diff --git a/yesod-auth/Yesod/Auth.hs b/yesod-auth/Yesod/Auth.hs
index 83ec6492..e398a84b 100644
--- a/yesod-auth/Yesod/Auth.hs
+++ b/yesod-auth/Yesod/Auth.hs
@@ -164,7 +164,11 @@ mkYesodSub "Auth"
 /page/#Text/STRINGS PluginR
 |]
 
-setCreds :: YesodAuth master => Bool -> Creds master -> GHandler sub master ()
+-- | Sets user credentials for the session after checking them with authentication backends.
+setCreds :: YesodAuth master
+         => Bool         -- ^ if HTTP redirects should be done
+         -> Creds master -- ^ new credentials
+         -> GHandler sub master ()
 setCreds doRedirects creds = do
     y    <- getYesod
     maid <- getAuthId creds
@@ -185,7 +189,10 @@ $newline never
               onLogin
               redirectUltDest $ loginDest y
 
-clearCreds :: YesodAuth master => Bool -> GHandler sub master ()
+-- | Clears current user credentials for the session.
+clearCreds :: YesodAuth master
+           => Bool -- ^ if HTTP redirect to 'logoutDest' should be done
+           -> GHandler sub master ()
 clearCreds doRedirects = do
     y <- getYesod
     deleteSession credsKey