Abstract: An agent executing on a server identifies a function provided from a PHP library and executed by a PHP server and monitors the function. The present system places an interceptor on a first function in order to the identity of a second function. The second function may be identified from the first function return value from the route object, argument, PHP program state, or some other part of the execution environment at the time the first function is intercepted. From the data analyzed at the time the first function is intercepted, the present system identifies the second function which is also modified with an interceptor. The second function is monitored via the interceptor to determine performance and is associated with a business transaction.