improve custom prompt

app.py

@@ -28,12 +28,14 @@ CUSTOM_PROMPT = """
     Do not include any explanations, reasoning, or prefixes like "FINAL ANSWER:".
     
     The answer should be a number OR as few words as possible OR a comma separated list.
-    - If the answer is a number, do not use commas for thousands separators (e.g., write 1000 not 1,000) and do not include units like '$' or '%' unless specified.
+    - If the answer is a number, do not use commas for thousands separators
+        (e.g., write 1000 not 1,000) and do not include units like '$' or '%' unless specified.
     - If the answer is a string, do not use articles (a, an, the) or abbreviations.
     - If the answer is a list, apply these rules to each element 
-        and separete them with a comma like "a, b, c".
+        and separete them with a comma and a whitespace like "a, b, c" not "a,b,c".
 
     Attached files can be downloaded via the Internet.
+    When downloading files, try to download them in python code before visiting the website.
 """
 
 rate_limiter = RateLimiter()