diff --git a/fold-entity-row.js b/fold-entity-row.js
index da1a55f..0f70948 100644
--- a/fold-entity-row.js
+++ b/fold-entity-row.js
@@ -104,6 +104,8 @@ class FoldEntityRow extends LitElement {
   }
 
   setConfig(config) {
+    if(!window.cardTools) throw new Error(`Can't find card-tools. See https://github.com/thomasloven/lovelace-card-tools`);
+    window.cardTools.checkVersion(0.1);
     this._config = config;
     this._closed = !config.open;