diff --git a/Gruntfile.js b/Gruntfile.js
index 2e09a71dd0456..9f34d13b57721 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -1,5 +1,4 @@
 /* jshint node:true */
-/* eslint-env es6 */
 /* globals Set */
 var webpackConfig = require( './webpack.config' );
 var installChanged = require( 'install-changed' );
diff --git a/src/js/_enqueues/admin/application-passwords.js b/src/js/_enqueues/admin/application-passwords.js
index c79cdb8b4037f..2e6f2e82c1eed 100644
--- a/src/js/_enqueues/admin/application-passwords.js
+++ b/src/js/_enqueues/admin/application-passwords.js
@@ -2,6 +2,9 @@
  * @output wp-admin/js/application-passwords.js
  */
 
+/**
+ * @param {JQueryStatic} $ The jQuery object.
+ */
 ( function( $ ) {
 	var $appPassSection = $( '#application-passwords-section' ),
 		$newAppPassForm = $appPassSection.find( '.create-application-password' ),
@@ -188,7 +191,7 @@
 	 *
 	 * @param {string} message The message to display.
 	 * @param {string} type    The notice type. Either 'success' or 'error'.
-	 * @returns {jQuery} The notice element.
+	 * @return {jQuery} The notice element.
 	 */
 	function addNotice( message, type ) {
 		var $notice = $( '<div></div>' )
diff --git a/src/js/_enqueues/admin/comment.js b/src/js/_enqueues/admin/comment.js
index b31f174bab5fe..d2ebafbcf4834 100644
--- a/src/js/_enqueues/admin/comment.js
+++ b/src/js/_enqueues/admin/comment.js
@@ -9,7 +9,7 @@
  *
  * @since 2.5.0
  *
- * @param {jQuery} $ The jQuery object.
+ * @param {JQueryStatic} $ The jQuery object.
  */
 jQuery( function($) {
 
