diff --git a/doc/authenticator.md b/doc/authenticator.md
index d1c51b2..2434767 100644
--- a/doc/authenticator.md
+++ b/doc/authenticator.md
@@ -3,7 +3,7 @@
 GitBucket provides many [authenticators](https://github.com/gitbucket/gitbucket/blob/master/src/main/scala/gitbucket/core/util/Authenticator.scala) to access controlling in the controller.
 
 For example, in the case of `RepositoryViwerController`,
-it references three authenticators, `ReadableUsersAuthenticator`, `ReferrerAuthenticator` and `CollaboratorsAuthenticator`:
+it references three authenticators: `ReadableUsersAuthenticator`, `ReferrerAuthenticator` and `CollaboratorsAuthenticator`.
 
 ```scala
 class RepositoryViewerController extends RepositoryViewerControllerBase
@@ -19,6 +19,8 @@
   ...
 ```
 
+Authenticators provides a method to add guard to actions in the controller:
+
 - `ReadableUsersAuthenticator` provides `readableUsersOnly` method
 - `ReferrerAuthenticator` provides `referrersOnly` method
 - `CollaboratorsAuthenticator` provides `collaboratorsOnly` method