diff --git a/core/blockly.js b/core/blockly.js
index 6091c139d..17e24966f 100644
--- a/core/blockly.js
+++ b/core/blockly.js
@@ -83,6 +83,11 @@ Blockly.highlightedConnection_ = null;
  */
 Blockly.localConnection_ = null;
 
+/**
+ * All of the connections on blocks that are currently being dragged.
+ * @type {!Array.<!Blockly.Connection>}
+ * @private
+ */
 Blockly.draggingConnections_ = [];
 
 /**