Abstract
Multi-agent systems need protocols to coordinate among agents implemented by different owners. However, specifying coordination protocols for many participating agents is a complex task. A protocol composition approach, which can reduce the complexity of specifying such a coordination protocol, must specify how to compose coordination protocols in a composition configuration. Current protocol compositions cannot sufficiently reduce the complexity because composing a protocol several times requires the specification of too many configurations. We propose a protocol composition approach that can specify composition configurations in an abstract way. We assign metadata to the messages in a coordination protocol and use the metadata to specify the configuration. An abstract configuration using metadata can be applied to various protocol compositions and can reduce the number of specifications required for configuration composition.