diff --git a/src/js/_enqueues/admin/common.js b/src/js/_enqueues/admin/common.js
index c3d49310e8897..735a9aeeaabef 100644
--- a/src/js/_enqueues/admin/common.js
+++ b/src/js/_enqueues/admin/common.js
@@ -8,9 +8,9 @@
 /**
  *  Adds common WordPress functionality to the window.
  *
- *  @param {jQuery} $        jQuery object.
- *  @param {Object} window   The window object.
- *  @param {mixed} undefined Unused.
+ *  @param {JQueryStatic} $         The jQuery object.
+ *  @param {Object}       window    The window object.
+ *  @param {*}            undefined Unused.
  */
 ( function( $, window, undefined ) {
 	var $document = $( document ),
@@ -58,10 +58,10 @@ function deprecatedProperty( propName, version, replacement ) {
  * @since 5.6.0 Added the `version` parameter.
  *
  * @param {string} name       The name of the object, i.e. commonL10n.
- * @param {object} l10nObject The object to deprecate the properties on.
+ * @param {Object} l10nObject The object to deprecate the properties on.
  * @param {string} version    The version of WordPress that deprecated the property.
  *
- * @return {object} The object with all its properties deprecated.
+ * @return {Object} The object with all its properties deprecated.
  */
 function deprecateL10nObject( name, l10nObject, version ) {
 	var deprecatedObject = {};
@@ -476,8 +476,6 @@ window.columns = {
 	 * Gets the checked column toggles from the screen options.
 	 *
 	 * @since 3.0.0
-	 *
-	 * @return {string} String containing the checked column names.
 	 */
 	useCheckboxesForHidden : function() {
 		this.hidden = function(){
@@ -557,7 +555,7 @@ window.showNotice = {
 	 *
 	 * @since 2.7.0
 	 *
-	 * @param text The text to display in the message.
+	 * @param {string} text The text to display in the message.
 	 */
 	note : function(text) {
 		alert(text);
@@ -1263,6 +1261,7 @@ $( function() {
 		/**
 		 * Triggers the primary submit when then secondary submit is clicked.
 		 *
+		 * @param {SubmitEvent} e The event object.
 		 * @since 5.7.0
 		 *
 		 * @return {void}
@@ -2245,6 +2244,8 @@ $( function( $ ) {
  * plugin icon images in the update plugins table.
  *
  * @since 6.4.0
+ *
+ * @return {Object} Public methods.
  */
 (function() {
 	// Private variables and methods.
diff --git a/src/js/_enqueues/admin/custom-background.js b/src/js/_enqueues/admin/custom-background.js
index f83db00af03b4..d8ef84e618bc1 100644
--- a/src/js/_enqueues/admin/custom-background.js
+++ b/src/js/_enqueues/admin/custom-background.js
@@ -10,6 +10,8 @@
  * @since 3.0.0
  *
  * @requires jQuery
+ *
+ * @param {JQueryStatic} $ The jQuery object.
  */
 (function($) {
 	$( function() {
diff --git a/src/js/_enqueues/admin/custom-header.js b/src/js/_enqueues/admin/custom-header.js
index 367756ef8758b..40f9be4f35962 100644
--- a/src/js/_enqueues/admin/custom-header.js
+++ b/src/js/_enqueues/admin/custom-header.js
@@ -11,6 +11,8 @@
  *
  * @deprecated 4.1.0 The page this is used on is never linked to from the UI.
  *             Setting a custom header is completely handled by the Customizer.
+ *
+ * @param {JQueryStatic} $ The jQuery object.
  */
 (function($) {
 	var frame;
diff --git a/src/js/_enqueues/admin/edit-comments.js b/src/js/_enqueues/admin/edit-comments.js
index 78ee78de759ff..4320c8e00f0ea 100644
--- a/src/js/_enqueues/admin/edit-comments.js
+++ b/src/js/_enqueues/admin/edit-comments.js
@@ -1,14 +1,14 @@
+/* global adminCommentsSettings, thousandsSeparator, list_args, QTags, ajaxurl, wpAjax */
+/* global commentReply, theExtraList, theList, setCommentsList */
+
 /**
  * Handles updating and editing comments.
- *
- * @file This file contains functionality for the admin comments page.
- * @since 2.1.0
  * @output wp-admin/js/edit-comments.js
  */
 
-/* global adminCommentsSettings, thousandsSeparator, list_args, QTags, ajaxurl, wpAjax */
-/* global commentReply, theExtraList, theList, setCommentsList */
-
+/**
+ * @param {JQueryStatic} $ The jQuery object.
+ */
 (function($) {
 var getCount, updateCount, updateCountText, updatePending, updateApproved,
 	updateHtmlTitle, updateDashboardText, updateInModerationText, adminTitle = document.title,
diff --git a/src/js/_enqueues/admin/inline-edit-post.js b/src/js/_enqueues/admin/inline-edit-post.js
index 6e6e3bef606ed..7f469137fc1bd 100644
--- a/src/js/_enqueues/admin/inline-edit-post.js
+++ b/src/js/_enqueues/admin/inline-edit-post.js
@@ -21,6 +21,9 @@ window.wp = window.wp || {};
  * @property {string} type The type of inline editor.
  * @property {string} what The prefix before the post ID.
  *
+ * @param {JQueryStatic} $ The jQuery object.
+ * @param {wp}           wp The WordPress global object.
+ *
  */
 ( function( $, wp ) {
 
@@ -188,6 +191,8 @@ window.wp = window.wp || {};
 	 * @since 2.7.0
 	 *
 	 * @memberof inlineEditPost
+	 *
+	 * @return {void|false} Returns false if no checkboxes are checked, otherwise does not return anything.
 	 */
 	setBulk : function(){
 		var te = '', type = this.type, c = true;
diff --git a/src/js/_enqueues/admin/inline-edit-tax.js b/src/js/_enqueues/admin/inline-edit-tax.js
index 86e3498cd1eac..620533455f6be 100644
--- a/src/js/_enqueues/admin/inline-edit-tax.js
+++ b/src/js/_enqueues/admin/inline-edit-tax.js
@@ -16,6 +16,9 @@ window.wp = window.wp || {};
  * @property {string} type The type of inline edit we are currently on.
  * @property {string} what The type property with a hash prefixed and a dash
  *                         suffixed.
+ *
+ * @param {JQueryStatic} $  The jQuery object.
+ * @param {Object}       wp The WordPress object.
  */
 ( function( $, wp ) {
 
diff --git a/src/js/_enqueues/admin/post.js b/src/js/_enqueues/admin/post.js
index 445e79d8a6f05..2eac2f828397a 100644
--- a/src/js/_enqueues/admin/post.js
+++ b/src/js/_enqueues/admin/post.js
@@ -14,6 +14,9 @@ window.makeSlugeditClickable = window.editPermalink = function(){};
 // Make sure the wp object exists.
 window.wp = window.wp || {};
 
+/**
+ * @param {JQueryStatic} $ The jQuery object.
+ */
 ( function( $ ) {
 	var titleHasFocus = false,
 		__ = wp.i18n.__;
@@ -254,6 +257,8 @@ window.wp = window.wp || {};
 
 /**
  * Heartbeat refresh nonces.
+ *
+ * @param {JQueryStatic} $ The jQuery object.
  */
 (function($) {
 	var check, timeout;
@@ -300,6 +305,8 @@ window.wp = window.wp || {};
 
 /**
  * All post and postbox controls and functionality.
+ *
+ * @param {JQueryStatic} $ The jQuery object.
  */
 jQuery( function($) {
 	var stamp, visibility, $submitButtons, updateVisibility, updateText,
@@ -620,11 +627,11 @@ jQuery( function($) {
 		});
 
 		/**
-		 * Before adding a new taxonomy, disable submit button.
+		 * Disables the submit button before adding a new taxonomy.
 		 *
 		 * @param {Object} s Taxonomy object which will be added.
 		 *
-		 * @return {Object}
+		 * @return {Object} Taxonomy object with additional data to be sent to the server.
 		 */
 		catAddBefore = function( s ) {
 			if ( !$('#new'+taxonomy).val() ) {
@@ -1322,6 +1329,9 @@ jQuery( function($) {
 
 /**
  * TinyMCE word count display
+ *
+ * @param {JQueryStatic}         $       The jQuery object.
+ * @param {wp.utils.WordCounter} counter The WordCounter object.
  */
 ( function( $, counter ) {
 	$( function() {
diff --git a/src/js/_enqueues/admin/site-health.js b/src/js/_enqueues/admin/site-health.js
index 57d5c9cbcf289..98aaedc427c0e 100644
--- a/src/js/_enqueues/admin/site-health.js
+++ b/src/js/_enqueues/admin/site-health.js
@@ -85,9 +85,9 @@ jQuery( function( $ ) {
 	 *
 	 * @since 5.6.0
 	 *
-	 * @param {Object} issue
+	 * @param {Object} issue The issue data to validate.
 	 *
-	 * @return {boolean}
+	 * @return {boolean} True if the issue data is valid, false otherwise.
 	 */
 	function validateIssueData( issue ) {
 		// Expected minimum format of a valid SiteHealth test response.
@@ -137,6 +137,7 @@ jQuery( function( $ ) {
 	 * @since 5.2.0
 	 *
 	 * @param {Object} issue The issue data.
+	 * @return {void|boolean} True if the issue was appended, false otherwise.
 	 */
 	function appendIssue( issue ) {
 		var template = wp.template( 'health-check-issue' ),
@@ -346,6 +347,8 @@ jQuery( function( $ ) {
 	/**
 	 * Add the details of a failed asynchronous test to the list of test results.
 	 *
+	 * @param {string} url
+	 * @param {string} description
 	 * @since 5.6.0
 	 */
 	function addFailedSiteHealthCheckNotice( url, description ) {
diff --git a/src/js/_enqueues/admin/site-icon.js b/src/js/_enqueues/admin/site-icon.js
index a4f94797a5a48..59a098dc08aac 100644
--- a/src/js/_enqueues/admin/site-icon.js
+++ b/src/js/_enqueues/admin/site-icon.js
@@ -141,7 +141,7 @@
 	 *
 	 * @since 6.5.0
 	 *
-	 * @param {array} attributes The attributes for the attachment.
+	 * @param {Object} attributes The attributes for the attachment.
 	 */
 	function switchToUpdate( attributes ) {
 		var i18nAppAlternativeString, i18nBrowserAlternativeString;
diff --git a/src/js/_enqueues/admin/tags-suggest.js b/src/js/_enqueues/admin/tags-suggest.js
index d439f06ef0de8..08bea1464bbbe 100644
--- a/src/js/_enqueues/admin/tags-suggest.js
+++ b/src/js/_enqueues/admin/tags-suggest.js
@@ -2,6 +2,8 @@
  * Default settings for jQuery UI Autocomplete for use with non-hierarchical taxonomies.
  *
  * @output wp-admin/js/tags-suggest.js
+ *
+ * @param {JQueryStatic} $ The jQuery object.
  */
 ( function( $ ) {
 	var tempID = 0;
diff --git a/src/js/_enqueues/admin/tags.js b/src/js/_enqueues/admin/tags.js
index 88e38b6926309..8d449ca986863 100644
--- a/src/js/_enqueues/admin/tags.js
+++ b/src/js/_enqueues/admin/tags.js
@@ -9,6 +9,9 @@
 
