The README is unusually specific about one trap: launched via `npx` inside a host like Claude Desktop, the process inherits a `PATH` that breaks an internal CODESYS call and you get `'C:\Program' is not recognized` the moment you connect. Configure `"command": "codesys-mcp-tool"` instead. The other rule that saves an afternoon: use forward slashes in the object paths you pass to tools.
An MCP server for CODESYS V3 industrial programming environments. It drives the CODESYS Scripting Engine, so project management, POU creation, code editing and compilation become tool calls from an assistant rather than clicks in the IDE.
- Projects: `open_project` for an existing one, `create_project` from a standard template, `save_project`
- POUs: `create_pou` for Programs, Function Blocks and Functions, and `set_pou_code` for declaration and implementation text
- Function Block members: `create_property` and `create_method`
- `compile_project`, so the assistant finds out whether its edit builds
- Read-only resources: `codesys://project/status` for scripting state and the currently open project, `codesys://project/{+project_path}/structure` for the object tree, and `codesys://project/{+project_path}/pou/{+pou_path}/code` for a POU, method or property accessor's code
A CODESYS V3 installation with the Scripting Engine component enabled at install time — the toolkit was tested against 3.5 SP21 — and Node.js 18.0.0 or later. Install globally with `npm install -g @codesys/mcp-toolkit`, then point your client at the `codesys-mcp-tool` command and pass `--codesys-path` to your `CODESYS.exe` and `--codesys-profile` to the exact profile name; `--workspace` sets the root for relative project paths. CODESYS uses Python 2.7 internally for scripting, but the toolkit handles that — you do not manage it.
One command — npm install -g @codesys/mcp-toolkit