diff --git a/src/wp-admin/includes/file.php b/src/wp-admin/includes/file.php
index 2f90b74dbd..ee0536e647 100644
--- a/src/wp-admin/includes/file.php
+++ b/src/wp-admin/includes/file.php
@@ -958,14 +958,15 @@ function wp_handle_sideload( &$file, $overrides = false, $time = null ) {
 
 
 /**
- * Downloads a URL to a local temporary file using the WordPress HTTP Class.
- * Please note, That the calling function must unlink() the file.
+ * Downloads a URL to a local temporary file using the WordPress HTTP API.
+ *
+ * Please note that the calling function must unlink() the file.
  *
  * @since 2.5.0
  *
- * @param string $url the URL of the file to download
- * @param int $timeout The timeout for the request to download the file default 300 seconds
- * @return mixed WP_Error on failure, string Filename on success.
+ * @param string $url  The URL of the file to download.
+ * @param int $timeout The timeout for the request to download the file. Default 300 seconds.
+ * @return string|WP_Error Filename on success, WP_Error on failure.
  */
 function download_url( $url, $timeout = 300 ) {
 	//WARNING: The file is not automatically deleted, The script must unlink() the file.