  /* global ajaxurl, wpAjax, showNotice, validateForm */
 
+ /**
+  * @param {JQueryStatic} $ The jQuery object.
+  */
 jQuery( function($) {
 
 	var addingTerm = false;
diff --git a/src/js/_enqueues/admin/user-profile.js b/src/js/_enqueues/admin/user-profile.js
index 6a6be6745e357..c2bd1a78dc179 100644
--- a/src/js/_enqueues/admin/user-profile.js
+++ b/src/js/_enqueues/admin/user-profile.js
@@ -1,8 +1,12 @@
+/* global ajaxurl, pwsL10n, userProfileL10n, ClipboardJS */
+
 /**
  * @output wp-admin/js/user-profile.js
  */
 
-/* global ajaxurl, pwsL10n, userProfileL10n, ClipboardJS */
+/**
+ * @param {JQueryStatic} $ The jQuery object.
+ */
 (function($) {
 	var updateLock = false,
 		isSubmitting = false,
@@ -160,7 +164,7 @@
 	 *
 	 * @param {jQuery Object} $this   The button element: the message will be inserted
 	 *                                above this button
-	 * @param {bool}          success Whether the message is a success message.
+	 * @param {boolean}       success Whether the message is a success message.
 	 * @param {string}        message The message to insert.
 	 */
 	function addInlineNotice( $this, success, message ) {
@@ -400,7 +404,7 @@
 	 * On macOS Safari and Firefox, the native warning is preferred,
 	 * so this function returns false to suppress custom warnings.
 	 *
-	 * @param {KeyboardEvent} e The keydown event object.
+	 * @param {KeyboardEvent} event The keydown event object.
 	 *
 	 * @return {boolean} True if Caps Lock is on, false otherwise.
 	 */
diff --git a/src/js/_enqueues/admin/widgets.js b/src/js/_enqueues/admin/widgets.js
index e8fc42507d382..cbd8f8dd4a222 100644
--- a/src/js/_enqueues/admin/widgets.js
+++ b/src/js/_enqueues/admin/widgets.js
@@ -11,14 +11,14 @@ window.wpWidgets = {
 	/**
 	 * A closed Sidebar that gets a Widget dragged over it.
 	 *
-	 * @var {element|null}
+	 * @member {jQuery|null}
 	 */
 	hoveredSidebar: null,
 
