diff --git a/doc/TOOL_API.md b/doc/TOOL_API.md
index 10409b4..559281c 100644
--- a/doc/TOOL_API.md
+++ b/doc/TOOL_API.md
@@ -73,6 +73,7 @@ Check dom element status.
 |Name               |Type   |Desc                 |
 |-------------------|-------|---------------------|
 |overrideEventTarget|boolean|Catch Event Listeners|
+|observeElement     |boolean|Auto Refresh         |
 
 ### set