openPASO

<p align="center"> <picture> <source media="(prefers-color-scheme: dark)" srcset="logo/openPASO_koralle_dunkel.gif"> <source media="(prefers-color-scheme: light)" srcset="logo/openPASO_graphit_transparent.gif"> <img src="logo/openPASO_koralle_dunkel.gif" alt="openPASO" width="200"> </picture> </p> <h1 align="center">openPASO</h1> <p align="center"><b>open Platform for Agentic Simulation and Optimization</b></p> <p align="center"> <a href="https://pypi.org/project/openpaso/"><img src="https://img.shields.io/pypi/v/openpaso?style=flat-square&color=FF6B4A&label=PyPI" alt="openpaso on PyPI"></a> <a href="https://open-paso.github.io/openPASO/"><img src="https://img.shields.io/badge/docs-website-FF6B4A?style=flat-square" alt="Documentation"></a> <a href="LICENSE"><img src="https://img.shields.io/badge/license-MIT-64748B?style=flat-square" alt="MIT licence"></a> <a href="https://www.python.org/"><img src="https://img.shields.io/badge/python-3.10--3.13-64748B?style=flat-square" alt="Python 3.10 to 3.13"></a> <a href="https://doi.org/10.5281/zenodo.20543501"><img src="https://img.shields.io/badge/DOI-10.5281%2Fzenodo.20543501-64748B?style=flat-square" alt="DOI"></a> <a href="https://open-paso.github.io/openPASO/solvers/"><img src="https://img.shields.io/badge/solvers-9-FF6B4A?style=flat-square" alt="9 solvers"></a> </p> <p align="center"> <i>Describe a physics problem in plain words.<br> An AI model picks a solver, writes its input, runs it, and checks the answer.</i> </p> <p align="center"> <a href="https://open-paso.github.io/openPASO/"> <img src="docs/assets/openPASO_film.gif" alt="openPASO in 29 seconds: describe the physics, openPASO picks the solver, runs it, and checks the result against the literature" width="800"> </a> <br>_{Click the film to watch it in full quality on the documentation website.} </p> > [!WARNING] > **openPASO is under active development, and we invite you to help.** It works and is used for > real simulations, but it is young: things change quickly and you will find rough edges. Try it, > tell us what broke, and share what you know about a solver. > See [Contribute](https://open-paso.github.io/openPASO/contribute/). ## What it does Simulation programs, called **solvers**, compute how things physically behave: how a part bends, how heat spreads, how air flows. They are powerful and hard to use, and each one has its own input format and its own traps. openPASO puts **nine of them behind one door** and lets an AI model open it: you describe what you want in a normal sentence, and the model picks a solver, writes the input, runs it, and checks that the answer is computed correctly. ## Quick start You need Python 3.10–3.13 and about ten minutes. One solver is enough to begin. ```bash pip install openpaso # the server, with scikit-fem as a first solver openpaso doctor # which solvers openPASO can use on this machine; no key, no network openpaso # starts the MCP server on stdio; Ctrl-C to stop ``` Missing a solver? `openpaso install ngsolve` (or `kratos`, `dune`, ...) checks first and installs only what is missing, the same way the server's `setup_backend` tool would. `openpaso` is the command your AI app's MCP configuration points at. Working from a checkout instead (to change the code, or to run `check_install.py`, which lists the solvers openPASO can use on your machine without a key or network): ```bash git clone https://github.com/open-PASO/openPASO.git cd openPASO python3 -m venv .venv && source .venv/bin/activate pip install -e . scikit-fem python check_install.py ``` Then connect an AI model, one of two ways: - **Option A — an AI app you already have** (Claude Code, Claude Desktop, Cursor): no extra cost. [Set it up →](https://open-paso.github.io/openPASO/use/ai-app/) - **Option B — your own OpenRouter key**: one command per simulation, any model. [Set it up →](https://open-paso.github.io/openPASO/use/api-key/) ## Solvers | | | | |---|---|---| | [scikit-fem](https://open-paso.github.io/openPASO/solvers/skfem/) | [NGSolve](https://open-paso.github.io/openPASO/solvers/ngsolve/) | [Kratos Multiphysics](https://open-paso.github.io/openPASO/solvers/kratos/) | | [DUNE-fem](https://open-paso.github.io/openPASO/solvers/dune/) | [FEniCSx](https://open-paso.github.io/openPASO/solvers/fenics/) | [deal.II](https://open-paso.github.io/openPASO/solvers/dealii/) | | [FEBio](https://open-paso.github.io/openPASO/solvers/febio/) | [4C Multiphysics](https://open-paso.github.io/openPASO/solvers/fourc/) | [SPARTA](https://open-paso.github.io/openPASO/solvers/sparta/) | ## Documentation Everything else is on the **[documentation website](https://open-paso.github.io/openPASO/)**: installing each solver, both ways of use step by step, all 24 tools the model gets, how openPASO checks an answer, coupling two solvers on one problem, troubleshooting, and a glossary for every word. ## Contribute Reports of what did not work, solver traps you know, and plain-language fixes to the documentation are all very welcome. One rule stands above the rest: **every improvement must help all simulations, not one example.** See [CONTRIBUTING.md](CONTRIBUTING.md) and the [Contribute page](https://open-paso.github.io/openPASO/contribute/). ## Licence and citation MIT licence. openPASO was first published as **OASiS**; the archived releases and the paper use that name. If you use openPASO in research, please cite: ```bibtex @software{openpaso2026, title = {openPASO: an open-source multi-physics and multi-code framework for verified computer simulations}, author = {Hermann, Alexander and Shojaei, Arman and Scheider, Ingo and Cyron, Christian}, year = {2026}, doi = {10.5281/zenodo.20543501}, url = {https://github.com/open-PASO/openPASO} } ``` <p align="center"> _{Helmholtz-Zentrum Hereon · Institute of Materials Mechanics &nbsp;·&nbsp; Hamburg University of Technology} </p>