 	/**
 	 * Lookup of which widgets have had change events triggered.
 	 *
-	 * @var {object}
+	 * @member {Object}
 	 */
 	dirtyWidgets: {},
 
@@ -751,7 +751,7 @@ $( function(){ wpWidgets.init(); } );
  * @since 4.9.0
  * @deprecated 5.5.0
  *
- * @type {object}
+ * @type {Object}
 */
 wpWidgets.l10n = wpWidgets.l10n || {
 	save: '',
diff --git a/src/js/_enqueues/lib/accordion.js b/src/js/_enqueues/lib/accordion.js
index 9b52b179b22a6..12daff74a0daf 100644
--- a/src/js/_enqueues/lib/accordion.js
+++ b/src/js/_enqueues/lib/accordion.js
@@ -29,6 +29,9 @@
  * @output wp-admin/js/accordion.js
  */
 
+/**
+ * @param {JQueryStatic} $ The jQuery object.
+ */
 ( function( $ ){
 
 	$( function () {
diff --git a/src/js/_enqueues/lib/admin-bar.js b/src/js/_enqueues/lib/admin-bar.js
index 619694db37f5c..3d6f4e3c8b94d 100644
--- a/src/js/_enqueues/lib/admin-bar.js
+++ b/src/js/_enqueues/lib/admin-bar.js
@@ -206,7 +206,7 @@
 	 * @since 5.3.1 Use querySelector to clean up the function.
 	 *
 	 * @param {Event} event The click event.
-	 * @return {boolean} Returns false to prevent default click behavior.
+	 * @return {boolean|void} False to prevent default action.
 	 */
 	function clickShortlink( event ) {
 		var wrapper = event.target.parentNode,
@@ -397,6 +397,8 @@
 	 *
 	 * @param {HTMLElement} el Element to get parent.
 	 * @param {string} selector CSS selector to match.
+	 *
+	 * @return {HTMLElement|null} The closest matching element or null if not found.
 	 */
 	function getClosest( el, selector ) {
 		if ( ! window.Element.prototype.matches ) {
diff --git a/src/js/_enqueues/lib/auth-check.js b/src/js/_enqueues/lib/auth-check.js
index ff64573639a25..f01b14b35e386 100644
--- a/src/js/_enqueues/lib/auth-check.js
+++ b/src/js/_enqueues/lib/auth-check.js
@@ -4,6 +4,9 @@
  * @output wp-includes/js/wp-auth-check.js
  */
 
+/**
+ * @param {JQueryStatic} $ The jQuery object.
+ */
 ( function( $ ) {
 	var wrap,
 		tempHidden,
diff --git a/src/js/_enqueues/lib/color-picker.js b/src/js/_enqueues/lib/color-picker.js
index 600e0235b3bdb..51d68cbff4473 100644
--- a/src/js/_enqueues/lib/color-picker.js
+++ b/src/js/_enqueues/lib/color-picker.js
@@ -1,7 +1,13 @@
 /**
  * @output wp-admin/js/color-picker.js
+ *
+ * @since 3.5.0
  */
 
+/**
+ * @param {JQueryStatic} $     The jQuery object.
+ * @param {undefined}    undef The undefined value.
+ */
 ( function( $, undef ) {
 
