lc2mcp

Overview

lc2mcp is a simple but powerful tool adapter that bridges the gap between LangChain's extensive tool ecosystem and the Model Context Protocol (MCP). It enables developers to expose existing LangChain tools to MCP clients like Claude and Cursor without rewriting the tools. The library converts LangChain tools to MCP-compatible formats automatically, handling Pydantic to JSON schema conversion, parameter descriptions, tool namespacing, and context injection.

Try asking AI

After installing, here are 4 things you can ask your AI assistant:

• get_weatherget_weather(city: str, unit: str = "celsius") -> str

  Get current weather for a city.

  Try:What's the weather like in London?Try:Get weather for Paris in celsius
• whoamiwhoami(runtime: ToolRuntime[UserContext]) -> str

  Return the current user.

  Try:Who am I?Try:Show user information
• process_dataprocess_data(data: str, mcp_ctx: Context) -> str

  Process data with progress reporting.

  Try:Process this datasetTry:Start data processing with progress updates
• DuckDuckGoSearchRun

  Perform a search using DuckDuckGo.

  Try:Search for latest AI newsTry:Find information about quantum computing
• WikipediaQueryRun

  Query Wikipedia for information.

  Try:Look up information about the solar systemTry:Find details about the history of Rome

Comparable tools

Installation

pip install lc2mcp

{
  "mcpServers": {
    "lc2mcp-example": {
      "command": "python",
      "args": ["-m", "fastmcp", "run", "/path/to/your/script.py"]
    }
  }
}

Compare lc2mcp with