diff --git a/modules/ext.RevisionSlider.RevisionList.js b/modules/ext.RevisionSlider.RevisionList.js
index 4d380d1f..5226ccf1 100644
--- a/modules/ext.RevisionSlider.RevisionList.js
+++ b/modules/ext.RevisionSlider.RevisionList.js
@@ -21,7 +21,7 @@
 		view: null,
 
 		/**
-		 * Inititializes the RevisionList from a list of Revisions
+		 * Initializes the RevisionList from a list of Revisions
 		 *
 		 * @param {Revision[]} revs
 		 */
diff --git a/modules/ext.RevisionSlider.RevisionListView.js b/modules/ext.RevisionSlider.RevisionListView.js
index 7f00e921..57e74211 100644
--- a/modules/ext.RevisionSlider.RevisionListView.js
+++ b/modules/ext.RevisionSlider.RevisionListView.js
@@ -1,7 +1,7 @@
 ( function ( mw, $ ) {
 	/**
 	 * @param {RevisionList} revisionList
-	 * @param {string} dir
+	 * @param {string} [dir]
 	 * @constructor
 	 */
 	var RevisionListView = function ( revisionList, dir ) {
diff --git a/modules/ext.RevisionSlider.Settings.js b/modules/ext.RevisionSlider.Settings.js
index 49f24fea..72ae0510 100644
--- a/modules/ext.RevisionSlider.Settings.js
+++ b/modules/ext.RevisionSlider.Settings.js
@@ -73,7 +73,7 @@
 
 		/**
 		 * @param {string} name
-		 * @param {boolean} defaultValue
+		 * @param {boolean} [defaultValue]
 		 * @return {boolean}
 		 */
 		loadBoolean: function ( name, defaultValue ) {