diff --git a/feeds.js b/feeds.js
index b92254d..2b31ccd 100644
--- a/feeds.js
+++ b/feeds.js
@@ -1,3 +1,13 @@
+/**
+ * @file
+ * JS for the feeds admin UI.
+ */
+
+/**
+ * Sets URL hash so that the correct settings tab is open on the feed type form.
+ *
+ * @see \Drupal\feeds\FeedTypeForm::ajaxCallback
+ */
 Drupal.AjaxCommands.prototype.feedsHash = function (ajax, response, status) {
 
   "use strict";
diff --git a/feeds.module b/feeds.module
index b4119bb..56aaa2f 100644
--- a/feeds.module
+++ b/feeds.module
@@ -115,11 +115,15 @@ function feeds_file_download($uri) {
 }
 
 /**
- * Implements hook_form_FORM_ID_alter().
+ * Implements hook_form_FORM_ID_alter() for field_ui_field_overview_form().
  *
- * Remove our field from the Field UI overview form.
+ * Removes our field from the Field UI overview form.
+ *
+ * @todo implement the feeds_item field as base field instead? See
+ * https://www.drupal.org/project/feeds/issues/2799225
  */
 function feeds_form_field_ui_field_overview_form_alter(array &$form, FormStateInterface $form_state) {
+  // @codingStandardsIgnoreStart
   // if (in_array('feeds_item', $form['#fields'])) {
 
   //   unset($form['#fields'][array_search('feeds_item', $form['#fields'])]);
@@ -129,6 +133,7 @@ function feeds_form_field_ui_field_overview_form_alter(array &$form, FormStateIn
   //   $key = array_search('feeds_item', $rows_order);
   //   unset($form['fields']['#regions']['content']['rows_order'][$key]);
   // }
+  // @codingStandardsIgnoreEnd
 }
 
 /**
diff --git a/feeds.ui.css b/feeds.ui.css
index cff0e26..c0d99db 100644
--- a/feeds.ui.css
+++ b/feeds.ui.css
@@ -17,9 +17,6 @@ table.feeds-admin-feed-type tr.disabled.odd {
 }
 
 /* Feeds edit form layout. */
-div.feeds-settings {
-}
-
 div.left-bar {
   float: left;
   position: relative;
@@ -38,9 +35,6 @@ div.configuration-squeeze {
 }
 
 /* Container theming. */
-div.feeds-container {
-}
-
 div.feeds-container h4 {
   font-size: 1.2em;
   font-weight: bold;
@@ -95,11 +89,5 @@ ul.container-actions .form-item,
 ul.container-actions li form,
 ul.container-actions li form input {
   padding: 0;
-  margin: 0;
   display: inline;
 }
-
-/* Mapping form. */
-#center table form {
-  margin: 0;
-}
diff --git a/src/EventSubscriber/PubSubHubbub.php b/src/EventSubscriber/PubSubHubbub.php
index 80e6666..288412a 100644
--- a/src/EventSubscriber/PubSubHubbub.php
+++ b/src/EventSubscriber/PubSubHubbub.php
@@ -50,6 +50,9 @@ class PubSubHubbub implements EventSubscriberInterface {
 
   /**
    * Subscribes to a feed.
+   *
+   * @param \Drupal\feeds\Event\FetchEvent $event
+   *   The fetch event.
    */
   public function onPostFetch(FetchEvent $event) {
     $feed = $event->getFeed();
@@ -110,12 +113,12 @@ class PubSubHubbub implements EventSubscriberInterface {
   }
 
   /**
-   * ???
+   * Subscribes a subscription to a hub in a batch.
    *
    * @param \Drupal\feeds\FeedInterface $feed
-   *   ???
+   *   The feed to which the subscription is linked.
    * @param \Drupal\feeds\SubscriptionInterface $subscription
-   *   ???
+   *   The subscription to subscribe.
    */
   protected function subscribe(FeedInterface $feed, SubscriptionInterface $subscription) {
     $subscription->subscribe();
@@ -134,12 +137,12 @@ class PubSubHubbub implements EventSubscriberInterface {
   }
 
