Prefinery allows two forms of authentication -- both HTTP Basic Authentication as well as token-based authentication using a secret api key.
Log in to your Prefinery account and click the Settings → Your Settings menu in the upper right corner and choose API Access. Follow the instructions to create your unique API key.
Remember that anyone who has your API key has complete access to your account, so you'll want to guard this key just as you would your username and password. If you fear that your key has been compromised, you can easily generate a new one from within your account.
To use this method, simply append the api_key parameter to your requests, like so
To use this method, use your API key as the username and X as the password. Since lots of implementations assume a password, we'll use X as a dummy password. For example,
curl -u 706de3ef2:X https://api.prefinery.com/api/v2/betas/1/testers/1.json