This Burp extension was created to help bug hunters brute force parameters on a website, specifically with James Kettles param finder. Default paramater lists are great for beginning your enumeration, but a more targeted list may bare much more fruit. This extensions goes through your Burp history, and creates wordlists from the parameters of every request for each target in scope.
Future releases may add parameters to the list as Burp receives requests. Pull Requests welcome.
Thanks to @gaberust for his help with JSON recursion :)