 	var ColorPicker,
@@ -320,11 +326,11 @@
 		/**
 		 * Returns the iris object if no new color is provided. If a new color is provided, it sets the new color.
 		 *
-		 * @param newColor {string|*} The new color to use. Can be undefined.
+		 * @param {string|*} newColor The new color to use. Can be undefined.
 		 *
 		 * @since 3.5.0
 		 *
-		 * @return {string} The element's color.
+		 * @return {string|void} The element's color.
 		 */
 		color: function( newColor ) {
 			if ( newColor === undef ) {
@@ -332,15 +338,16 @@
 			}
 			this.element.iris( 'option', 'color', newColor );
 		},
+
 		/**
 		 * Returns the iris object if no new default color is provided.
 		 * If a new default color is provided, it sets the new default color.
 		 *
-		 * @param newDefaultColor {string|*} The new default color to use. Can be undefined.
+		 * @param {string|*} newDefaultColor The new default color to use. Can be undefined.
 		 *
 		 * @since 3.5.0
 		 *
-		 * @return {boolean|string} The element's color.
+		 * @return {string|void} The element's default color.
 		 */
 		defaultColor: function( newDefaultColor ) {
 			if ( newDefaultColor === undef ) {
diff --git a/src/js/_enqueues/lib/comment-reply.js b/src/js/_enqueues/lib/comment-reply.js
index fabd579f5afc2..6ebc181551f79 100644
--- a/src/js/_enqueues/lib/comment-reply.js
+++ b/src/js/_enqueues/lib/comment-reply.js
@@ -127,7 +127,7 @@ window.addComment = ( function( window ) {
 	 *
 	 * @param {HTMLElement} context The parent DOM element to search for links.
 	 *
-	 * @return {HTMLCollection|NodeList|Array}
+	 * @return {HTMLCollection|NodeList} The collection of links.
 	 */
 	function replyLinks( context ) {
 		var selectorClass = config.commentReplyClass;
@@ -270,10 +270,10 @@ window.addComment = ( function( window ) {
 	 *
 	 * @since 5.1.0
 	 *
-	 * @param {HTMLElement} Element DOM element with the attribute.
-	 * @param {string}      Attribute the attribute to get.
+	 * @param {HTMLElement} element   DOM element with the attribute.
+	 * @param {string}      attribute The attribute to get.
 	 *
-	 * @return {string}
+	 * @return {string} The value of the attribute.
 	 */
 	function getDataAttribute( element, attribute ) {
 		if ( supportsDataset ) {
@@ -291,7 +291,9 @@ window.addComment = ( function( window ) {
 	 *
 	 * @since 5.1.0
 	 *
-	 * @param {HTMLElement} The requested element.
+	 * @param {string} elementId The requested element.
+	 *
+	 * @return {HTMLElement} The element with the given ID.
 	 */
 	function getElementById( elementId ) {
 		return document.getElementById( elementId );
@@ -309,6 +311,8 @@ window.addComment = ( function( window ) {
 	 * @param {string} respondId  HTML ID of 'respond' element.
 	 * @param {string} postId     Database ID of the post.
 	 * @param {string} replyTo    Form heading content.
+	 *
+	 * @return {void|boolean} Returns false for backward compatibility with third party commenting systems hooking into this function.
 	 */
 	function moveForm( addBelowId, commentId, respondId, postId, replyTo ) {
 		// Get elements based on their IDs.
diff --git a/src/js/_enqueues/lib/cookies.js b/src/js/_enqueues/lib/cookies.js
index 66d920affaa85..30a29d496a02e 100644
--- a/src/js/_enqueues/lib/cookies.js
+++ b/src/js/_enqueues/lib/cookies.js
@@ -40,6 +40,9 @@ window.wpCookies = {
 	/**
 	 * Get a multi-values cookie.
 	 * Returns a JS object with the name: 'value' pairs.
+	 *
+	 * @param {string} name The name of the cookie.
+	 * @return {Object} The cookie values as a JS object.
 	 */
 	getHash: function( name ) {
 		var cookie = this.get( name ), values;
@@ -59,6 +62,13 @@ window.wpCookies = {
 	 * Set a multi-values cookie.
 	 *
 	 * 'values_obj' is the JS object that is stored. It is encoded as URI in wpCookies.set().
+	 *
+	 * @param {string}      name         The name of the cookie.
+	 * @param {Object}      values_obj   The values to store in the cookie.
+	 * @param {number|Date} [expires]    Optional. Expiration time in seconds or a Date object.
+	 * @param {string}      [path]       Optional. The path on the server in which the cookie will be available on.
+	 * @param {string}      [domain]     Optional. The domain that the cookie is available to.
+	 * @param {boolean}     [secure]     Optional. Whether the cookie should only be transmitted over a secure HTTPS connection.
 	 */
 	setHash: function( name, values_obj, expires, path, domain, secure ) {
 		var str = '';
@@ -72,6 +82,8 @@ window.wpCookies = {
 
