Specify CUSTOM_PROMPT to improve answer reproducibility

app.py

@@ -21,6 +21,18 @@ from youtube_transcript_tool import YoutubeTranscriptTool
 # --- Constants ---
 DEFAULT_API_URL = "https://agents-course-unit4-scoring.hf.space"
 
+CUSTOM_PROMPT = """
+    You are a general AI assistant. I will ask you a question.
+    Your final response must be ONLY the answer itself and nothing else.
+    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 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".
+"""
+
 rate_limiter = RateLimiter()
 
 # --- Basic Agent Definition ---
@@ -43,6 +55,7 @@ class BasicAgent:
             model=model,
             step_callbacks=[rate_limiter.increment_and_sleep_if_needed],
             additional_authorized_imports=["pandas"],
+            instructions=CUSTOM_PROMPT
         )
         print("BasicAgent initialized.")