Pass web service application traffic through a proxy to gather more detail. Using a proxy helps dig into a website and look for vulnerabilities.
FoxyProxy is a Firefox extension for switching an internet connection between proxy servers based on URL patterns. It simplifies configuring browsers to access proxy servers.
Burp Suite is a popular penetration testing and vulnerability finder tool for checking web application security. To discover hidden flaws, route traffic through a proxy like Burp Suite. FoxyProxy can be used to turn it on and off.