diff --git a/client/coral-framework/components/Slot.js b/client/coral-framework/components/Slot.js
index 838382978..c0cca143c 100644
--- a/client/coral-framework/components/Slot.js
+++ b/client/coral-framework/components/Slot.js
@@ -51,6 +51,8 @@ class Slot extends React.Component {
 
 Slot.propTypes = {
   fill: React.PropTypes.string.isRequired,
+
+  // props coming from graphql must be passed through this property.
   queryData: React.PropTypes.object,
 };