Arbor: Tree Search as a Cognition Layer for Autonomous Agents
Original reporting by arXiv (cs.AI)

Optimizing large language model (LLM) inference for peak performance has historically demanded coordinated expertise from human engineering teams across the entire software and hardware stack. Traditional autonomous optimization systems, often limited to isolated targets and stateless evaluations, struggle with the vast, dynamic nature of these systems. A new multi-agent framework, Arbor, introduces a revolutionary approach to this complex problem.
Arbor fundamentally redefines autonomous optimization by integrating a structured tree search as a cognition layer for its agents. Unlike prior systems, Arbor maintains an explicit search tree of scored hypotheses, serving as shared working memory across agents. This dynamic memory evolves with every measurement, treating failures as crucial diagnostic signals that reshape subsequent exploration, continuously adapting as successes reveal new bottlenecks.
Robust architecture
At its heart, Arbor employs an Orchestrator agent to drive optimization, delegating to Domain Specialists across the inference stack. Critically, a dedicated Critic agent ensures stability through root-cause analysis and measurement validation, establishing a checks-and-balances system where no single agent can unilaterally steer the process. This intelligent decomposition of domain expertise and coordination protocols enables fully autonomous, multi-day optimization campaigns. The results are striking: Arbor achieves up to 193% inference throughput-latency Pareto improvement over vendor-optimized baselines. A single agent without this sophisticated harness, by contrast, plateaus quickly and crashes, highlighting Arbor’s robust and generalizable method across hardware platforms.
Arbor represents a significant leap in autonomous optimization, demonstrating that sophisticated multi-agent coordination can unlock unprecedented performance gains in highly complex, stateful environments like LLM inference. Its innovative architecture, featuring an Orchestrator and a critical stability-focused Critic agent, ensures not only aggressive optimization but also resilient, self-correcting operation over extended periods—an achievement that eludes single-agent systems. The framework's ability to evolve its understanding through diagnostic signals and adapt to dynamic bottlenecks highlights a new paradigm for intelligent system design, where adaptability and stability are paramount.
Broadening Autonomy's Scope
The implications of Arbor extend far beyond its immediate application in AI inference. This framework pioneers a blueprint for autonomous systems capable of managing and optimizing vast, intricate real-world operations, from large-scale cloud infrastructure and complex manufacturing processes to scientific discovery and sophisticated supply chain logistics. By treating failures as learning opportunities and fostering structured collaboration between specialized agents, Arbor points towards a future where AI systems can autonomously navigate, diagnose, and resolve challenges in environments too complex for human teams or traditional automation. This advancement promises to fundamentally reshape how industries approach efficiency and innovation, freeing human experts to focus on higher-level strategic challenges. It also sets a new standard for robust and intelligent AI, capable of continuous improvement and reliable operation across diverse and evolving technological landscapes.