diff --git a/utils/deactivate_device.py b/utils/deactivate_device.py
index a98ae24..7ff3a94 100755
--- a/utils/deactivate_device.py
+++ b/utils/deactivate_device.py
@@ -1,67 +1,67 @@
 #!/usr/bin/env python3
 
 from phabricator import Phabricator
 import sys
 
 phab = Phabricator(host='https://c4science.ch/api/')
 phab.update_interfaces()
 
 # Disable write on device
 def deactivate_write(action, binding):
     if action == 'off':
         transactions = [
             {'type': 'property.set', 'value': {'writable': False}},
             {'type': 'disabled', 'value': True},
         ]
     else:
         transactions = [
             {'type': 'property.set', 'value': {'writable': True}},
             {'type': 'disabled', 'value': False},
         ]
     print(phab.almanac.binding.edit(
         objectIdentifier = binding,
         transactions = transactions,
     ))
 
 # Get bindinds list
 def get_bindings(devices):
     device = phab.almanac.device.search(
         constraints = {
             'names': devices,
         }
     )
     if len(device.data) == 0:
         print('No device found')
         sys.exit(1)
     devices_phid = [a['phid'] for a in device.data]
 
     service = phab.almanac.service.search(
         constraints = {
             'names': ['repo-cluster', 'repo-single'],
         }
     )
     services_phid = [a['phid'] for a in service.data]
 
     bindings = phab.almanac.binding.search(
         constraints = {
             'servicePHIDs': services_phid,
             'devicePHIDs': devices_phid,
         },
     )
     if len(bindings.data) == 0:
         print('No binding found')
         sys.exit(1)
     return [a['phid'] for a in bindings.data]
 
 # MAIN
 
-action = sys.argv[1]
-devices = sys.argv[2:]
-
-if len(devices) == 0:
+if len(sys.argv) < 2:
     print('USAGE: {cmd} [on|off] [device]...\nexample: {cmd} off c4science-phd00 c4science-phd01'.format(cmd=sys.argv[0]))
     sys.exit(1)
 
+action = sys.argv[1]
+devices = sys.argv[2:]
+
 bindings = get_bindings(devices)
 for binding in bindings:
     deactivate_write(action, binding)