diff --git a/README.md b/README.md
index d0a35b1..5501b4b 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,10 @@
 This repository contains the code and scripts that we use to prepare Node.js packages used in [virtual-environments](https://github.com/actions/virtual-environments) and accessible through the [setup-node](https://github.com/actions/setup-node) Action.  
 File [versions-manifest.json](./versions-manifest.json) contains the list of available and released versions.  
 
+> Caution: this is prepared for and only permitted for use by actions `virtual-environments` and `setup-node` action.
+
+**Status**: Currently under development and in use for beta and preview actions.  This repo is undergoing rapid changes.
+
 Some versions are pre-installed on [virtual-environments](https://github.com/actions/virtual-environments) images.  
 More versions will (soon!) be available to install on-the-fly through the [`setup-node`](https://github.com/actions/setup-node) action.