diff --git a/server/src/main/java/org/elasticsearch/index/mapper/NestedObjectMapper.java b/server/src/main/java/org/elasticsearch/index/mapper/NestedObjectMapper.java
index 8cfbc44be952e..65748847406ea 100644
--- a/server/src/main/java/org/elasticsearch/index/mapper/NestedObjectMapper.java
+++ b/server/src/main/java/org/elasticsearch/index/mapper/NestedObjectMapper.java
@@ -164,9 +164,13 @@ public MapperBuilderContext createChildContext(String name, Dynamic dynamic) {
 
     private final Explicit<Boolean> includeInRoot;
     private final Explicit<Boolean> includeInParent;
+    // The query to identify parent documents
     private final Query parentTypeFilter;
+    // The path of the nested field
     private final String nestedTypePath;
+    // The query to identify nested documents at this level
     private final Query nestedTypeFilter;
+    // Function to create a bitset for identifying parent documents
     private final Function<Query, BitSetProducer> bitsetProducer;
 
     NestedObjectMapper(