added date validation code

app.py

@@ -11,28 +11,52 @@ from Gradio_UI import GradioUI
 
 # Below is an example of a tool that does nothing. Amaze us with your creativity !
 @tool
-def fetch_historical_price_data(symbol:str, start_date:str, end_date:str)-> pd.DataFrame: #it's import to specify the return type
-    #Keep this format for the description / args / args description but feel free to modify the tool
-    """Fetch daily historical stock price data for a given stock symbol from start_date to today 
+def fetch_historical_price_data(symbol: str, start_date: str, end_date: str) -> list[dict]:
+    """
+    Fetch daily historical stock price data for a given stock symbol between start_date and end_date. Use
+    toda=datetime.now() to confirm the dates are valid dates prior to calling the API.
+
     Args:
-        symbol: stock market symbol such as 'AAPL', 'MSFT', 'NVDA'
-        start_date: start date in YYYY-MM-DD format. Example - '2025-05-10'
-        end_date: end date in YYYY-MM-DD fomrat. Example '2025-11-03'
+        symbol: Stock market symbol such as 'AAPL', 'MSFT', 'NVDA'
+        start_date: Start date in 'YYYY-MM-DD' format
+        end_date: End date in 'YYYY-MM-DD' format
     """
-    FMP_KEY = os.getenv('FMP_KEY')
-    
-    url = f"https://financialmodelingprep.com/api/v3/historical-price-full/{symbol}?from={start_date}&to={end_date}&apikey={FMP_KEY}"
+    FMP_KEY = os.getenv("FMP_KEY")
+    if not FMP_KEY:
+        return [{"error": "Missing FMP_KEY environment variable"}]
+
+    # Validate and adjust date inputs
+    try:
+        start_dt = datetime.strptime(start_date, "%Y-%m-%d")
+        end_dt = datetime.strptime(end_date, "%Y-%m-%d")
+        today = datetime.now()
+        if end_dt > today:
+            end_dt = today
+            end_date = today.strftime("%Y-%m-%d")
+    except ValueError:
+        return [{"error": "Invalid date format. Use 'YYYY-MM-DD'."}]
+
+    url = (
+        f"https://financialmodelingprep.com/api/v3/historical-price-full/"
+        f"{symbol}?from={start_date}&to={end_date}&apikey={FMP_KEY}"
+    )
 
     try:
         response = requests.get(url)
         if response.status_code != 200:
-            return None
-        df = pd.DataFrame(response.json())
-        df['symbol'] = symbol
+            return [{"error": f"HTTP {response.status_code} from FMP API"}]
+
+        data = response.json().get("historical", [])
+        if not data:
+            return [{"message": f"No data available for {symbol} between {start_date} and {end_date}."}]
 
+        df = pd.DataFrame(data)
+        df["symbol"] = symbol
         return df.to_dict(orient="records")
+
     except requests.RequestException as e:
-        return f"Request failed for symbol {symbol}"
+        return [{"error": f"Request failed for {symbol}: {str(e)}"}]
+
 
 @tool
 def get_current_time_in_timezone(timezone: str) -> str: