[2603.00214] Agentic Scientific Simulation: Execution-Grounded Model Construction and Reconstruction

Computer Science > Software Engineering arXiv:2603.00214 (cs) [Submitted on 27 Feb 2026] Title:Agentic Scientific Simulation: Execution-Grounded Model Construction and Reconstruction Authors:Knut-Andreas Lie, Olav Møyner, Elling Svee, Jakob Torben View a PDF of the paper titled Agentic Scientific Simulation: Execution-Grounded Model Construction and Reconstruction, by Knut-Andreas Lie and 3 other authors View PDF HTML (experimental) Abstract:LLM agents are increasingly used for code generation, but physics-based simulation poses a deeper challenge: natural-language descriptions of simulation models are inherently underspecified, and different admissible resolutions of implicit choices produce physically valid but scientifically distinct configurations. Without explicit detection and resolution of these ambiguities, neither the correctness of the result nor its reproducibility from the original description can be assured. This paper investigates agentic scientific simulation, where model construction is organized as an execution-grounded interpret-act-validate loop and the simulator serves as the authoritative arbiter of physical validity rather than merely a runtime. We present JutulGPT, a reference implementation built on the fully differentiable Julia-based reservoir simulator JutulDarcy. The agent combines structured retrieval of documentation and examples with code synthesis, static analysis, execution, and systematic interpretation of solver diagnostics. Underspecifie...