AGENT-0

The first agent-oriented programming language, introduced by Yoav Shoham, in which agents are defined by a formal mental state (beliefs, capabilities, commitments) and interact via speech-act-typed primitives (INFORM, REQUEST, UNREQUEST). AGENT-0 concretises agent-oriented programming as a specialisation of object-oriented programming where module state is a mental state and messages are speech acts constrained by honesty/consistency rules.

In this vault

Backlinks

Agent-Oriented Programming line 32

Linked Pages

Speech Act Theory

Philosophy-of-language framework (Austin, Searle, Vanderveken) in which utterances perform actions (illocutionary acts) — the semantic backbone of most Agent Communication Languages.

Sources

Foundations Of Illocutionary Logic — Searle & Vanderveken
Three Models for the Description of Language — Chomsky, foundations
Agent Communication And Institutional Reality

Applied in

Mental State

Formally specified beliefs, desires, intentions, and commitments attributed to an agent as its program state.

In this vault

Agent-Oriented Programming

Reference: Shoham, Y. (1993). Artificial Intelligence 60, Elsevier. Source file: shoam-aop.pdf. URL

Summary

Shoham introduces Agent-Oriented Programming (AOP) as a specialization of object-oriented programming in which the state of each module — now called an agent — is a mental state composed of beliefs, capabilities, decisions/choices, commitments, and obligations. Interpretation of these components is formally grounded in an extension of standard epistemic logics that adds temporality, obligation, decision, and capability operators.

Agents communicate via speech-act-inspired primitives (inform, request, offer, promise, decline, etc.), constrained by rules such as honesty and consistency. The paper defines a class of agent interpreters and presents AGENT-0, a concrete implemented language whose semantics is tied to the mental-state logic. Shoham also discusses “agentification” — converting arbitrary devices into AOP-programmable agents — and situates AOP against BDI architectures, speech act theory, and McCarthy’s Elephant2000.

Key Ideas

AOP as OOP specialization with mental-state components.
Agents constrained by honesty/consistency on communicative acts.
Speech-act-typed primitives as message types.
AGENT-0 language and interpreter.
“Agentification” of arbitrary devices.

Connections

Conceptual Contribution

Claim: Programming can be fruitfully specialised to an “agent” paradigm in which module state is a formally specified mental state and inter-module communication is a speech act constrained by rational/ethical rules.
Mechanism: Shoham extends standard modal-epistemic logic with temporal, obligation, decision and capability operators, defines the mental-state components of an agent (belief, capability, commitment, choice, obligation), then specifies a generic agent interpreter cycle (update mental state, execute commitments, handle incoming messages) and instantiates it in AGENT-0, whose programs are condition-action rules over mental state and whose messages are typed INFORM/REQUEST/UNREQUEST primitives.
Concepts introduced/used: Agent-Oriented Programming, Mental State, Commitment, AGENT-0, Speech Act Theory, Agentification, BDI, Honesty Constraint
Stance: foundational
Relates to: Establishes the mentalistic ACL stance later criticised by Agent Communication Languages - Rethinking the Principles and surveyed by Intelligent Agents Theory and Practice; AGENT-0’s speech-act primitives anticipate KQML as an Agent Communication Language and FIPA-ACL; the mental-state architecture is reused in An Interaction-oriented Agent Framework for Open Environments.