1. A computer-implemented method for modifying an outbound content response, the method comprising: retrieving one or more rewriting rules from a rule data store; grouping rules by one or more content tags to which the rules apply; iterating through the rule groups; for each rule group, parsing the response to identify tags associated with a current tag-based rule group; and applying each rule in the rule group to perform a rewrite of identified tags based on an action specified by each rule; and finalizing the rewritten response for sending to a requestor, wherein the preceding steps are performed by at least one processor.