Documentation MCP Server

Instructions

Search the docs for a given query and library.
Supports langchain, llama-index, and openai.

Args:
    query: The query to search for (e.g.: "Chroma DB").
    library: The library to search in. One of langchain, llama-index, openai.
    max_chars: Maximum characters to return (default: 1000 for free tier).

Returns:
    Text from the documentation.

Implementation Reference

• main.py:63-87 (handler)

  The handler function for the 'get_docs' tool. It searches documentation sites for specified libraries using web search and fetches relevant content, limiting to max_chars.

  @mcp.tool()
  async def get_docs(query: str, library: str, max_chars: int = 1000):
      """
      Search the docs for a given query and library.
      Supports langchain, llama-index, and openai.
  
      Args:
          query: The query to search for (e.g.: "Chroma DB").
          library: The library to search in. One of langchain, llama-index, openai.
          max_chars: Maximum characters to return (default: 1000 for free tier).
  
      Returns:
          Text from the documentation.
      """
      if library not in docs_urls:
          raise ValueError(f"Library {library} not supported. Supported libraries are: {', '.join(docs_urls.keys())}")
  
      url = f"site:{docs_urls[library]} {query}"
      results = await search_web(url)
      if len(results["organic"]) == 0:
          return "No results found."
      text = ""
      for result in results["organic"]:
          text += await fetch_url(result["link"])
      return text[:max_chars]  # Limit to max_chars characters

• main.py:24-43 (helper)

  Helper function to perform web search using Serper API, used by get_docs to find relevant doc pages.

  async def search_web(query: str) -> dict | None:
      """
      Search the web using the Serper API key for Google search, for the given query.
      """
      payload = json.dumps({"q": query, "num": 2})
      headers = {
          "X-API-KEY": os.getenv("SERPER_API_KEY"),
          "Content-Type": "application/json",       
      }
  
      async with httpx.AsyncClient() as client:
          try:
              response = await client.post(url=SERPER_URL, headers=headers, 
                                           data=payload, timeout=30.0)
              response.raise_for_status()
              return response.json()
          except httpx.TimeoutException:
              print("Timeout occurred while searching the web.")
              return {"organic": []}        

• main.py:45-62 (helper)

  Helper function to fetch and extract main text content from a URL, used by get_docs.

  async def fetch_url(url: str):
      """
      Fetch the content in the page of the URL using the Serper API key for Google search, 
      for the given query.
      """
      async with httpx.AsyncClient() as client:        
          try:
              response = await client.get(url=url, timeout=30.0)
              soup = BeautifulSoup(response.text, "html.parser")
              # text = soup.get_text()
              # return text
              # Target main content areas instead of all text
              main_content = soup.find("main") or soup.find("article") or soup
              text = main_content.get_text(separator="\n\n", strip=True)
              return text
          except httpx.TimeoutException:
              return "Timeout occurred while fetching the URL."

• main.py:14-18 (helper)

  Dictionary of supported library documentation site base URLs, used by get_docs.

  docs_urls = {
      "langchain": "python.langchain.com/docs",
      "llama-index": "docs.llamaindex.ai/en/stable",
      "openai": "platform.openai.com/docs",
  }

• main.py:63-63 (registration)

  Decorator that registers the get_docs function as an MCP tool.

  @mcp.tool()