diff --git a/events/db_update.go b/events/db_update.go
index a6865b8707..1d802d3e3a 100644
--- a/events/db_update.go
+++ b/events/db_update.go
@@ -22,12 +22,24 @@ type UpdateChannel = immutable.Option[Channel[Update]]
 // EmptyUpdateChannel is an empty UpdateChannel.
 var EmptyUpdateChannel = immutable.None[Channel[Update]]()
 
-// UpdateEvent represents a new DAG node added to the append-only MerkleCRDT Clock graph
-// of a document or sub-field.
+// UpdateEvent represents a new DAG node added to the append-only composite MerkleCRDT Clock graph
+// of a document.
+//
+// It must only contain public elements not protected by ACP.
 type Update struct {
-	DocID      string
-	Cid        cid.Cid
+	// DocID is the unique immutable identifier of the document that was updated.
+	DocID string
+
+	// Cid is the id of the composite commit that formed this update in the DAG.
+	Cid cid.Cid
+
+	// SchemaRoot is the root identifier of the schema that defined the shape of the document that was updated.
 	SchemaRoot string
-	Block      ipld.Node
-	Priority   uint64
+
+	// Block is the contents of this composite commit, it contains the Cids of the field level commits that
+	// also formed this update.
+	Block ipld.Node
+
+	// Priority is used to determine the order in which concurrent updates are applied.
+	Priority uint64
 }