MCP Server¶

The Model Context Protocol (MCP) server exposes Adsify’s PLC capabilities to AI assistants. Instead of manually constructing API calls, users can interact with PLCs through natural language — asking an AI assistant to read variables, browse symbols, or check EtherCAT health.

Endpoint¶

Endpoint: MCP Endpoint API_MCP_ENDPOINT

status: implemented

component: Mcp

method: MCP

route: /mcp

policy: ReadAccess

implements: FEAT_MCP, REQ_MCP_AUTH, REQ_MCP_FEATURE_GATE, REQ_MCP_PLC_ACCESS

Model Context Protocol server endpoint. Enforces the ReadAccess policy; the write_variable tool enforces WriteAccess internally.

Transport: Streamable HTTP with SSE fallback.

Feature Flag¶

The MCP server is disabled by default. Enable it in configuration:

{
  "Features": {
    "Mcp": { "Enabled": true }
  }
}

Authentication¶

The MCP endpoint uses the same authentication as the REST API:

Production: JWT Bearer token required. The /mcp endpoint enforces the ReadAccess policy. The write_variable tool enforces WriteAccess internally.
Development: When no Authority is configured, authentication is bypassed.

Tools¶

The tools are specified in MCP Tools (SPEC_MCP_TOOLS).

Tool	Description	Auth
`list_plcs`	List all configured PLCs with connection status	ReadAccess
`get_plc_status`	Get connection state and device info for a PLC	ReadAccess
`read_variable`	Read a PLC variable by symbol path	ReadAccess
`read_variables`	Batch read multiple variables	ReadAccess
`write_variable`	Write a value to a PLC variable	WriteAccess
`browse_symbols`	List/search symbols at a path or by pattern	ReadAccess
`get_symbol_info`	Get detailed type info for a symbol	ReadAccess
`get_device_info`	Get PLC device name, version, state	ReadAccess
`get_ethercat_health`	Get EtherCAT master state and slave summary	ReadAccess
`get_ethercat_slave`	Get detailed info for a specific EtherCAT slave	ReadAccess

Resources¶

The resources are specified in MCP Resources (SPEC_MCP_RESOURCES).

Resource URI	Description
`adsify://plcs`	List of all PLCs with status
`adsify://plcs/{plcId}/state`	Current PLC device state
`adsify://plcs/{plcId}/symbols`	Root-level symbol tree
`adsify://plcs/{plcId}/ethercat/health`	EtherCAT diagnostics summary

Client Configuration¶

Claude Code¶

claude mcp add --transport http --scope user adsify http://localhost:5000/mcp

Claude Desktop¶

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "adsify": {
      "type": "http",
      "url": "http://localhost:5000/mcp",
      "headers": {
        "Authorization": "Bearer <jwt-token>"
      }
    }
  }
}

VS Code (GitHub Copilot)¶

Add to .vscode/mcp.json:

{
  "servers": {
    "adsify": {
      "type": "http",
      "url": "http://localhost:5000/mcp",
      "headers": {
        "Authorization": "Bearer <jwt-token>"
      }
    }
  }
}

In development mode (no Authority configured), no Authorization header is needed.

Example Prompts¶

Once connected, try asking your AI assistant:

“Is the PLC running? What’s the current state?”
“Read all motor parameters and tell me if anything looks abnormal”
“What symbols are available under GVL?”
“Show me the EtherCAT slave health – are any in error state?”