MASA: LLM-Driven Multi-Agent Systems for Autoformalization
Lan Zhang, Marco Valentino, André Freitas
TL;DR
MASA tackles the challenge of autoformalization by introducing a modular, multi-agent framework that orchestrates agents, LLMs, a knowledge base, a retriever, and theorem provers to convert natural-language math into formal Lean4 representations. The approach demonstrates a real-world use case on softmax and shows how specialized agents (autoformalization, critique, tool, and refinement) collaborate to produce and iteratively improve formalizations. Key contributions include a flexible MASA architecture, demonstration on real-world mathematics, and an empirical evaluation across multiple backends (e.g., $\text{Qwen}_{2.5-7\text{B}}$, $\text{GPT-4.1-mini}$) with notable gains in syntactic correctness and semantic alignment when applying iterative self-refinement, achieving 35.25% and 61.89% formalizations that are both syntactically correct and semantically aligned. The work advances AI-driven mathematical reasoning by enabling extensible, agent-based autoformalization workflows that can adapt to evolving formal libraries and provers.
Abstract
Autoformalization serves a crucial role in connecting natural language and formal reasoning. This paper presents MASA, a novel framework for building multi-agent systems for autoformalization driven by Large Language Models (LLMs). MASA leverages collaborative agents to convert natural language statements into their formal representations. The architecture of MASA is designed with a strong emphasis on modularity, flexibility, and extensibility, allowing seamless integration of new agents and tools to adapt to a fast-evolving field. We showcase the effectiveness of MASA through use cases on real-world mathematical definitions and experiments on formal mathematics datasets. This work highlights the potential of multi-agent systems powered by the interaction of LLMs and theorem provers in enhancing the efficiency and reliability of autoformalization, providing valuable insights and support for researchers and practitioners in the field.