 	/**
 	 * Get a cookie.
+	 * @param {string} name The name of the cookie.
+	 * @return {void|string} The cookie value.
 	 */
 	get: function( name ) {
 		var e, b,
@@ -107,7 +119,14 @@ window.wpCookies = {
 	 * Set a cookie.
 	 *
 	 * The 'expires' arg can be either a JS Date() object set to the expiration date (back-compat)
-	 * or the number of seconds until expiration
+	 * or the number of seconds until expiration.
+	 *
+	 * @param {string}      name      The name of the cookie.
+	 * @param {string}      value     The value of the cookie.
+	 * @param {number|Date} [expires] Optional. Expiration time in seconds or a Date object.
+	 * @param {string}      [path]    Optional. The path on the server in which the cookie will be available on.
+	 * @param {string}      [domain]  Optional. The domain that the cookie is available to.
+	 * @param {boolean}     [secure]  Optional. Whether the cookie should only be transmitted over a secure HTTPS connection.
 	 */
 	set: function( name, value, expires, path, domain, secure ) {
 		var d = new Date();
@@ -132,6 +151,11 @@ window.wpCookies = {
 	 * Remove a cookie.
 	 *
 	 * This is done by setting it to an empty value and setting the expiration time in the past.
+	 *
+	 * @param {string}  name     The name of the cookie.
+	 * @param {string}  [path]   Optional. The path on the server in which the cookie will be available on.
+	 * @param {string}  [domain] Optional. The domain that the cookie is available to.
+	 * @param {boolean} [secure] Optional. Whether the cookie should only be transmitted over a secure HTTPS connection.
 	 */
 	remove: function( name, path, domain, secure ) {
 		this.set( name, '', -1000, path, domain, secure );
diff --git a/src/js/_enqueues/lib/emoji-loader.js b/src/js/_enqueues/lib/emoji-loader.js
index 4882107670174..86963a2a3af24 100644
--- a/src/js/_enqueues/lib/emoji-loader.js
+++ b/src/js/_enqueues/lib/emoji-loader.js
@@ -2,14 +2,12 @@
  * @output wp-includes/js/wp-emoji-loader.js
  */
 
-/* eslint-env es6 */
-
 // Note: This is loaded as a script module, so there is no need for an IIFE to prevent pollution of the global scope.
 
 /**
  * Emoji Settings as exported in PHP via _print_emoji_detection_script().
  * @typedef WPEmojiSettings
- * @type {object}
+ * @type {Object}
  * @property {?object} source
  * @property {?string} source.concatemoji
  * @property {?string} source.twemoji
@@ -29,7 +27,7 @@ window._wpemojiSettings = settings;
 /**
  * Support tests.
  * @typedef SupportTests
- * @type {object}
+ * @type {Object}
  * @property {?boolean} flag
  * @property {?boolean} emoji
  */
@@ -44,7 +42,7 @@ const tests = [ 'flag', 'emoji' ];
  *
  * @private
  *
- * @returns {boolean}
+ * @return {boolean} True if the browser supports offloading to a Worker.
  */
 function supportsWorkerOffloading() {
 	return (
@@ -58,7 +56,7 @@ function supportsWorkerOffloading() {
 
