LibraLM MCP Server

Instructions

Implementation Reference

• libralm_mcp_server.py:168-175 (handler)

  The handler function implementing the 'get_book_details' tool. It fetches detailed book information from the LibraLM API using the provided book_id and returns a structured BookInfo object.

  @mcp.tool()
  def get_book_details(book_id: str) -> BookInfo:
      """Get detailed information about a specific book"""
      try:
          data = _make_api_request(f"/books/{book_id}")
          return BookInfo(**data)
      except Exception as e:
          raise ValueError(f"Error getting details for book '{book_id}': {str(e)}")

• libralm_mcp_server.py:86-101 (schema)

  Pydantic model defining the output schema (BookInfo) for the get_book_details tool.

  class BookInfo(BaseModel):
      """Book information structure"""
  
      book_id: str
      title: str
      author: Optional[str] = None
      category: Optional[str] = None
      subtitle: Optional[str] = None
      summary: Optional[str] = None
      length: Optional[str] = None
      release_date: Optional[str] = None
      tier: Optional[str] = None
      has_summary: bool
      has_chapter_summaries: bool
      has_table_of_contents: bool

• libralm_mcp_server.py:103-127 (helper)

  Core helper function used by the tool to perform authenticated GET requests to the LibraLM API endpoints.

  def _make_api_request(endpoint: str) -> dict:
      """Make an authenticated request to the LibraLM API"""
      # Get API key and base URL from request context or environment
      api_key = get_api_key()
      base_url = get_api_base_url()
  
      headers = {"x-api-key": api_key, "Content-Type": "application/json"}
  
      url = f"{base_url}{endpoint}"
      response = requests.get(url, headers=headers)
  
      if response.status_code == 401:
          raise ValueError("Invalid API key. Please check your LibraLM API key.")
      elif response.status_code == 404:
          raise ValueError(f"Resource not found: {endpoint}")
      elif response.status_code != 200:
          raise ValueError(
              f"API request failed with status {response.status_code}: {response.text}"
          )
  
      # Handle wrapped response format from Lambda
      result = response.json()
      if isinstance(result, dict) and "data" in result:
          return result["data"]
      return result

• libralm_mcp_server.py:168-168 (registration)

  FastMCP decorator that registers the get_book_details function as a tool.

  @mcp.tool()