diff --git a/action.yml b/action.yml
index 4322016..75f39ac 100644
--- a/action.yml
+++ b/action.yml
@@ -129,6 +129,9 @@ inputs:
   nix-installer-url:
     description: (deprecated) A URL pointing to a `nix-installer.sh` script
     required: false
+  ci-mode:
+    description: Whether to fail when any errors are thrown. Used only to test the Action; do not set this in your own workflows.
+    default: false
 
 runs:
   using: "node20"