robosimtools-mcp

An MCP server that exposes robosimtools.com's 12 robotics/simulation tools to AI agents. The tool logic here is the same code robosimtools.com serves to your browser — vendored into lib/ so this server is self-contained. All computation is local; nothing is uploaded.

This is the open-source MCP server for robosimtools.com. The website itself is a separate project; only the browser tools it already ships publicly are included here (see Vendored modules).

Tools

Tool	What it does
robosim_convert_rotation	Quaternion ↔ Euler (12 sequences) ↔ 3×3 matrix ↔ axis-angle ↔ URDF roll-pitch-yaw.
robosim_dh_to_urdf	Denavit-Hartenberg table → URDF joint chain (standard or modified/Craig).
robosim_diff_ardupilot_params	Diff two ArduPilot .param files; changed / added / removed.
robosim_mesh_mass_properties	STL/OBJ → mass, center of mass, full inertia tensor.
robosim_validate_urdf	Structural URDF validation — tree, inertia sanity, joint limits.
robosim_inspect_urdf	URDF → links, joints, kinematic roots, degrees of freedom.
robosim_xacro_to_urdf	Expand Xacro properties, macros, conditionals, includes → URDF.
robosim_urdf_to_mjcf	URDF → MuJoCo MJCF.
robosim_sdf_to_urdf	Gazebo SDF → URDF with correct relative joint origins.
robosim_step_to_urdf	STEP/IGES CAD → URDF with per-solid inertia (OCCT WASM kernel).
robosim_generate_sbom	Lockfile (npm/pip/cargo/go) → CycloneDX 1.6 SBOM.
robosim_cra_readiness	EU Cyber Resilience Act scoping wizard.

Every tool is read-only with no side effects.

Install

git clone https://github.com/RahulRajelli/robosimtools-mcp
cd robosimtools-mcp
npm install

Use it

The server talks over stdio, so any client that supports local MCP servers works. Replace the path below with wherever you cloned the repo.

Claude Desktop

Add to claude_desktop_config.json and restart:

{
  "mcpServers": {
    "robosimtools": {
      "command": "node",
      "args": ["ABSOLUTE/PATH/TO/robosimtools-mcp/src/index.js"]
    }
  }
}

OpenAI Codex CLI

Add to ~/.codex/config.toml and restart Codex:

[mcp_servers.robosimtools]
command = "node"
args = ["ABSOLUTE/PATH/TO/robosimtools-mcp/src/index.js"]

ChatGPT's own connectors target remote (HTTP) MCP servers — for this local stdio server, use the Codex CLI or Claude Desktop.

Then ask, e.g.: "Convert the quaternion (w=0.707, x=0, y=0, z=0.707) to URDF roll-pitch-yaw", or "Turn this STEP file into a URDF with computed inertia."

Test

npm test             # 39 known-answer checks across all 12 tools
npm run test:e2e     # connects a real MCP client over stdio
npm run test:install # packs, installs to a temp dir, drives the installed copy

test:install is the one that matters before a release: it verifies the published artifact — that the files allowlist is complete, the bin shebang works, and the lazily-imported OCCT WASM kernel still resolves once the package is inside someone else's node_modules.

Vendored modules

lib/ holds the tool logic — the same ES modules robosimtools.com serves at robosimtools.com/js/*.js. They are vendored (not fetched at runtime) so the package is self-contained. To refresh them from a local site checkout:

node scripts/sync-from-site.mjs /path/to/site/public/js

Design notes

• DOM in Node. Four tools (URDF validator, Xacro, MJCF, SDF converters) use the browser DOMParser/XMLSerializer. src/browser-globals.js provides those via linkedom so the modules run unchanged (its XMLSerializer strips the XML prolog linkedom adds, to match browsers).
• CAD kernel. robosim_step_to_urdf loads occt-import-js (a 7.6 MB WASM build of OpenCascade) lazily