diff --git a/server.py b/server.py
index b9e28cb..d878e7c 100755
--- a/server.py
+++ b/server.py
@@ -29,7 +29,7 @@ def parse_args():
     parser.add_argument("-c", "--charge-control", help="enable charge control, default charge_config.json",
                         const="charge_config.json", nargs='?', metavar='charge config file')
     parser.add_argument("-d", "--debug", help="enable debug", const=10, default=20, nargs='?',
-                        metavar='Debug level number', type=int)
+                        metavar='Debug level number or name')
     parser.add_argument("-l", "--listen", help="change server listen address", default="127.0.0.1", metavar="IP")
     parser.add_argument("-p", "--port", help="change server listen port", default="5000")
     parser.add_argument("-r", "--record", help="save vehicle data to db", action='store_true')