Slim MCP

Instructions

Implementation Reference

• src/claude_tools/weather.py:33-42 (handler)

  The main handler function for the 'get_alerts' tool. It fetches active weather alerts for a given US state from the National Weather Service API, processes the response, formats each alert using the 'format_alert' helper, and returns a concatenated string of formatted alerts.
  async def get_alerts(state: str) -> str: """Get weather alerts for a US state.""" url = f"{NWS_API_BASE}/alerts/active/area/{state}" data = await make_nws_request(url) if not data or "features" not in data: return "Unable to fetch alerts or no alerts found." if not data["features"]: return "No active alerts for this state." alerts = [format_alert(feature) for feature in data["features"]] return "\n---\n".join(alerts)
• src/claude_tools/weather.py:71-75 (registration)

  Registers the 'get_alerts' tool (along with 'get_forecast') using the MCP 'mcp.tool()' decorator within the register_weather_tools function.
  def register_weather_tools(mcp): """Register all weather tools with the MCP server.""" mcp.tool()(get_alerts) mcp.tool()(get_forecast)
• src/claude_tools/weather.py:22-31 (helper)

  Helper function specifically used by 'get_alerts' to format individual alert features from the API response into a human-readable multi-line string.
  def format_alert(feature: dict) -> str: """Format an alert feature into a readable string.""" props = feature["properties"] return f""" Event: {props.get('event', 'Unknown')} Area: {props.get('areaDesc', 'Unknown')} Severity: {props.get('severity', 'Unknown')} Description: {props.get('description', 'No description available')} Instructions: {props.get('instruction', 'No specific instructions provided')} """
• src/claude_tools/weather.py:8-20 (helper)

  Shared helper function used by 'get_alerts' (and 'get_forecast') to make asynchronous HTTP requests to the National Weather Service API with proper headers, timeout, and error handling.
  async def make_nws_request(url: str) -> dict[str, Any] | None: """Make a request to the NWS API with proper error handling.""" headers = { "User-Agent": USER_AGENT, "Accept": "application/geo+json" } async with httpx.AsyncClient() as client: try: response = await client.get(url, headers=headers, timeout=30.0) response.raise_for_status() return response.json() except Exception: return None