diff --git a/imgrate.py b/imgrate.py
index 8a331f7..1808804 100755
--- a/imgrate.py
+++ b/imgrate.py
@@ -53,7 +53,8 @@ if __name__ == '__main__':
     from sys import exit
 
     def parse_arguments():
-        ap = ArgumentParser()
+        ap = ArgumentParser(description='Find the best quality one among similar images.'
+                                        'Note: image dimensions should match!')
         ap.add_argument('images', type=str, nargs='+', help='')
         ap.add_argument('-d', '--delete', action='store_true', help='Delete all but the best quality image.')
         ap.add_argument('-q', '--quiet', action='store_true', help='Print quality measurements only.')