A network device for a mobile carrier network sends, to a third-party content platform, a client message including a first dedicated subscription parameter extension. The first dedicated subscription parameter extension indicates one or more subscription parameters for a data flow between a user equipment (UE) device that originated the client message and the third-party content platform. The network device receives, from the third-party content platform, a server message including a second dedicated subscription parameter extension. The second dedicated subscription parameter extension confirms the third-party content platform will abide by the one or more subscription parameters. The network device generates, based on the one or more subscription parameters, a policy enforcement rule for the data flow that relies, at least in part, on cooperation of the third-party content platform.