Agent Drift: Quantifying Behavioral Degradation in Multi-Agent LLM Systems Over Extended Interactions
Abhishek Rath
TL;DR
This paper introduces agent drift as a long term stability issue in production multi agent LLM systems, identifying semantic, coordination, and behavioral drift and formalizing ASI to quantify drift across twelve behavioral dimensions. Using a theory grounded simulation framework across three enterprise domains, it demonstrates that drift can substantially degrade task success, increase latency and human intervention, and amplify inter agent conflicts. The authors propose and evaluate three mitigation strategies Episodic Memory Consolidation, drift aware routing, and adaptive behavioral anchoring, showing up to 81.5% drift reduction with notable overheads. The work highlights critical implications for deployment, AI safety, and governance, and provides a foundational framework for monitoring, measuring, and mitigating drift in long running agentic AI systems.
Abstract
Multi-agent Large Language Model (LLM) systems have emerged as powerful architectures for complex task decomposition and collaborative problem-solving. However, their long-term behavioral stability remains largely unexamined. This study introduces the concept of agent drift, defined as the progressive degradation of agent behavior, decision quality, and inter-agent coherence over extended interaction sequences. We present a comprehensive theoretical framework for understanding drift phenomena, proposing three distinct manifestations: semantic drift (progressive deviation from original intent), coordination drift (breakdown in multi-agent consensus mechanisms), and behavioral drift (emergence of unintended strategies). We introduce the Agent Stability Index (ASI), a novel composite metric framework for quantifying drift across twelve dimensions, including response consistency, tool usage patterns, reasoning pathway stability, and inter-agent agreement rates. Through simulation-based analysis and theoretical modeling, we demonstrate how unchecked agent drift can lead to substantial reductions in task completion accuracy and increased human intervention requirements. We propose three mitigation strategies: episodic memory consolidation, drift-aware routing protocols, and adaptive behavioral anchoring. Theoretical analysis suggests these approaches can significantly reduce drift-related errors while maintaining system throughput. This work establishes a foundational methodology for monitoring, measuring, and mitigating agent drift in production agentic AI systems, with direct implications for enterprise deployment reliability and AI safety research.
