Update app.py

app.py

@@ -73,12 +73,24 @@ if uploaded_file:
         user_question = st.text_input("💬 Type your question here")
 
         if user_question:
-            with st.spinner("Thinking..."):
-                answer = astra_vector_index.query(user_question, llm=llm).strip()
-                st.markdown(f"### 🧠 Answer:\n{answer}")
-
-                st.markdown("### 🔍 Top Relevant Chunks")
-                docs = vector_store.similarity_search_with_score(user_question, k=4)
-                for i, (doc, score) in enumerate(docs, 1):
-                    st.markdown(f"**Chunk {i}** — Relevance Score: `{score:.4f}`")
-                    st.code(doc.page_content[:500], language="markdown")
+           with st.spinner("🧠 Thinking..."):
+              try:
+                # Optional: show what documents are retrieved before sending to LLM
+                retrieved_docs = vector_store.similarity_search(user_question, k=4)
+                if not retrieved_docs:
+                   st.warning("⚠️ No relevant text chunks found for this question. Try a different question.")
+                else:
+                   st.markdown("### 🔍 Top Relevant Chunks (raw):")
+                   for i, doc in enumerate(retrieved_docs, 1):
+                     st.code(doc.page_content[:300], language="markdown")
+
+                 
+                     answer = astra_vector_index.query(user_question, llm=llm)
+                     if answer.strip():
+                        st.markdown("### 🧠 Answer:")
+                        st.write(answer.strip())
+                     else:
+                        st.warning("⚠️ The model returned an empty response. Try rephrasing the question or check your model/API key.")
+              except Exception as e:
+                     st.error(f"🚨 Error while generating response:\n\n{str(e)}")
+