Control Structures of Rule-Based Agent Languages

An important issue when defining a rule-based agent programming language is the design of interpreters for these programming languages. Since these languages are all based on some notion of rule, an interpreter must provide some means of selection from a set of such rules. We provide a concrete and intuitive ordering on rules on which this selection can be based. This ordering is inspired by the common sense metaphor of intelligent agents in Artificial Intelligence. Furthermore, we provide a language with a formal semantics for programming agent interpreters. The main idea is not to integrate this language into the agent language itself, but to provide the constructs for building interpreters at another (meta) level of specification. The operational semantics is accordingly specified at the meta level, by means of a (meta) transition system. Using this language we make a comparison between several interpreters for agent languages in the literature.