add more php docs

includes/base/class-transformer-base.php

@@ -23,6 +23,7 @@ abstract class Transformer_Base {
      * By default all post types are supported.
      * 
 	 * @since version_number_transformer_management_placeholder
+     * @return string[] An array containing all the supported post types.
 	 */
     public function get_supported_post_types() {
         return \get_post_types( array(), 'names');
@@ -32,6 +33,8 @@ abstract class Transformer_Base {
 	 * Get the name used for registering the transformer with the ActivityPub plugin.
 	 *
 	 * @since version_number_transformer_management_placeholder
+     * 
+     * @return string name
 	 */
     abstract public function get_name();
 
@@ -39,6 +42,8 @@ abstract class Transformer_Base {
 	 * Get the display name for the ActivityPub transformer.
 	 *
 	 * @since version_number_transformer_management_placeholder
+     * 
+     * @return string display name
 	 */
     abstract public function get_title();
 }