[2603.25723] Natural-Language Agent Harnesses

Computer Science > Computation and Language arXiv:2603.25723 (cs) [Submitted on 26 Mar 2026] Title:Natural-Language Agent Harnesses Authors:Linyue Pan, Lexiao Zou, Shuo Guo, Jingchen Ni, Hai-Tao Zheng View a PDF of the paper titled Natural-Language Agent Harnesses, by Linyue Pan and 4 other authors View PDF HTML (experimental) Abstract:Agent performance increasingly depends on \emph{harness engineering}, yet harness design is usually buried in controller code and runtime-specific conventions, making it hard to transfer, compare, and study as a scientific object. We ask whether the high-level control logic of an agent harness can instead be externalized as a portable executable artifact. We introduce \textbf{Natural-Language Agent Harnesses} (NLAHs), which express harness behavior in editable natural language, and \textbf{Intelligent Harness Runtime} (IHR), a shared runtime that executes these harnesses through explicit contracts, durable artifacts, and lightweight adapters. Across coding and computer-use benchmarks, we conduct controlled evaluations of operational viability, module ablation, and code-to-text harness migration. Comments: Subjects: Computation and Language (cs.CL); Artificial Intelligence (cs.AI) Cite as: arXiv:2603.25723 [cs.CL]   (or arXiv:2603.25723v1 [cs.CL] for this version)   https://doi.org/10.48550/arXiv.2603.25723 Focus to learn more arXiv-issued DOI via DataCite (pending registration) Submission history From: Linyue Pan [view email] [v1] Thu, 26 Ma...