diff --git a/wp-admin/includes/class-wp-ms-sites-list-table.php b/wp-admin/includes/class-wp-ms-sites-list-table.php
index 4bad0d87a5..f9b33e424f 100644
--- a/wp-admin/includes/class-wp-ms-sites-list-table.php
+++ b/wp-admin/includes/class-wp-ms-sites-list-table.php
@@ -156,6 +156,14 @@ class WP_MS_Sites_List_Table extends WP_List_Table {
 		if ( has_filter( 'wpmublogsaction' ) )
 			$sites_columns['plugins'] = __( 'Actions' );
 
+		/**
+		 * Filter the displayed site columns in Sites list table.
+		 *
+		 * @since MU
+		 *
+		 * @param array $sites_columns An array of displayed site columns. Default 'cb',
+		 *                             'blogname', 'lastupdated', 'registered', 'users'.
+		 */
 		$sites_columns = apply_filters( 'wpmu_blogs_columns', $sites_columns );
 
 		return $sites_columns;
@@ -275,6 +283,21 @@ class WP_MS_Sites_List_Table extends WP_List_Table {
 
 							$actions['visit']	= "<span class='view'><a href='" . esc_url( get_home_url( $blog['blog_id'], '/' ) ) . "' rel='permalink'>" . __( 'Visit' ) . '</a></span>';
 
+							/**
+							 * Filter the action links displayed for each site in the Sites list table.
+							 *
+							 * The 'Edit', 'Dashboard', 'Delete', and 'Visit' links are displayed by
+							 * default for each site. The site's status determines whether to show the
+							 * 'Activate' or 'Deactivate' link, 'Unarchive' or 'Archive' links, and
+							 * 'Not Spam' or 'Spam' link for each site.
+							 *
+							 * @since 3.1.0
+							 *
+							 * @param array  $actions  An array of action links to be displayed.
+							 * @param int    $blog_id  The site ID.
+							 * @param string $blogname Site path, formatted depending on whether it is a sub-domain
+							 *                         or subdirectory multisite install.
+							 */
 							$actions = apply_filters( 'manage_sites_action_links', array_filter( $actions ), $blog['blog_id'], $blogname );
 							echo $this->row_actions( $actions );
 					?>
@@ -328,6 +351,15 @@ class WP_MS_Sites_List_Table extends WP_List_Table {
 				case 'plugins': ?>
 					<?php if ( has_filter( 'wpmublogsaction' ) ) {
 					echo "<td valign='top' class='$column_name column-$column_name'$style>";
+						/**
+						 * Fires inside the auxiliary 'Actions' column of the Sites list table.
+						 *
+						 * By default this column is hidden unless something is hooked to the action.
+						 *
+						 * @since MU
+						 *
+						 * @param int $blog_id The site ID.
+						 */
 						do_action( 'wpmublogsaction', $blog['blog_id'] ); ?>
 					</td>
 					<?php }
@@ -335,6 +367,14 @@ class WP_MS_Sites_List_Table extends WP_List_Table {
 
 				default:
 					echo "<td class='$column_name column-$column_name'$style>";
+					/**
+					 * Fires for each registered custom column in the Sites list table.
+					 *
+					 * @since 3.1.0
+					 *
+					 * @param string $column_name The name of the column to display.
+					 * @param int    $blog_id     The site ID.
+					 */
 					do_action( 'manage_sites_custom_column', $column_name, $blog['blog_id'] );
 					echo "</td>";
 					break;