1. A method for using by an intermediary a request and a response specified by a policy to determine an action of the policy, the intermediary receiving communications between a client and one or more servers, the method comprising: a) identifying, by an intermediary between a client and one or more servers, a policy for a communication transmitted between a client and a first server of the one or more servers received by the intermediary, the policy specifying content of a request to be generated and identifying a second server to communicate the request, the intermediary generating, responsive to the policy, the request with content specified by the policy; b) transmitting, by the intermediary responsive to the policy, the request specified by the policy to the second server specified by the policy; and c) determining, by the intermediary, an action of the policy to take on the communication between the client and the first server based on the second server's response, received by the intermediary, to the request specified by the policy.