diff --git a/next-release-notes.md b/next-release-notes.md
index f77d5bd6..dec6c01f 100644
--- a/next-release-notes.md
+++ b/next-release-notes.md
@@ -4,6 +4,7 @@
 ### Features
 
 ### Bug Fixes and Improvements
+ - Added some documentation on the data structure required by a StaticDataProvider.
 
 ### Other Changes
--->
\ No newline at end of file
+-->
diff --git a/packages/docs/docs/guides/uncontrolled-environment.mdx b/packages/docs/docs/guides/uncontrolled-environment.mdx
index 582bf292..7bdc0743 100644
--- a/packages/docs/docs/guides/uncontrolled-environment.mdx
+++ b/packages/docs/docs/guides/uncontrolled-environment.mdx
@@ -58,6 +58,8 @@ function App() {
 }
 ```
 
+Note that for each item in the data structure representing the tree (`items` in this case), each object must have a field named `index` that has the same value as the key for that object.  The `children` array can only refer to these values as well.
+
 ## Component Props
 
 The props for the `UncontrolledTreeEnvironment` are as follows: