Update app.py

app.py

@@ -271,6 +271,16 @@ def main():
     with col1:
         st.markdown(
             """
+            # Introduction
+            
+            This app builds a [retrieval-augmented generation](https://en.wikipedia.org/wiki/Retrieval-augmented_generation) model that let's you ask "talk" to your document, ask questions, summarize, and extract data.
+            :clap: The workflow relies on:
+            * [OpenAI](https://platform.openai.com/apps)
+            * [LlamaParse](https://cloud.llamaindex.ai/)
+            * [LlamaIndex](https://cloud.llamaindex.ai/)
+            
+            :warning: This tool is provided "as-is" without warranty.
+        
             # Instructions
 
             1. Obtain an [API Key](https://cloud.llamaindex.ai/api-key) from LlamaParse to parse your document. 
@@ -291,7 +301,7 @@ def main():
 
         run = st.button("Answer", type="primary")
 
-        if parsed_document is not None and run and submit_button:
+        if parsed_document is not None and run:
             index = VectorStoreIndex.from_documents(parsed_document)
             query_engine = index.as_query_engine(
                 similarity_top_k=similarity_top_k,