Update model.py

model.py

@@ -183,13 +183,28 @@ def build_graph(provider: str = "groq"):
         """Assistant node"""
         return {"messages": [llm_with_tools.invoke(state["messages"])]}
     
+    # def retriever(state: MessagesState):
+    #     """Retriever node"""
+    #     similar_question = vector_store.similarity_search(state["messages"][0].content)
+    #     example_msg = HumanMessage(
+    #         content=f"Here I provide a similar question and answer for reference: \n\n{similar_question[0].page_content}",
+    #     )
+    #     return {"messages": [sys_msg] + state["messages"] + [example_msg]}
+
     def retriever(state: MessagesState):
-        """Retriever node"""
-        similar_question = vector_store.similarity_search(state["messages"][0].content)
-        example_msg = HumanMessage(
-            content=f"Here I provide a similar question and answer for reference: \n\n{similar_question[0].page_content}",
-        )
-        return {"messages": [sys_msg] + state["messages"] + [example_msg]}
+    """Retriever node"""
+    query = state["messages"][0].content
+    similar_question = vector_store.similarity_search(query)
+
+    if not similar_question:
+        print("No similar documents found.")
+        return {"messages": [sys_msg] + state["messages"]}
+
+    example_msg = HumanMessage(
+        content=f"Here I provide a similar question and answer for reference: \n\n{similar_question[0].page_content}",
+    )
+    return {"messages": [sys_msg] + state["messages"] + [example_msg]}
+
 
     builder = StateGraph(MessagesState)
     builder.add_node("retriever", retriever)