diff --git a/mind_palace/app.py b/mind_palace/app.py
index 0d01673..5261cae 100644
--- a/mind_palace/app.py
+++ b/mind_palace/app.py
@@ -3,11 +3,15 @@
 import openai
 import streamlit as st
 import welcome
+from itune import MultiArmedBandit, Tune
 from llama_index.query_engine import CitationQueryEngine
 
 openai.api_key = st.secrets.openai_key
 xml_dir = "./resources/xmls/dennis-oct-10/"
 gpt_model = "gpt-3.5-turbo"
+itune = Tune(strategy=MultiArmedBandit())
+
+itune.load()
 
 st.set_page_config(page_title="Q&A with Dennis's PDFs")
 st.title("Q&A with Dennis's PDFs 💬")
@@ -28,7 +32,11 @@ def load_nodes_and_index(xml_dir, model):
 
 
 nodes, vector_index = load_nodes_and_index(xml_dir, gpt_model)
-query_engine = CitationQueryEngine.from_args(index=vector_index, verbose=True)
+query_engine = CitationQueryEngine.from_args(
+    index=vector_index,
+    similarity_top_k=itune.choose(similarity_top_k=[3, 5]),
+    verbose=True,
+)
 
 
 @st.cache_data(
@@ -54,21 +62,34 @@ def get_welcome_message(abstracts):
             "content": "Ask me a question about these papers.",
         },
     ]
-else:
+# if this refresh is not triggered by user button press, reset the chat messages
+elif not st.session_state.rating_button_pressed:
+    print("clearing chat messages!")
     st.session_state.messages = []
 
+# this needs to be reset after checking if the messaages should be cleared
+st.session_state.rating_button_pressed = False
 
 if prompt := st.chat_input(
     "Your question"
 ):  # Prompt for user input and save to chat history
     st.session_state.messages.append({"role": "user", "content": prompt})
 
+
 for message in st.session_state.messages:  # Display the prior chat messages
     with st.chat_message(message["role"]):
         st.write(message["content"])
 
-# If last message is not from assistant, generate a new response
-if st.session_state.messages[-1]["role"] != "assistant":
+
+def user_clicked_rating(is_good_response):
+    print(f"user thumbs {'up' if is_good_response else 'down'}")
+    itune.register_outcome(is_good_response)
+    itune.save()
+    st.session_state.rating_button_pressed = True
+
+
+# If last message is from user, generate a new response
+if st.session_state.messages[-1]["role"] == "user":
     with st.chat_message("assistant"):
         with st.spinner("Thinking..."):
             response = query_engine.query(prompt)
@@ -77,6 +98,24 @@ def get_welcome_message(abstracts):
             message = {"role": "assistant", "content": response.response}
             st.session_state.messages.append(message)  # Add response to message history
 
+            _, col1, col2 = st.columns([7, 1, 1], gap="small")
+            col1.button(
+                "👍",
+                on_click=user_clicked_rating,
+                args=[True],
+                help="Good response",
+                key="good_response",
+                use_container_width=True,
+            )
+            col2.button(
+                "👎",
+                on_click=user_clicked_rating,
+                args=[False],
+                help="Bad response",
+                key="bad_response",
+                use_container_width=True,
+            )
+
             st.markdown("### Sources")
             for i, source_node in enumerate(response.source_nodes):
                 with st.expander(f"[{i + 1}] {source_node.node.metadata['citation']}"):
diff --git a/requirements/build.txt b/requirements/build.txt
index ce83e11..ca7bc9e 100644
--- a/requirements/build.txt
+++ b/requirements/build.txt
@@ -1,3 +1,4 @@
+itune==0.1.1
 pypdf==3.16.0
 grobid-tei-xml==0.1.3
 nltk==3.8.1