In order to be competitive, telecommunications service providers need new technologies that facilitate the rapid introduction of validated services in a cost-effective manner. Service engineering is a new discipline in which the telecommunications sector addresses the technologies and engineering processes required for service creation. Concurrent with these studies the development of applications in the Internet shows a new way to design telecommunications services based on the mobile agent paradigm. This brings new concepts that fit the requirements of service engineering. Therefore merging the approaches enables improvement of the service creation process. We illustrate this by presenting a framework for the formal design of telecommunications services using mobile agent technology complemented with formal methods. The contribution of this work is twofold. First, it relies on the Reference Model of Open Distributed Processing (RM-ODP) and shows how to adapt its concepts to agent orientation. Second, it provides agent-based service designers with validation and verification tools to state the quality of their specifications.