Fix chunk jumping

backend/app.py

@@ -195,12 +195,12 @@ async def chat_stream(request: ChatRequest):
     print(f"include_document: {include_document} (messages: {len(request.messages)}, action: {action})")
     print(f"current_chunk: {current_chunk[:100] if current_chunk else 'None'}")
     print(f"next_chunk: {next_chunk[:100] if next_chunk else 'None'}")
+    print(f"user_goal: {user_goal if user_goal else 'None'}")
     if is_transition:
         system_prompt = TRANSITION_PROMPT_TEMPLATE.format(
             action=action,
             current_chunk=current_chunk,
             next_chunk=next_chunk,
-            document=document
         )
         print(f"Transition system prompt: {system_prompt[:200]}...")
     else:
@@ -230,8 +230,14 @@ async def chat_stream(request: ChatRequest):
             if msg.role in ["user", "assistant"]
         ]
         print(anthropic_messages)
-        # For transitions, add a dummy user message to trigger Claude response
-        if not any(msg["role"] == "user" for msg in anthropic_messages):
+        
+        # Ensure the conversation ends with a user message for thinking mode
+        if anthropic_messages and anthropic_messages[-1]["role"] == "assistant":
+            if is_transition:
+                anthropic_messages.append({"role": "user", "content": "Please continue to the next section."})
+            else:
+                anthropic_messages.append({"role": "user", "content": "Please continue."})
+        elif not any(msg["role"] == "user" for msg in anthropic_messages):
             if is_transition:
                 anthropic_messages.append({"role": "user", "content": "Please continue to the next section."})
             else:

backend/prompts/transition_prompt.txt

@@ -3,7 +3,6 @@ The user has just chosen to "{action}" the previous section and is moving to a n
 
 Previous Section: {current_chunk}
 New Section: {next_chunk}
-Full Document: {document}
 
 TRANSITION INSTRUCTIONS:
 
@@ -26,4 +25,5 @@ TRANSITION INSTRUCTIONS:
 - Maintain momentum - this is a continuation, not a restart
 - Stay focused on phenomenological understanding and observables
 
-Start by acknowledging their {action} choice, then smoothly transition to introducing the new section and begin your first question about {next_chunk}.
+Start by acknowledging their {action} choice, then smoothly transition to introducing the new section and begin your first question about {next_chunk}. Don't get ahead of yourself, and adapt the difficulty of your questions based on the user's previous answers.
+Also, don't ask questions about material that you haven't talked about.