diff --git a/templates/BaseRenderer.php b/templates/BaseRenderer.php
index <HASH>..<HASH> 100644
--- a/templates/BaseRenderer.php
+++ b/templates/BaseRenderer.php
@@ -34,7 +34,7 @@ abstract class BaseRenderer extends Component
 	/**
 	 * @var array files for guide pages
 	 */
-	public $markDownFiles;
+	public $markDownFiles = [];
 
 	/**
 	 * Renders a given [[Context]].
fixed issue with apidoc without guide