Abstract
Neural Architecture Search (NAS) methods have become increasingly efficient, yet they remain constrained by manually engineered search spaces that require substantial domain expertise and must be rebuilt for every new task. Large Language Models (LLMs) can generate architectures in an open-ended space, but how to optimally divide the labor between LLM-driven design and NAS-driven search remains unexplored. We propose a mechanism that bridges these two paradigms: an LLM produces a high-quality seed architecture, then decomposes it into a "slotted architecture", a scaffold with named, interchangeable module slots that automatically defines a bounded, task-specific search space for conventional NAS to explore, without manual engineering.
We instantiate this mechanism in AgentNAS, a modular three-phase pipeline in which each component's contribution can be measured independently. On 17 tasks spanning classification, dense regression, segmentation, and multi-label tagging across diverse modalities (NAS-Bench-360 and Unseen NAS), AgentNAS establishes a new state of the art on 11 tasks, outperforming published baselines including task-specific expert designs.
Ablation studies show that the two search mechanisms are broadly complementary: the LLM-generated seed already surpasses published baselines on the majority of tasks, and NAS delivers additional gains in most cases through combinatorial recombination across slots, a mode of search that independent LLM samples cannot replicate. These patterns hold across three LLMs of different capability levels, confirming that the division of labor is robust.
Our code is available at GitHub.
Blogger's Review: The introduction of AgentNAS not only enhances the efficiency of neural architecture search but also provides new insights into the collaboration between LLMs and NAS. By effectively designing task-specific search spaces, AgentNAS demonstrates significant potential in multi-task environments, making it a worthy subject for further exploration and research.