MCP

OpenMotoko supports the Model Context Protocol in both directions: as a client connecting to external MCP servers, and as a server exposing its own tools.

MCP client

Connect OpenMotoko to external MCP servers to give the agent access to third-party tools.

Configuration

Add servers to openmotoko.json under the mcp key:

{
  "mcp": {
    "servers": [
      {
        "id": "filesystem",
        "name": "Local Files",
        "transport": "stdio",
        "command": "npx",
        "args": ["-y", "@modelcontextprotocol/server-filesystem", "/home/user/docs"]
      },
      {
        "id": "weather",
        "name": "Weather API",
        "transport": "http",
        "url": "https://mcp.example.com/weather"
      }
    ]
  }
}

Transport types

Transport	Field	Description
stdio	command, args	Spawns a local process, communicates over stdin/stdout
http	url	Connects to a remote StreamableHTTP endpoint

Environment variables

Pass environment variables to stdio servers:

{
  "id": "github",
  "transport": "stdio",
  "command": "npx",
  "args": ["-y", "@modelcontextprotocol/server-github"],
  "env": {
    "GITHUB_TOKEN": "ghp_..."
  }
}

Tool namespacing

External tools are namespaced as mcp_{serverId}_{toolName} to avoid conflicts. For example, a tool called search from a server with ID docs becomes mcp_docs_search.

MCP server

Expose OpenMotoko’s tools to other MCP clients.

Enable

Set expose: true in the MCP config:

{
  "mcp": {
    "expose": true
  }
}

This starts an MCP server over stdio transport using the @modelcontextprotocol/sdk. All enabled skill tools are registered and available to connecting clients.

Use cases

• Connect Claude Desktop or other MCP clients to OpenMotoko
• Chain multiple AI agents, each accessing the other’s tools
• Build workflows where one system delegates tasks to OpenMotoko

Full config reference

{
  "mcp": {
    "servers": [
      {
        "id": "string (required)",
        "name": "string (optional display name)",
        "transport": "stdio | http",
        "command": "string (stdio only)",
        "args": ["string[]", "(stdio only)"],
        "url": "string (http only)",
        "env": { "KEY": "VALUE" }
      }
    ],
    "expose": false
  }
}