 /**
  * @typedef SessionSupportTests
- * @type {object}
+ * @type {Object}
  * @property {number} timestamp
  * @property {SupportTests} supportTests
  */
@@ -70,7 +68,7 @@ function supportsWorkerOffloading() {
  *
  * @private
  *
- * @returns {?SupportTests} Support tests, or null if not set or older than 1 week.
+ * @return {?SupportTests} Support tests, or null if not set or older than 1 week.
  */
 function getSessionSupportTests() {
 	try {
diff --git a/src/js/_enqueues/lib/image-edit.js b/src/js/_enqueues/lib/image-edit.js
index d1603051d7078..0431551aeb615 100644
--- a/src/js/_enqueues/lib/image-edit.js
+++ b/src/js/_enqueues/lib/image-edit.js
@@ -1,12 +1,13 @@
+ /* global ajaxurl, confirm */
+
 /**
  * The functions necessary for editing images.
  *
  * @since 2.9.0
  * @output wp-admin/js/image-edit.js
+ *
+ * @param {JQueryStatic} $ The jQuery object.
  */
-
- /* global ajaxurl, confirm */
-
 (function($) {
 	var __ = wp.i18n.__;
 
@@ -23,6 +24,10 @@
 
 	/**
 	 * Enable crop tool.
+	 *
+	 * @param {number}      postid     The post ID.
+	 * @param {string}      nonce      The nonce to verify the request.
+	 * @param {HTMLElement} cropButton The crop button element.
 	 */
 	toggleCropTool: function( postid, nonce, cropButton ) {
 		var img = $( '#image-preview-' + postid ),
@@ -64,6 +69,10 @@
 
 	/**
 	 * Handle crop tool clicks.
+	 *
+	 * @param {number}      postid     The post ID.
+	 * @param {string}      nonce      The nonce to verify the request.
+	 * @param {HTMLElement} cropButton The crop button element.
 	 */
 	handleCropToolClick: function( postid, nonce, cropButton ) {
 
@@ -269,8 +278,6 @@
 	 *
 	 * @memberof imageEdit
 	 *
-	 * @param {HTMLElement} el The activated control element.
-	 *
 	 * @return {boolean} Always returns false.
 	 */
 	monitorPopup : function() {
@@ -567,7 +574,7 @@
 	 *
 	 * @param {number}   postid   The post ID.
 	 * @param {string}   nonce    The nonce to verify the request.
-	 * @param {function} callback Function to execute when the image is loaded.
+	 * @param {Function} callback Function to execute when the image is loaded.
 	 *
 	 * @return {void}
 	 */
@@ -1002,7 +1009,7 @@
 			 * @param {Object} img jQuery object representing the image.
 			 * @param {Object} c   The selection.
 			 *
-			 * @return {Object}
+			 * @return {void}
 			 */
 			onSelectEnd: function(img, c) {
 				imageEdit.setCropSelection(postid, c);
@@ -1047,7 +1054,7 @@
 	 * @param {number} postid The post ID.
 	 * @param {Object} c      The selection.
 	 *
-	 * @return {boolean}
+	 * @return {boolean|void} Returns false if the selection is invalid.
 	 */
 	setCropSelection : function(postid, c) {
 		var sel,
@@ -1197,7 +1204,7 @@
 	 * @param {string} nonce  The nonce.
 	 * @param {Object} t      The target element.
 	 *
-	 * @return {boolean}
+	 * @return {boolean|void} Returns false if the rotate button is disabled.
 	 */
 	rotate : function(angle, postid, nonce, t) {
 		if ( $(t).hasClass('disabled') ) {
@@ -1224,7 +1231,7 @@
 	 * @param {string} nonce  The nonce.
 	 * @param {Object} t      The target element.
 	 *
-	 * @return {boolean}
+	 * @return {boolean|void} Returns false if the flip button is disabled.
 	 */
 	flip : function (axis, postid, nonce, t) {
 		if ( $(t).hasClass('disabled') ) {
diff --git a/src/js/_enqueues/lib/list-revisions.js b/src/js/_enqueues/lib/list-revisions.js
index db0485ef97a08..80ce2e909f287 100644
--- a/src/js/_enqueues/lib/list-revisions.js
+++ b/src/js/_enqueues/lib/list-revisions.js
@@ -1,4 +1,5 @@
 /**
+ * @param {Window} w The global window object.
  * @output wp-includes/js/wp-list-revisions.js
  */