Update agent.py

Saving query history.

agent.py

@@ -58,7 +58,8 @@ def create_assistant_tools(cfg):
         summary_num_results = 10,
         vectara_summarizer = summarizer,
         include_citations = True,
-        vectara_prompt_text=prompt
+        vectara_prompt_text=prompt,
+        save_history = True
     )
 
     tools_factory = ToolsFactory()