diff --git a/maintainers/scripts/update.nix b/maintainers/scripts/update.nix
index 6543a6259828..3aff32caf581 100755
--- a/maintainers/scripts/update.nix
+++ b/maintainers/scripts/update.nix
@@ -1,3 +1,10 @@
+/*
+  To run:
+
+      nix-shell maintainers/scripts/update.nix
+
+  See https://nixos.org/manual/nixpkgs/unstable/#var-passthru-updateScript
+*/
 { package ? null
 , maintainer ? null
 , predicate ? null
@@ -8,8 +15,6 @@
 , commit ? null
 }:
 
-# TODO: add assert statements
-
 let
   pkgs = import ./../../default.nix (
     if include-overlays == false then