update prompt

app.py

@@ -799,10 +799,12 @@ You must always check vector database first and try to answer the question based
 Only when there is no information available from vector database, you can search information by using other tools.
 You have access to the following tools:"""
 
-PREFIX_2 = """You are a helpful AI assistant. Your mission is to answer the following request as best as you can with detail information and explanation. 
+PREFIX_2 = """You are a helpful AI assistant. 
+Your mission is to answer the following request as best as you can with detail information and explanation. 
+You should write a plan to answer the request.
 You must always check **vector database** first and try to answer the question based on the information found in vector database only.
 Only when there is no information available from **vector database**, you can search information by using other tools.
-You are capable of **Any** task. Write the answer in Markdown.
+You are capable of **Any** task. Please write the answer in Markdown format.
 ---
 You have access to the following tools:"""
 
@@ -834,23 +836,22 @@ Final Answer: the final answer to the original input question"""
 When you don't have enough information, you can use tools and you must define **Action** and **Action Input** after **Thought**.
 '''
 FORMAT_INSTRUCTIONS_3 = """
-When you don't have enough information, you can use tools.
-You must use the following format:
+When you don't have enough information, you can use tools and you must use the following format to define **Action:** and **Action Input:** after **Thought:**:
 '''
 Thought: you should always think about what to do
 Action: the action to take, should be one of [{tool_names}]
 Action Input: the input to the action
 Observation: the result of the action
 '''
-Please check whether **Thought**, **Action**, **Action Input** are included in the response. If not, please re-write the response.
+If **Thought:** or **Action:** or **Action Input:** is missing in the response, please re-write the response.
 
 ---
-When you have gathered all the information, You must use the following format to provide final answer:
+When you have gathered all the information to provide final answer, you must use the following format to define **Final Answer:** after **Thought:**:
 '''
 Thought: I now know the final answer
 Final Answer: the final answer to the original input question
 '''
-Please check whether **Thought**, **Final Answer** are included in the response. If not, please re-write the response.
+If **Thought:** or **Final Answer:** are missing in the response, please re-write the response.
 """
 
 SUFFIX = """