PayPal Permissions API - what is returned to return_url?

Question

I realize this is a simple question, but I have read all the documentation and can't find the answer. When you do a PayPal Permissions API call, it redirects back to the return_url you provided. At this point, the directions say,

Set up your request and call the GetAccessToken API operation.

Specify the request token in the token field.
Specify the verification code in the verifier field.

However, it does not say how it is you receive the request token and verification code. I assume that I can get them from $_GET. Older information on the internet lists $_GET['token'] but not anything for the verification code, so I don't trust that information to still be up-to-date.

In short, what are the keys in $_GET for the request token and the verification code?

EDIT

I have already tried finding out this information using the sandbox, but on the landing page at PayPal, I get, "Oops! We're sorry, your transaction has timed out. Please retry your transaction." There is no way for me to trigger the final step of the process.

Answer 1

The return URL should have request_token and verification_code, in the URL query string, and these are the keys for $_GET. For GetAccessToken you use the value from request_token as the token parameter, and verification_code value as the verifier parameter.