Work / GXBridge-MCP
GXBridge-MCP: GX Works3 MCP server — control Mitsubishi PLCs with AI
Control Mitsubishi GX Works3 and your PLC with AI — an MCP server for any agent
What is it made of?
gx-works3 · industrial-automation · mcp · mitsubishi-plc · model-context-protocol · plc
Source on GitHub ↗ · Need one like it? →
How does it work?
GXBridge turns Mitsubishi GX Works3 and a connected PLC into something you can simply talk to. It's a Model Context Protocol (MCP) server, so Claude — or any AI agent that speaks MCP — can open projects, write and build logic, download to the PLC, run/stop it, and read, write, and monitor live device values, all from plain natural language.
What you can do — just by asking
"Open my conveyor project and list all the program blocks and global labels."
"Write a Structured Text program: run the motor on Y0 when X0 is on and X1 is off, then build it."
"Read D100, and monitor X0–X7 and Y0–Y7 live while I test the panel."
"Compare this project against last week's backup and tell me what changed."
"Download the program to the PLC." — destructive operations require an explicit confirmation first.
Tool surface — 46 tools
Destructive operations — download, run/stop, delete, overwrite — require an explicit confirmation before they execute.
Remote engineering
GX Works3 only runs on Windows. GXBridge lets you work with it from a Mac, Linux, or another Windows machine as well.
Every programming mode
Whether your team works in Ladder Diagram, Structured Text, Function Block Diagram, or SFC, GXBridge creates projects in that language and authors logic for it — so AI assistance fits naturally into how you already engineer.
Why it matters
Industrial engineering tools are powerful but slow to operate by hand. GXBridge puts a capable AI in the driver's seat of that power: faster iteration, fewer repetitive clicks, easier onboarding, and a natural way to inspect, author, and test PLC programs — without giving up control or safety.
GXBridge is proprietary. This repository is an overview; the source is not public.
What do people ask about it?
Which Mitsubishi PLCs does GXBridge work with?
Any CPU GX Works3 programs — the MELSEC iQ-R, iQ-F (FX5U) and iQ-L families. GXBridge drives GX Works3 itself, Mitsubishi's MELSOFT engineering tool, so the PLC types, connection settings and download paths are the ones GX Works3 already supports; changing the PLC type of a project is one of its tools.
Is it read-only, or can the AI agent change the PLC?
It writes. The 46 tools cover authoring in Ladder Diagram, Structured Text, FBD and SFC, build and rebuild, PLCopen XML import and export, download to the PLC, run and stop, and live read, write and monitoring of device values. Every destructive operation — download, run/stop, delete, overwrite — needs an explicit confirmation before it executes, so an agent cannot do it by accident.
Which AI agents can use it?
Any client that speaks the Model Context Protocol: Claude Desktop and Claude Code, Cursor, or an agent of your own. GX Works3 only runs on Windows, but the agent can run on a Mac, on Linux or on another Windows machine and reach it from there.
Can logic be tested before it reaches a real CPU?
Yes. Simulator control sits next to online status and live monitoring in the tool surface, so a program can be built and exercised in the GX Works3 simulator, then downloaded to the PLC once it behaves.
Is GXBridge open source?
No. The GitHub repository is an overview; the source is proprietary. Ask through the contact page about using it on your line.
What else did I build?
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