diff --git a/Classes/Fusion/Helper/NodeHelper.php b/Classes/Fusion/Helper/NodeHelper.php
index 9ac7c01..ce92519 100644
--- a/Classes/Fusion/Helper/NodeHelper.php
+++ b/Classes/Fusion/Helper/NodeHelper.php
@@ -4,10 +4,22 @@
 use Neos\ContentRepository\Domain\Model\NodeInterface;
 use Neos\Eel\ProtectedContextAwareInterface;
 
+/**
+ * Custom Eel Helper for node related functions
+ */
 class NodeHelper implements ProtectedContextAwareInterface
 {
 
-    public function mergeProperties(array $properties, NodeInterface $node)
+    /**
+     * Merge properties of the specified $node to the given $properties (with precedence to node properties)
+     *
+     * Note: This is required since NodeInterface::getProperties() does no longer return an array but an instance of PropertyCollectionInterface
+     *
+     * @param array $properties
+     * @param NodeInterface $node
+     * @return array
+     */
+    public function mergeProperties(array $properties, NodeInterface $node): array
     {
         $nodeProperties = $node->getProperties();
         if ($nodeProperties instanceof \Traversable) {