twincat-mcp

Unofficial MCP server over the TwinCAT Automation Interface and ADS: build, deploy, read, and write.

Who it's for

An engineer attaching an MCP client to ADS, IEC 61131-3. Treat the write policy as the safety boundary: a gated write is still a write once you arm it.

Caveat / limitations

MIT. Not affiliated with Beckhoff. Wraps TcXaeShell and ADS so a client can build, read compile errors, deploy, run TcUnit, and read or write symbols. The README says dangerous operations need to be armed. Static analysis calls TE1200 and needs that license. This can change a target runtime. It is not TwinCAT CoAgent.

Protocols

ADSBeckhoff Automation Device Specification. TwinCAT runtimes expose symbols over ADS. Unofficial MCP servers that call ADS can build, deploy, and write symbols. That is a live controller, not a chat window.
IEC 61131-3The PLC programming-language standard: structured text, ladder, function block, and vendor dialects such as Siemens SCL and Rockwell structured text. This is a language family, not a field bus. A tool tagged here generates or explains controller code.

Sources

Repositoryhttps://github.com/eponce00/twincat-mcp

This page: https://otaihub.com/tools/twincat-mcp

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