   /**
-   * ???
+   * Unsubscribes a subscription from a hub in a batch.
    *
    * @param \Drupal\feeds\FeedInterface $feed
-   *   ???
+   *   The feed to which the subscription is linked.
    * @param \Drupal\feeds\SubscriptionInterface $subscription
-   *   ???
+   *   The subscription to unsubscribe.
    */
   protected function unsubscribe(FeedInterface $feed, SubscriptionInterface $subscription = NULL) {
     if (!$subscription) {
@@ -162,10 +165,15 @@ class PubSubHubbub implements EventSubscriberInterface {
   }
 
   /**
-   * ???
+   * Subscribes to or unsubscribes from a hub.
+   *
+   * This method is used as callback for a batch.
    *
    * @param \Drupal\feeds\SubscriptionInterface $subscription
-   *   ???
+   *   The subscription entity.
+   *
+   * @see ::subscribe
+   * @see ::unsubscribe
    */
   public static function runSubscribeBatch(SubscriptionInterface $subscription) {
     switch ($subscription->getState()) {
@@ -268,6 +276,9 @@ class PubSubHubbub implements EventSubscriberInterface {
 
   /**
    * Deletes subscriptions when feeds are deleted.
+   *
+   * @param \Drupal\feeds\Event\DeleteFeedsEvent $event
+   *   The delete event.
    */
   public function onDeleteMultipleFeeds(DeleteFeedsEvent $event) {
     $subscriptions = $this->storage->loadMultiple(array_keys($event->getFeeds()));
diff --git a/src/FeedForm.php b/src/FeedForm.php
index 01e579c..16c39ac 100644
--- a/src/FeedForm.php
+++ b/src/FeedForm.php
@@ -265,11 +265,13 @@ class FeedForm extends ContentEntityForm {
    * @param \Drupal\feeds\Plugin\Type\FeedsPluginInterface $plugin
    *   The Feeds plugin.
    * @param string $operation
-   *   The type of form to check for. See \Drupal\feeds\Plugin\PluginFormFactory::hasForm()
-   *   for more information.
+   *   The type of form to check for. See
+   *   \Drupal\feeds\Plugin\PluginFormFactory::hasForm() for more information.
    *
    * @return bool
    *   True if the plugin implements a form of the given type. False otherwise.
+   *
+   * @see \Drupal\feeds\Plugin\PluginFormFactory::hasForm()
    */
   protected function pluginHasForm(FeedsPluginInterface $plugin, $operation) {
     return $this->formFactory->hasForm($plugin, $operation);
diff --git a/src/FeedTypeForm.php b/src/FeedTypeForm.php
index d0783b8..8b72dcb 100644
--- a/src/FeedTypeForm.php
+++ b/src/FeedTypeForm.php
@@ -368,11 +368,13 @@ class FeedTypeForm extends EntityForm {
    * @param \Drupal\feeds\Plugin\Type\FeedsPluginInterface $plugin
    *   The Feeds plugin.
    * @param string $operation
-   *   The type of form to check for. See \Drupal\feeds\Plugin\PluginFormFactory::hasForm()
-   *   for more information.
+   *   The type of form to check for. See
+   *   \Drupal\feeds\Plugin\PluginFormFactory::hasForm() for more information.
    *
    * @return bool
    *   True if the plugin implements a form of the given type. False otherwise.
+   *
+   * @see \Drupal\feeds\Plugin\PluginFormFactory::hasForm()
    */
   protected function pluginHasForm(FeedsPluginInterface $plugin, $operation) {
     return $this->formFactory->hasForm($plugin, $operation);
diff --git a/src/Feeds/Fetcher/Form/HttpFetcherFeedForm.php b/src/Feeds/Fetcher/Form/HttpFetcherFeedForm.php
index 5c177ab..7936df7 100644
--- a/src/Feeds/Fetcher/Form/HttpFetcherFeedForm.php
+++ b/src/Feeds/Fetcher/Form/HttpFetcherFeedForm.php
@@ -105,6 +105,7 @@ class HttpFetcherFeedForm extends ExternalPluginFormBase implements ContainerInj
    *
    * @param string $url
    *   The URL to GET.
+   *
    * @return \Guzzle\Http\Message\Response
    *   A Guzzle response.
    *
diff --git a/src/Feeds/Fetcher/HttpFetcher.php b/src/Feeds/Fetcher/HttpFetcher.php
index 3167e15..33eda49 100644
--- a/src/Feeds/Fetcher/HttpFetcher.php
+++ b/src/Feeds/Fetcher/HttpFetcher.php
@@ -86,7 +86,9 @@ class HttpFetcher extends PluginBase implements ClearableInterface, FetcherInter
 
