diff --git a/flint-core/src/main/scala/org/opensearch/flint/core/storage/FlintOpenSearchMetadataLog.java b/flint-core/src/main/scala/org/opensearch/flint/core/storage/FlintOpenSearchMetadataLog.java
index 4b86e46a5..bbaa43a3d 100644
--- a/flint-core/src/main/scala/org/opensearch/flint/core/storage/FlintOpenSearchMetadataLog.java
+++ b/flint-core/src/main/scala/org/opensearch/flint/core/storage/FlintOpenSearchMetadataLog.java
@@ -36,6 +36,12 @@
 /**
  * Flint metadata log in OpenSearch store. For now use single doc instead of maintaining history
  * of metadata log.
+ * Expects the following fields from maps in FlintMetadataLogEntry:
+ * - entryVersion:
+ *   - seqNo: Long
+ *   - primaryTerm: Long
+ * - storageContext:
+ *   - dataSourceName: String
  */
 public class FlintOpenSearchMetadataLog implements FlintMetadataLog<FlintMetadataLogEntry> {