                                                                                                                                                                                             |
| ------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `Appmixer({ baseUrl })`                     | A constructor function to create an instance of the Appmixer SDK. Pass the base URL of the engine (Appmixer API).                                                                                                                                                                       |
| `appmixer.set(key, value)`                  | Set a property on the appmixer SDK object. Currently only `accessToken` should be set to be able to make calls to the Appmixer API.                                                                                                                                                     |
| `appmixer.onInvalidAccessToken(callbackFn)` | Allows setting a callback function that will be called whenever the current access token on the SDK is not valid. More information can be found on the [Managing Authentication ](https://docs.appmixer.com/6.0/v4.3/tutorials/managing-authentication#check-token-expiration)tutorial. |