     $response = $this->get($feed->getSource(), $sink, $this->getCacheKey($feed));
     // @todo Handle redirects.
+    // @codingStandardsIgnoreStart
     // $feed->setSource($response->getEffectiveUrl());
+    // @codingStandardsIgnoreEnd
 
     // 304, nothing to see here.
     if ($response->getStatusCode() == Response::HTTP_NOT_MODIFIED) {
diff --git a/src/Plugin/PluginFormFactory.php b/src/Plugin/PluginFormFactory.php
index b1ef9e7..602937d 100644
--- a/src/Plugin/PluginFormFactory.php
+++ b/src/Plugin/PluginFormFactory.php
@@ -40,8 +40,8 @@ class PluginFormFactory {
    *   - feed
    *     Displayed on the feed add/edit form.
    *   - option
-   *     A small form to appear on the plugin select box. The entity processor plugins
-   *     use this to display a form for selecting an entity bundle.
+   *     A small form to appear on the plugin select box. The entity processor
+   *     plugins use this to display a form for selecting an entity bundle.
    *
    * @return bool
    *   True if the plugin implements a form of the given type. False otherwise.
diff --git a/src/Plugin/Type/PluginBase.php b/src/Plugin/Type/PluginBase.php
index 52bab60..b7e8dab 100644
--- a/src/Plugin/Type/PluginBase.php
+++ b/src/Plugin/Type/PluginBase.php
@@ -131,11 +131,13 @@ abstract class PluginBase extends DrupalPluginBase implements FeedsPluginInterfa
   /**
    * Renders a link to a route given a route name and its parameters.
    *
+   * See \Drupal\Core\Utility\LinkGeneratorInterface::generate() for details
+   * on the arguments, usage, and possible exceptions.
+   *
    * @return string
    *   An HTML string containing a link to the given route and parameters.
    *
-   * @see \Drupal\Core\Utility\LinkGeneratorInterface::generate() for details
-   *   on the arguments, usage, and possible exceptions.
+   * @see \Drupal\Core\Utility\LinkGeneratorInterface::generate()
    */
   protected function l($text, $route_name, array $parameters = [], array $options = []) {
     return $this->linkGenerator()->generate($text, $route_name, $parameters, $options);
@@ -144,11 +146,13 @@ abstract class PluginBase extends DrupalPluginBase implements FeedsPluginInterfa
   /**
    * Generates a URL or path for a specific route based on the given parameters.
    *
+   * See \Drupal\Core\Routing\UrlGeneratorInterface::generateFromRoute() for
+   * details on the arguments, usage, and possible exceptions.
+   *
    * @return string
    *   The generated URL for the given route.
    *
-   * @see \Drupal\Core\Routing\UrlGeneratorInterface::generateFromRoute() for
-   *   details on the arguments, usage, and possible exceptions.
+   * @see \Drupal\Core\Routing\UrlGeneratorInterface::generateFromRoute()
    */
   protected function url($route_name, $route_parameters = [], $options = []) {
     return $this->urlGenerator()->generateFromRoute($route_name, $route_parameters, $options);
diff --git a/tests/src/Unit/FeedsUnitTestCase.php b/tests/src/Unit/FeedsUnitTestCase.php
index c60bd69..d4e0058 100644
--- a/tests/src/Unit/FeedsUnitTestCase.php
+++ b/tests/src/Unit/FeedsUnitTestCase.php
@@ -185,7 +185,7 @@ namespace {
   if (!function_exists('_format_date_callback')) {
 
     /**
-     *
+     * Stub for _format_date_callback() function.
      */
     function _format_date_callback(array $matches = NULL, $new_langcode = NULL) {
       // We cache translations to avoid redundant and rather costly calls to
@@ -222,19 +222,25 @@ namespace {
   }
 
   /**
-   *
+   * Stub for a filter format entity.
    */
   class FeedsFilterStub {
 
     /**
+     * Constructs a new FeedsFilterStub.
      *
+     * @param string $label
+     *   The filter's label.
      */
     public function __construct($label) {
       $this->label = $label;
     }
 
     /**
+     * Returns the filter's label.
      *
+     * @return string
+     *   The label of this filter.
      */
     public function label() {
       return $this->label;