NASA-MCP

Instructions

Implementation Reference

• src/nasa_mcp/server.py:750-808 (handler)

  Main handler function for the 'get_earth_imagery' tool. Fetches imagery from NASA's Earth imagery API endpoint, handles parameters like lat, lon, date, dim, and cloud_score. Uses make_nasa_request helper and processes both JSON metadata and potential binary image responses.
  async def get_earth_imagery(lat: float, lon: float, date: str = None, dim: float = 0.025, cloud_score: bool = False) -> str: """Get Earth imagery from Landsat 8 satellite. Args: lat: Latitude. lon: Longitude. date: Image date in YYYY-MM-DD format. If not specified, the most recent image is used. dim: Width and height of the image in degrees (0.025 degrees is approximately 2.7 km). cloud_score: Calculate the percentage of the image covered by clouds (currently not available). """ params = { "lat": lat, "lon": lon, "dim": dim } if date: params["date"] = date # cloud_score parameter seems deprecated or unavailable based on docs # if cloud_score: # params["cloud_score"] = "True" url = f"{NASA_API_BASE}/planetary/earth/imagery" data = await make_nasa_request(url, params) if not data: return "Could not retrieve Earth imagery due to a connection error." # Check for error response (must be a dictionary) if isinstance(data, dict) and "error" in data: # Handle specific case where API returns error message instead of image/JSON if isinstance(data.get("details"), str) and "No Landsat 8 imagery available" in data["details"]: return f"No Landsat 8 imagery available for the specified location and date (Lat: {lat}, Lon: {lon}, Date: {date or 'latest'})." return f"API Error: {data.get('error')} - Details: {data.get('details', 'N/A')}" # Handle binary content if isinstance(data, dict) and data.get("binary_content"): # The API returned the image directly return f"Received image data directly ({data.get('content_type')}). Cannot display image content, but the image is available at the requested URL: {data.get('url')}" # If it's not binary, it should be JSON containing the URL try: result = [ f"Earth image metadata for coordinates: Lat {lat}, Lon {lon}", f"Date: {data.get('date', 'Unknown')}", f"ID: {data.get('id', 'Unknown')}", f"Image URL: {data.get('url', 'Not available')}" # This URL should point to the image ] # Cloud score might be present in JSON even if binary isn't returned if 'cloud_score' in data and data['cloud_score'] is not None: # Check for None explicitly result.append(f"Cloud score: {data.get('cloud_score')}") else: result.append("Cloud score: Not available") return "n".join(result) except Exception as e: logger.error(f"Error processing Earth Imagery JSON data: {str(e)}") return f"Error processing Earth imagery data: {str(e)}"
• src/nasa_mcp/server.py:28-83 (helper)

  Shared helper function used by get_earth_imagery (and other tools) to make HTTP requests to NASA APIs, handling JSON parsing, binary image detection, errors, and API key injection.
  async def make_nasa_request(url: str, params: dict = None) -> Union[dict[str, Any], List[Any], None]: """Make a request to the NASA API with proper error handling. Handles both JSON and binary (image) responses. """ logger.info(f"Making request to: {url} with params: {params}") if params is None: params = {} # Ensure API key is included in parameters if "api_key" not in params: params["api_key"] = API_KEY async with httpx.AsyncClient() as client: try: response = await client.get(url, params=params, timeout=30.0, follow_redirects=True) response.raise_for_status() # Raise an exception for bad status codes (4xx or 5xx) content_type = response.headers.get("Content-Type", "").lower() if "application/json" in content_type: try: return response.json() except json.JSONDecodeError as json_err: logger.error(f"JSON decode error for URL {response.url}: {json_err}") logger.error(f"Response text: {response.text[:500]}") # Log beginning of text return {"error": "Failed to decode JSON response", "details": str(json_err)} elif content_type.startswith("image/"): logger.info(f"Received binary image content ({content_type}) from {response.url}") # Return a dictionary indicating binary content was received return { "binary_content": True, "content_type": content_type, "url": str(response.url) # Return the final URL after redirects } else: # Handle other unexpected content types logger.warning(f"Unexpected content type '{content_type}' received from {response.url}") return {"error": f"Unexpected content type: {content_type}", "content": response.text[:500]} except httpx.HTTPStatusError as http_err: logger.error(f"HTTP error occurred: {http_err} - {http_err.response.status_code} for URL {http_err.request.url}") try: # Try to get more details from response body if possible error_details = http_err.response.json() except Exception: error_details = http_err.response.text[:500] return {"error": f"HTTP error: {http_err.response.status_code}", "details": error_details} except httpx.RequestError as req_err: logger.error(f"Request error occurred: {req_err} for URL {req_err.request.url}") return {"error": "Request failed", "details": str(req_err)} except Exception as e: logger.error(f"An unexpected error occurred: {str(e)}") return {"error": "An unexpected error occurred", "details": str(e)}
• src/nasa_mcp/server.py:750-750 (registration)

  The @mcp.tool() decorator registers the get_earth_imagery function as an MCP tool in the FastMCP server.
  async def get_earth_imagery(lat: float, lon: float, date: str = None, dim: float = 0.025, cloud_score: bool = False) -> str:
• src/nasa_mcp/server.py:752-759 (schema)

  Input schema/arguments and description defined in the function docstring, used by FastMCP for tool schema generation.
  Args: lat: Latitude. lon: Longitude. date: Image date in YYYY-MM-DD format. If not specified, the most recent image is used. dim: Width and height of the image in degrees (0.025 degrees is approximately 2.7 km). cloud_score: Calculate the percentage of the image covered by clouds (currently not available). """