diff --git a/amoro-ams/src/main/java/org/apache/amoro/server/optimizing/RewriteStageTask.java b/amoro-ams/src/main/java/org/apache/amoro/server/optimizing/RewriteStageTask.java
index 164ebfef3b..df9efa2710 100644
--- a/amoro-ams/src/main/java/org/apache/amoro/server/optimizing/RewriteStageTask.java
+++ b/amoro-ams/src/main/java/org/apache/amoro/server/optimizing/RewriteStageTask.java
@@ -26,6 +26,10 @@
 
 import java.util.Map;
 
+/**
+ * RewriteStageTask is a task which contains the input and output of a rewrite stage task. Other
+ * stage task would include plan, evaluate, commit, etc.
+ */
 public class RewriteStageTask
     extends StagedTaskDescriptor<RewriteFilesInput, RewriteFilesOutput, MetricsSummary> {