diff --git a/delete-user-data/README.md b/delete-user-data/README.md
index 6f9eeea52f..eede9d4847 100644
--- a/delete-user-data/README.md
+++ b/delete-user-data/README.md
@@ -68,7 +68,7 @@ Here's a series of examples. To delete all the files in your default bucket with
 
 * Auto discovery search depth: If auto discovery is enabled, how deep should auto discovery find collections and documents. For example, setting to `1` would only discover root collections and documents, whereas setting to `9` would search sub-collections 9 levels deep. Defaults to `3`.
 
-* Auto discovery search fields: If auto discovery is enabled, specify what document fields are used to associate the UID with the document. The extension will delete documents where the value for one or more of these fields matches the deleting user’s UID. If left empty, document fields will not be used in auto discovery.
+* Auto discovery search fields: If auto discovery is enabled, specify what document fields are used to associate the UID with the document. The extension will delete documents where the value for one or more of these fields matches the deleting user’s UID. If left empty, the default fields (`id,uid,userId`) are used.
 
 * Search function URL: Specify a URL to call that will return a list of document paths to delete. The extension will send a `POST` request to the specified `URL`, with the `uid` of the deleted user will be provided in the body of the request. The endpoint specified should return an array of firestore paths to delete.
 
diff --git a/delete-user-data/extension.yaml b/delete-user-data/extension.yaml
index 27b44d4635..95e56e7033 100644
--- a/delete-user-data/extension.yaml
+++ b/delete-user-data/extension.yaml
@@ -236,8 +236,7 @@ params:
       If auto discovery is enabled, specify what document fields are used to
       associate the UID with the document. The extension will delete documents
       where the value for one or more of these fields matches the deleting
-      user’s UID. If left empty, document fields will not be used in auto
-      discovery.
+      user’s UID. If left empty, the default fields (`id,uid,userId`) are used.
     type: string
     default: "id,uid,userId"
     required: false