TAG: A Decentralized Framework for Multi-Agent Hierarchical Reinforcement Learning

TL;DR

This paper introduces TAG, a decentralized framework for multi-agent hierarchical reinforcement learning that supports arbitrary hierarchy depth, improving scalability and performance over traditional methods.

Contribution

The paper presents TAG, a novel framework enabling fully decentralized, multi-level hierarchical reinforcement learning with a standardized interface and flexible agent integration.

Findings

TAG improves learning speed and final performance.

Hierarchical architectures outperform classical multi-agent RL baselines.

Decentralized organization enhances scalability and adaptability.

Abstract

Hierarchical organization is fundamental to biological systems and human societies, yet artificial intelligence systems often rely on monolithic architectures that limit adaptability and scalability. Current hierarchical reinforcement learning (HRL) approaches typically restrict hierarchies to two levels or require centralized training, which limits their practical applicability. We introduce TAME Agent Framework (TAG), a framework for constructing fully decentralized hierarchical multi-agent systems. TAG enables hierarchies of arbitrary depth through a novel LevelEnv concept, which abstracts each hierarchy level as the environment for the agents above it. This approach standardizes information flow between levels while preserving loose coupling, allowing for seamless integration of diverse agent types. We demonstrate the effectiveness of TAG by implementing hierarchical architectures that combine different RL agents across multiple levels, achieving improved performance over classical multi-agent RL baselines on standard benchmarks. Our results show that decentralized hierarchical organization enhances both learning speed and final performance, positioning TAG as a promising direction for scalable multi-agent systems.