MCP Yahoo Finance

Instructions

Implementation Reference

• src/mcp_yahoo_finance/server.py:155-162 (handler)

  The core handler function that fetches the latest news for a given stock symbol using yfinance's Ticker.news property and serializes it to JSON.

  def get_news(self, symbol: str) -> str:
      """Get news for a given stock symbol.
  
      Args:
          symbol (str): Stock symbol in Yahoo Finance format.
      """
      stock = Ticker(ticker=symbol, session=self.session)
      return json.dumps(stock.news, indent=2)

• src/mcp_yahoo_finance/server.py:231-231 (registration)

  Registers the 'get_news' tool in the MCP server's list_tools() by wrapping the handler function with generate_tool, which also generates the input schema from the function signature and docstring.

  generate_tool(yf.get_news),

• src/mcp_yahoo_finance/server.py:264-266 (handler)

  Dispatches execution of the 'get_news' tool call to the underlying YahooFinance.get_news handler and formats the result as MCP TextContent.

  case "get_news":
      price = yf.get_news(**args)
      return [TextContent(type="text", text=price)]

• src/mcp_yahoo_finance/utils.py:31-65 (helper)

  Helper function used to generate the Tool schema (including input schema) for get_news and other tools from Python function introspection and docstring parsing.

  def generate_tool(func: Any) -> Tool:
      """Generates a tool schema from a Python function."""
      signature = inspect.signature(func)
      docstring = inspect.getdoc(func) or ""
      param_descriptions = parse_docstring(docstring)
  
      schema = {
          "name": func.__name__,
          "description": docstring.split("Args:")[0].strip(),
          "inputSchema": {
              "type": "object",
              "properties": {},
          },
      }
  
      for param_name, param in signature.parameters.items():
          param_type = (
              "number"
              if param.annotation is float
              else "string"
              if param.annotation is str
              else "string"
          )
          schema["inputSchema"]["properties"][param_name] = {
              "type": param_type,
              "description": param_descriptions.get(param_name, ""),
          }
  
          if "required" not in schema["inputSchema"]:
              schema["inputSchema"]["required"] = [param_name]
          else:
              if "=" not in str(param):
                  schema["inputSchema"]["required"].append(param_name)
  
      return Tool(**schema)