Update app.py

app.py

@@ -96,6 +96,7 @@ def build_system_prompt(language: str, conversation_summary: str, mode: str) ->
         base += (
             "You are in STUDENT MODE: Your goal is to engage the user ONLY in programming, coding, "
             "and problem-solving tasks.\n"
+            "Do NOT give complete answers or full code.\n"
             "Do NOT answer general knowledge, personal, or unrelated questions.\n"
             "Instead:\n"
             " - Ask guiding questions to make the user think about coding problems.\n"