Add a description for the app.

app.py

@@ -154,6 +154,14 @@ def get_similar_images(caption, brightness, num_items):
 # Gradio interface
 with gr.Blocks() as demo:
     gr.Markdown("# Image Retrieval using 4M-21: An Any-to-Any Vision Model")
+
+    gr.Markdown("""
+    This app demonstrates image retrieval using the 4M-21 model, an any-to-any vision model. 
+    Enter a caption description, adjust the brightness, and specify the number of items to retrieve similar images.
+    
+    The retrieval dataset for this demo is available at: https://huggingface.co/datasets/aroraaman/4m-21-demo
+    """)
+
     with gr.Row():
         with gr.Column(scale=1):
             caption = gr.Textbox(