MCP News Server

Instructions

Implementation Reference

• src/news_mcp/server.py:117-149 (handler)

  Handler function for calling the 'add-note' tool. It extracts name and content from arguments, stores the note in the global 'notes' dict, notifies clients of resource changes, and returns a confirmation message.

  @server.call_tool()
  async def handle_call_tool(
      name: str, arguments: dict | None
  ) -> list[types.TextContent | types.ImageContent | types.EmbeddedResource]:
      """
      Handle tool execution requests.
      Tools can modify server state and notify clients of changes.
      """
      if name != "add-note":
          raise ValueError(f"Unknown tool: {name}")
  
      if not arguments:
          raise ValueError("Missing arguments")
  
      note_name = arguments.get("name")
      content = arguments.get("content")
  
      if not note_name or not content:
          raise ValueError("Missing name or content")
  
      # Update server state
      notes[note_name] = content
  
      # Notify clients that resources have changed
      await server.request_context.session.send_resource_list_changed()
  
      return [
          types.TextContent(
              type="text",
              text=f"Added note '{note_name}' with content: {content}",
          )
      ]

• src/news_mcp/server.py:106-113 (schema)

  JSON Schema defining the input arguments for the 'add-note' tool: requires 'name' and 'content' as strings.

  inputSchema={
      "type": "object",
      "properties": {
          "name": {"type": "string"},
          "content": {"type": "string"},
      },
      "required": ["name", "content"],
  },

• src/news_mcp/server.py:103-114 (registration)

  Registration of the 'add-note' tool in the list_tools handler, including its name, description, and input schema.

  types.Tool(
      name="add-note",
      description="Add a new note",
      inputSchema={
          "type": "object",
          "properties": {
              "name": {"type": "string"},
              "content": {"type": "string"},
          },
          "required": ["name", "content"],
      },
  )