How do I install the Kicad Emsim skill?

Run npx skillmds@latest add avatarsd/kicad-emsim in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Kicad Emsim safe to use?

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Which AI agents work with Kicad Emsim?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Kicad Emsim free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Kicad Emsim?

AvatarSD (@avatarsd) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Kicad Emsim by avatarsd — Agent Skill

Name: Kicad Emsim
Author: AvatarSD

Kicad Emsim

Electromagnetic field simulation of a KiCad board via gerber2ems + openEMS (dockerized, headless): S-parameters, impedance, and E-field PNG visualizations fed back to the agent. Use when asked to simulate a board's EM behavior, check impedance of traces, or visualize fields.

AvatarSD 09eaf0e 1.9 KB Updated Sep 17, 2026

File contents

EM simulation (gerber2ems + openEMS)

Engine: $(kx root)/kicad_lib/emsim.py. STATUS: chain VALIDATED — meander_loose example simulated end-to-end (rc 0; |S11|≈1 + 455 ps delay on the open meander = physically correct). Image gerber2ems (6.6 GB); rebuild if missing: docker build -t gerber2ems $(kx root)/.tools/gerber2ems/. NEVER mount over /home/docker — it shadows the image toolchain; emsim.run mounts at /home/docker/sim.

Flow

emsim.prepare(pcb, workdir) — gerbers+drill+pos via fab.py (names already match), stackup.json translated from the board's (setup (stackup ...)), simulation.json template.
Fill ports in simulation.json (width/length in µm, impedance, layer index, excite flag) and traces (start/stop port indices) — ports sit at position-file footprint locations (use simulation-port footprints on the board for clean port placement).
emsim.run(workdir, export_field=True) — dockerized gerber2ems -a --export-field: geometry → FDTD → postprocess.
Read the outputs: ems/*.csv S-params/impedance; field PNGs are the agent feedback — Read them, check field concentration against expectations (return paths, gaps, stubs). VTR dumps open in ParaView for the user.

Notes

Frequency range/grid in SIM_TEMPLATE: 0.2–6 GHz, sane FR-4 defaults; finer grids explode runtime (FDTD is O(cells × steps)).
Worked examples: .tools/gerber2ems/examples/* (differential pair, filters, stubs) — copy a simulation.json from the closest one.
Docker daemon does its own networking — image build/pull works even though the agent sandbox blocks direct DNS.

---name: kicad-emsimdescription: Electromagnetic field simulation of a KiCad board via gerber2ems + openEMS (dockerized, headless): S-parameters, impedance, and E-field PNG visualizations fed back to the agent. Use when asked to simulate a board's EM behavior, check impedance of traces, or visualize fields.---# EM simulation (gerber2ems + openEMS)Engine: `$(kx root)/kicad_lib/emsim.py`.STATUS: chain VALIDATED — meander_loose example simulated end-to-end(rc 0; |S11|≈1 + 455 ps delay on the open meander = physically correct).Image `gerber2ems` (6.6 GB); rebuild if missing:`docker build -t gerber2ems $(kx root)/.tools/gerber2ems/`. NEVER mount over/home/docker — it shadows the image toolchain; emsim.run mounts at/home/docker/sim.## Flow1. `emsim.prepare(pcb, workdir)` — gerbers+drill+pos via fab.py (names already match), `stackup.json` translated from the board's `(setup (stackup ...))`, `simulation.json` template.2. **Fill ports** in simulation.json (width/length in µm, impedance, layer index, excite flag) and `traces` (start/stop port indices) — ports sit at position-file footprint locations (use simulation-port footprints on the board for clean port placement).3. `emsim.run(workdir, export_field=True)` — dockerized `gerber2ems -a --export-field`: geometry → FDTD → postprocess.4. Read the outputs: `ems/*.csv` S-params/impedance; **field PNGs are the agent feedback** — Read them, check field concentration against expectations (return paths, gaps, stubs). VTR dumps open in ParaView for the user.## Notes- Frequency range/grid in SIM_TEMPLATE: 0.2–6 GHz, sane FR-4 defaults; finer grids explode runtime (FDTD is O(cells × steps)).- Worked examples: `.tools/gerber2ems/examples/*` (differential pair, filters, stubs) — copy a simulation.json from the closest one.- Docker daemon does its own networking — image build/pull works even though the agent sandbox blocks direct DNS.

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