1. A method performed by a Diameter Routing Agent (DRA) for processing a Diameter message, the method comprising: receiving a Diameter message at the DRA from an origin device; establishing a routing decision context object in response to receiving the Diameter message, wherein the routing decision context object is associated with a destination device chosen to receive a previous message; evaluating a rule that includes a context object reference, wherein the evaluation includes accessing the routing decision context object based on the context object reference; and transmitting a message based on the evaluation of the rule.