Commitments with regulations: reasoning about safety and control in REGULA

Commitments provide a flexible means for specifying the business relationships among autonomous and heterogeneous agents, and lead to a natural way of enacting such relationships. However, current formalizations of commitments incorporate conditions expressed as propositions, but disregard (1) temporal regulations and (2) an agent’s control over such regulations. Thus, they cannot handle realistic application scenarios where time and control are often central because of domain conventions or other requirements. We propose a new formalization of commitments that builds on an existing representation of events in which we can naturally express temporal regulations as well as what an agent can control, including indirectly as based on the commitments and capabilities of other agents. Our formalization supports a notion of commitment safety. A benefit of our consolidated approach is that by incorporating these considerations into commitments we enable agents to reason about and flexibly enact the regulations. The main contributions of this paper include (1) a formal semantics of commitments that accommodates temporal regulations; (2) a formal semantics of the notions of innate and social control; and (3) a formalization of when a temporal commitment is safe for its debtor. We evaluate our contributions using an extensive case study.