kc_modbus_mcp

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正體中文

Look, nobody wants to memorize that register 40001 is the temperature sensor. Life is too short and Modbus addresses are too many. This is an MCP Server for Modbus TCP devices -- you define device profiles in YAML, and then AI agents can read/write PLC registers by name like civilized beings.

It also ships with a built-in simulator, because we all know you don't have a PLC sitting on your desk. (And if you do, please dust it off.)

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I kept looking at existing MCP servers for Modbus and kept finding the same four disappointments:

1. No semantic register mapping -- the AI has to know raw addresses like 40001. Asking it to "read temperature" gets you a blank stare.
2. No data type conversion -- everything comes back as raw uint16, because apparently float32 is too fancy.
3. No built-in simulator -- want to test? Go buy hardware. Or beg a colleague. Or stare at the ceiling.
4. No device profiles -- no way to pre-configure connection details and register maps, so you get to type the same host/port/slave_id over and over like it's 1998.

So I did the unreasonable thing and fixed all four myself.

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User (CLI / Chat / OpenClaw)
  → AI Agent (Claude / OpenClaw / etc.)
    → MCP Protocol (Streamable HTTP)
      → kc_modbus_mcp (FastMCP Server)
        → Profile Manager (YAML device profiles)
        → pymodbus (async Modbus TCP client)
      → Modbus TCP Device / Built-in Simulator

• Natural language control -- "read the factory temperature" just works. No a