ATL*AS: An Automata-Theoretic Approach and Tool for the Verification of Strategic Abilities in Multi-Agent Systems

2025-10-20

AI Summary

This work addresses the model-checking problem for ATL* logic over both infinite and finite traces in multi-agent systems. We propose two symbolic reduction algorithms based on parity games, enabling the first unified and efficient verification for both trace semantics. Our approach integrates automata-theoretic constructions, binary decision diagram (BDD)-based symbolic representation, and parity game solving, thereby avoiding explicit state-space enumeration. Leveraging this methodology, we develop ATL*AS—an open-source tool that significantly outperforms existing tools on synthetic benchmarks and cybersecurity case studies: it achieves superior performance for finite-trace verification and markedly improved scalability. ATL*AS fills a critical gap in the landscape of symbolic ATL* verifiers and supports precise, formal verification of strategic capabilities in large-scale multi-agent systems.

Technology Category

• Multiagent Systems: Other Foundations of Multi Agent Systems
• Constraint Satisfaction and Optimization: Satisfiability Modulo Theories
• Cognitive Modeling & Cognitive Systems: Symbolic Representations

Application Category

• Semantics and Knowledge: Data modeling to support human-machine intelligence, including LLMs agents, intelligent system behavior, explanations, and user-friendly interactions
• Graph Algorithms and Modeling for the Web: Algorithms and analysis for heterogeneous, signed, attributed, multi-relational, temporal, higher-order, and annotated Web-related graphs
• Search and Retrieval-Augmented AI: Agentic search

Abstract

We present two novel symbolic algorithms for model checking the Alternating-time Temporal Logic ATL*, over both the infinite-trace and the finite-trace semantics. In particular, for infinite traces we design a novel symbolic reduction to parity games. We implement both methods in the ATL*AS model checker and evaluate it using synthetic benchmarks as well as a cybersecurity scenario. Our results demonstrate that the symbolic approach significantly outperforms the explicit-state representation and we find that our parity-game-based algorithm offers a more scalable and efficient solution for infinite-trace verification, outperforming previously available tools. Our results also confirm that finite-trace model checking yields substantial performance benefits over infinite-trace verification. As such, we provide a comprehensive toolset for verifying multiagent systems against specifications in ATL*.

Problem

• Verifying strategic abilities in multi-agent systems
• Developing symbolic algorithms for ATL* model checking
• Comparing infinite-trace and finite-trace verification performance

Innovation

• Symbolic reduction to parity games
• Novel symbolic algorithms for ATL*
• Implementing finite and infinite trace verification