diff --git a/action.yml b/action.yml
index 442d900..c7428ca 100644
--- a/action.yml
+++ b/action.yml
@@ -51,7 +51,7 @@ inputs:
   source-url:
     description: A URL pointing to a `magic-nix-cache` binary. Overrides all other `source-*` options.
     required: false
-  strict-mode:
+  _internal-strict-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
     required: false