diff --git a/nixos/modules/virtualisation/nixos-container.pl b/nixos/modules/virtualisation/nixos-container.pl
index 9ae5331786c..a94501ea342 100644
--- a/nixos/modules/virtualisation/nixos-container.pl
+++ b/nixos/modules/virtualisation/nixos-container.pl
@@ -22,6 +22,7 @@ Usage: nixos-container list
        nixos-container start <container-name>
        nixos-container stop <container-name>
        nixos-container status <container-name>
+       nixos-container update <container-name> [--config <string>]
        nixos-container login <container-name>
        nixos-container root-login <container-name>
        nixos-container run <container-name> -- args...