Snap7

MCP server for python-snap7, enabling MCP clients to interact with Siemens PLCs

PyPI Python Coverage Ruff

Install

pip install mcp-snap7

Requirements

• python-snap7 requires the libsnap7 library to be installed on your system. See python-snap7 documentation for installation instructions.

Usage

As MCP Server

Configure your MCP client to use mcp-snap7 as a stdio server:

{
  "mcpServers": {
    "mcp-snap7": {
      "command": "mcp-snap7"
    }
  }
}

Available Tools

• connect_plc - Connect to a Siemens PLC
• disconnect_plc - Disconnect from PLC
• get_connected - Check connection status
• db_read / db_write - Read/write data blocks
• mb_read / mb_write - Read/write memory bytes
• tm_read / tm_write - Read/write timers
• ct_read / ct_write - Read/write counters
• eb_read / eb_write - Read/write edge inputs
• ab_read / ab_write - Read/write absolute bytes
• get_cpu_info - Get CPU information
• get_cpu_state - Get CPU state
• get_protection - Get PLC protection level
• plc_cold_start - Trigger cold start
• plc_hot_start - Trigger hot start
• plc_stop - Stop PLC
• get_error_text - Get error description

Development

git clone https://github.com/daedalus/mcp-snap7.git
cd mcp-snap7
pip install -e ".[test]"

# run tests
pytest

# format
ruff format src/ tests/

# lint
ruff check src/ tests/

# type check
mypy src/