The blockchain concept and technology are impacting many different research and application fields; hence, many are looking at the blockchain as a chance to solve long-standing problems or gain novel benefits. In the agent community several authors are proposing their own combination of agent-oriented technology and blockchain to address both old and new challenges. In this paper we aim at clarifying which are the opportunities, the dimensions to consider, and the alternative approaches available for integrating agents and blockchain, by proposing a roadmap and illustrating the issues yet to be addressed. Then, as both validation of our roadmap and grounds for future development, we discuss the case of Tenderfone, a custom blockchain integrating concepts borrowed from agent-oriented programming.

The contribution of this paper is twofold:

  • We present and discuss the dimensions of agent–blockchain integration (computation vs. interaction) and the impact on agent-oriented practice and blockchain, then we enumerate and analyze viable approaches to integration by considering what we call “agent-vs-blockchain” and “agent-to-blockchain” approaches, such as letting agents interact with the blockchain vs. modelling agents as smart contracts, or injecting blockchain and smart contract concepts into agents (e.g., programming agents through smart contracts). Accordingly, we propose two roadmaps for the exploration of the aforementioned approaches
  • We validate the first steps of our roadmaps through Tenderfone [16,19], which is a prototype of agent-oriented blockchain we designed and implemented, where smart contracts are empowered with autonomy through mechanisms endowing them control flow and asynchronous interaction means, showing the advantages of pushing smart contracts closer to agent abstraction.