NASA-MCP

Instructions

Implementation Reference

• src/nasa_mcp/server.py:86-150 (handler)

  Handler function implementing the get_astronomy_picture_of_day tool. It queries the NASA APOD API, handles responses, and formats the output as text.
  @mcp.tool() async def get_astronomy_picture_of_day(date: str = None, count: int = None, thumbs: bool = False) -> str: """Get NASA's astronomy picture of the day. Args: date: Date of the image in YYYY-MM-DD format. If not specified, the current date is used. count: If specified, returns 'count' random images. Cannot be used with 'date'. thumbs: If True, returns the thumbnail URL for videos. If APOD is not a video, this parameter is ignored. """ params = {} if date: params["date"] = date if count: params["count"] = count if thumbs: params["thumbs"] = "true" url = f"{NASA_API_BASE}/planetary/apod" data = await make_nasa_request(url, params) if not data: return "Could not retrieve astronomy picture of the day data due to a connection error." # Check for error response (must be a dictionary) if isinstance(data, dict) and "error" in data: return f"API Error: {data.get('error')} - Details: {data.get('details', 'N/A')}" if isinstance(data, dict) and data.get("binary_content"): # APOD URL itself might point to an image, but the API response should be JSON return f"Received unexpected binary content from APOD API. URL: {data.get('url')}" try: # If count is specified, data will be a list if isinstance(data, list): result = [] for item in data: result.append(f"Date: {item.get('date', 'Unknown')}") result.append(f"Title: {item.get('title', 'No title')}") result.append(f"Explanation: {item.get('explanation', 'No explanation')}") result.append(f"URL: {item.get('url', 'Not available')}") if 'copyright' in item: result.append(f"Copyright: {item.get('copyright', 'Unknown')}") if thumbs and 'thumbnail_url' in item: result.append(f"Thumbnail URL: {item.get('thumbnail_url', 'Not available')}") result.append("-" * 40) return "n".join(result) else: # If it's a single image result = f""" Date: {data.get('date', 'Unknown')} Title: {data.get('title', 'No title')} Explanation: {data.get('explanation', 'No explanation')} URL: {data.get('url', 'Not available')} """ if 'copyright' in data: result += f"Copyright: {data.get('copyright', 'Unknown')}n" if thumbs and 'thumbnail_url' in data: result += f"Thumbnail URL: {data.get('thumbnail_url', 'Not available')}n" return result except Exception as e: logger.error(f"Error processing APOD data: {str(e)}") return f"Error processing astronomy picture data: {str(e)}"
• src/nasa_mcp/server.py:28-83 (helper)

  Shared helper function used by get_astronomy_picture_of_day (and other tools) to make HTTP requests to NASA APIs, handling JSON, binary images, and errors.
  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:86-86 (registration)

  The @mcp.tool() decorator registers the get_astronomy_picture_of_day function as an MCP tool.
  @mcp.tool()