diff --git a/mmcli.py b/mmcli.py
index aac3e12..bdc5857 100755
--- a/mmcli.py
+++ b/mmcli.py
@@ -322,7 +322,7 @@ Hint: JSON output can be filtered on the command line with jq(1).
 
 	argparser.add_argument(
 		"--server",
-		help="e.g.: mattermost.example.org; example.org/mattermost; envvar: {ENVVAR_SERVER}",
+		help=f"e.g.: mattermost.example.org; example.org/mattermost; envvar: {ENVVAR_SERVER}",
 		default=os.getenv(ENVVAR_SERVER))
 
 	subparsers = argparser.add_subparsers(title="actions", dest="action", required=True)