diff --git a/core/lib/Drupal/Core/Render/Element/HtmlTag.php b/core/lib/Drupal/Core/Render/Element/HtmlTag.php
index f2bcacf..6aa3ca6 100644
--- a/core/lib/Drupal/Core/Render/Element/HtmlTag.php
+++ b/core/lib/Drupal/Core/Render/Element/HtmlTag.php
@@ -16,6 +16,23 @@
 /**
  * Provides a render element for any HTML tag, with properties and value.
  *
+ * Properties:
+ * - #tag: The tag name to output.
+ * - #attributes: (optional) An array of HTML attributes to apply to the
+ *   tag. The attributes are escaped, see \Drupal\Core\Template\Attribute.
+ * - #value: (optional) A string containing the textual contents of the tag.
+ * - #noscript: (optional) A boolean value. When set to TRUE, the markup
+ *   (including any prefix or suffix) will be wrapped in a <noscript> element.
+ *
+ * Usage Example:
+ * @code
+ * $build['hello'] = [
+ *   '#type' => 'html_tag'
+ *   '#tag' => 'p',
+ *   '#value' => $this->t('Hello World'),
+ * ];
+ * @endcode
+ *
  * @RenderElement("html_tag")
  */
 class HtmlTag extends RenderElement {
diff --git a/core/lib/Drupal/Core/Render/Element/InlineTemplate.php b/core/lib/Drupal/Core/Render/Element/InlineTemplate.php
index 7d2d553..90a3476 100644
--- a/core/lib/Drupal/Core/Render/Element/InlineTemplate.php
+++ b/core/lib/Drupal/Core/Render/Element/InlineTemplate.php
@@ -10,6 +10,22 @@
 /**
  * Provides a render element where the user supplies an in-line Twig template.
  *
+ * Properties:
+ * - #template: The inline twig template used to render the element.
+ * - #context: An array The variables available for use in the twig template.
+ *   Variable contents may be a render array.
+ *
+ * Usage Exmaple:
+ * @code
+ * $build['hello']  = [
+ *   '#type' => 'inline_template',
+ *   '#template' => "{% trans %} Hello {% endtrans %} <strong>{{name}}</strong>",
+ *   '#context' => [
+ *     'name' => $name,
+ *   ]
+ * ];
+ * @endcode
+ *
  * @RenderElement("inline_template")
  */
 class InlineTemplate extends RenderElement {
diff --git a/core/lib/Drupal/Core/Render/Element/Label.php b/core/lib/Drupal/Core/Render/Element/Label.php
index 7f90605..5406044 100644
--- a/core/lib/Drupal/Core/Render/Element/Label.php
+++ b/core/lib/Drupal/Core/Render/Element/Label.php
@@ -11,7 +11,8 @@
  * Provides a render element for displaying the label for a form element.
  *
  * Labels are generated automatically from element properties during processing
- * of most form elements.
+ * of most form elements.  This element is used internally by the form system
+ * to render labels for form elements.
  *
  * @RenderElement("label")
  */
diff --git a/core/lib/Drupal/Core/Render/Element/Link.php b/core/lib/Drupal/Core/Render/Element/Link.php
index 8f908d2..c1df4ad 100644
--- a/core/lib/Drupal/Core/Render/Element/Link.php
+++ b/core/lib/Drupal/Core/Render/Element/Link.php
@@ -15,6 +15,13 @@
 /**
  * Provides a link render element.
  *
+ * Properties:
+ * - #title: The link text.
+ * - #url: \Drupal|Url object containing information pointing to a routed or
+ *   non-routed path.
+ * - #options: (optional) An array of options to pass to the link generator.
+ *   see \Drupal\Core\Utility\LinkGeneratorInterface
+ *
  * @RenderElement("link")
  */
 class Link extends RenderElement {
diff --git a/core/lib/Drupal/Core/Render/Element/MoreLink.php b/core/lib/Drupal/Core/Render/Element/MoreLink.php
index 995c707..01d45ad 100644
--- a/core/lib/Drupal/Core/Render/Element/MoreLink.php
+++ b/core/lib/Drupal/Core/Render/Element/MoreLink.php
@@ -10,6 +10,14 @@
 /**
  * Provides a link render element for a "more" link, like those used in blocks.
  *
+ * Usage Example:
+ * @code
+ * $build['more'] = [
+ *   '#type' => 'more_link',
+ *   '#url' => Url::fromRoute('examples.more_examples')
+ * ]
+ * @endcode
+ *
  * @RenderElement("more_link")
  */
 class MoreLink extends Link {
diff --git a/core/lib/Drupal/Core/Render/Element/Pager.php b/core/lib/Drupal/Core/Render/Element/Pager.php
index 8e87cca..721e4ef 100644
--- a/core/lib/Drupal/Core/Render/Element/Pager.php
+++ b/core/lib/Drupal/Core/Render/Element/Pager.php
@@ -12,6 +12,28 @@
 /**
  * Provides a render element for a pager.
  *
+ * The pager must be initialized with a call to pager_default_initialize() in
+ * order to render properly. When used with database queries, this is performed
+ * for you when you extend a select query with
+ * \Drupal\Core\Database\Query\PagerSelectExtender.
+ *
+ * Properties:
+ * - #element: The pager ID, to distinguish bewteen multiple pagers on the same
+ *   page (defaults to 0).
+ * - #parameters: An associative array of query string parameters to append to
+ *   the pager.
+ * - #quantity: The number of pages in the list.
+ * - #tags: An array of labels for the controls in the pages.
+ * - #route_name: The name of the route to be used to build pager links. By
+ *   default no path is provided which will make links relative to the current
+ *   URL.  This makes the page more effectively cacheable.
+ *
+ * @code
+ * $build['pager'] = [
+ *   '#type' => 'pager',
+ * ];
+ * @endcode
+ *
  * @RenderElement("pager")
  */
 class Pager extends RenderElement{
diff --git a/core/lib/Drupal/Core/Render/Element/StatusMessages.php b/core/lib/Drupal/Core/Render/Element/StatusMessages.php
index 4153849..e62966f 100644
--- a/core/lib/Drupal/Core/Render/Element/StatusMessages.php
+++ b/core/lib/Drupal/Core/Render/Element/StatusMessages.php
@@ -10,6 +10,15 @@
 /**
  * Provides a messages element.
  *
+ * Used to display results of drupal_set_message() calls.
+ *
+ * Example Usage:
+ * @code
+ * $build['status_messages'] = [
+ *   '#type' => 'status_messages',
+ * ];
+ * @end
+ *
  * @RenderElement("status_messages")
  */
 class StatusMessages extends RenderElement {
diff --git a/core/lib/Drupal/Core/Render/Element/SystemCompactLink.php b/core/lib/Drupal/Core/Render/Element/SystemCompactLink.php
index fa701b0..b6740a0 100644
--- a/core/lib/Drupal/Core/Render/Element/SystemCompactLink.php
+++ b/core/lib/Drupal/Core/Render/Element/SystemCompactLink.php
@@ -13,6 +13,16 @@
 /**
  * Provides a link render element to show or hide inline help descriptions.
  *
+ * Descriptions are only hidden in system administration pages.
+ *
+ * Usage Example:
+ * @code
+ * $form['system_compact_link'] = [
+ *   '#id' => FALSE,
+ *   '#type' => 'system_compact_link',
+ * ];
+ * @endcode
+ *
  * @RenderElement("system_compact_link")
  */
 class SystemCompactLink extends Link {