Authentication when using the API is currently optional. Using an API token will create all of your images in a user account so they can be managed using the user interface.
Generating an API Token
Register a user account, sign in and click the "My Images" link in the header. Click the "Generate" button to generate an API token.
Using an API Token
Include this HTTP header in your API requests:
Authorization: Token token="<put your API token here>"