sim-buddy

Drive local CAE, CFD, and FEA tools from a desktop AI assistant.

sim-buddy is a WorkBuddy / CodeBuddy plugin marketplace that lets an AI agent call the local sim CLI and operate engineering simulation software on your machine.

For Simplified Chinese docs, see README.zh-CN.md.

Plugins

Tier 1 — installed by default:

Plugin	Solver	License
sim-comsol	COMSOL Multiphysics	Commercial (offline .mph inspection works without COMSOL)
sim-openfoam	OpenFOAM	Open source (GPL); supports local or remote sim-server
sim-ltspice	LTspice	ADI freeware (free for personal use)
sim-installer	meta — teaches the agent how to install more solvers	—

Tier 2 — opt-in (ask the agent or run the magic incantation below):

Plugin	Solver	Notes
sim-matlab	MATLAB / Simulink	needs MATLAB on the machine (matlabengine links at install time)
sim-abaqus	Abaqus	needs Abaqus to run
sim-fluent	Ansys Fluent	pulls ansys-fluent-core (~100MB); needs Ansys + Fluent
sim-hfss	Ansys HFSS	pulls pyaedt (~100MB); needs Ansys AEDT
sim-mechanical	Ansys Mechanical	pulls ansys-mechanical-core; needs Mechanical
sim-simscale	SimScale cloud CAE	needs SimScale API key, no local CAE software
sim-workbench	Ansys Workbench	pulls ansys-workbench-core; needs Workbench

How It Works

You describe an engineering task
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    v
WorkBuddy / CodeBuddy loads the sim-buddy marketplace
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    v
The matching plugin SKILL shells out to the local sim CLI
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    v
sim CLI loads the installed driver (sim-plugin-<solver>)
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    v
The solver runs locally and returns artifacts/results

Install

Prerequisites:

• Windows 10/11
• WorkBuddy or a compatible CodeBuddy marketplace host, launched at least once
• Git for Windows

In a WorkBuddy / CodeBuddy chat, ask the assistant to run this PowerShell:

irm https://raw.githubusercontent.com/svd-ai-lab/sim-buddy/main/install.ps1 | iex

You can also run the same command directly in PowerShell.

The installer will:

1. Install uv if not already on PATH.
2. Install the global sim command with all Tier 1 plugins (uv tool install sim-cli-core --with sim-plugin-comsol --with sim-plugin-openfoam --with sim-plugin-ltspice --upgrade --force).
3. Clone / refresh this marketplace under ~/.workbuddy/plugins/marketplaces/sim-buddy/.
4. For each installed sim-plugin-<X>, junction plugins/sim-<X>/skill/ at its bundled _skills/<X>/ directory. SKILL.md ships with the driver release, so skill and driver can never drift. Tier 2 entries get appended to marketplace.json automatically.
5. Register the local marketplace in ~/.workbuddy/plugins/known_marketplaces.json and prompt you to restart WorkBuddy / CodeBuddy.

Add a Tier 2 solver

Either ask the agent ("install the Fluent plugin"), or run directly:

& ([scriptblock]::Create((irm https://raw.githubusercontent.com/svd-ai-lab/sim-buddy/main/install.ps1))) -AddSolvers fluent

Multiple at once:

& ([scriptblock]::Create((irm https://raw.githubusercontent.com/svd-ai-lab/sim-buddy/main/install.ps1))) -AddSolvers fluent,mechanical,matlab

The installer detects previously-installed plugins via uv tool list — no state file, just re-run and it stays current. Tier 2 install failures (e.g., sim-plugin-matlab when MATLAB is not on the machine) are soft — Tier 1 still ends up working.

Try It

After installation, restart WorkBuddy / CodeBuddy and ask:

Inspect this .mph file and summarize its physics, parameters, studies, and mesh state.

Run an OpenFOAM steady-state cavity tutorial and report the residuals.

Simulate this LTspice schematic, sweep R1 from 1k to 100k, plot output.

The agent loads the matching plugin SKILL, verifies the local sim environment, and runs commands like:

sim --version
sim plugin list
sim plugin doctor <solver>
sim check <solver>
sim connect --solver <solver>

Other Solver Plugins (still in flight)

sim-cli has ~50 solver plugin repos under svd-ai-lab; only the 10 listed above are published to PyPI as of now. The rest (CalculiX, SU2, Elmer, gmsh, LS-DYNA, MAPDL, ...) are tracked in sim-plugin-index and will land here once they release.

Troubleshooting

If the assistant cannot find sim, rerun the installer or run:

uv tool install sim-cli-core --with sim-plugin-comsol --with sim-plugin-openfoam --with sim-plugin-ltspice --upgrade --force

If a solver is not detected, the plugin may still work offline (e.g., COMSOL .mph inspection); live solving requires the local software:

sim check <solver>
sim plugin doctor <solver>

License

Apache-2.0. See LICENSE.

Feedback

Open an issue at svd-ai-lab/sim-buddy.