diff --git a/zulip/zulip/examples/edit-message b/zulip/zulip/examples/edit-message
index 85b8ffa..00003f3 100755
--- a/zulip/zulip/examples/edit-message
+++ b/zulip/zulip/examples/edit-message
@@ -36,7 +36,7 @@ Specify your Zulip API credentials and server in a ~/.zuliprc file or using the
 import zulip
 
 parser = zulip.add_default_arguments(argparse.ArgumentParser(usage=usage))
-parser.add_argument('--message-id', default="")
+parser.add_argument('--message-id', type=int)
 parser.add_argument('--subject', default="")
 parser.add_argument('--content', default="")
 options = parser.parse_args()