diff --git a/src/applications/almanac/conduit/AlmanacQueryServicesConduitAPIMethod.php b/src/applications/almanac/conduit/AlmanacQueryServicesConduitAPIMethod.php
index c25d6ba6e8..4cd019fed3 100644
--- a/src/applications/almanac/conduit/AlmanacQueryServicesConduitAPIMethod.php
+++ b/src/applications/almanac/conduit/AlmanacQueryServicesConduitAPIMethod.php
@@ -16,7 +16,7 @@ final class AlmanacQueryServicesConduitAPIMethod
       'ids' => 'optional list<id>',
       'phids' => 'optional list<phid>',
       'names' => 'optional list<phid>',
-      'devicePHIDs' => 'option list<phid>',
+      'devicePHIDs' => 'optional list<phid>',
       'serviceClasses' => 'optional list<string>',
     ) + self::getPagerParamTypes();
   }