diff --git a/core/includes/form.inc b/core/includes/form.inc
index ab2dd8c806c2d616f283506e4f12fbfc3e71bfdf..aea9af1faa5963346f9cb5adc333e7a11703a544 100644
--- a/core/includes/form.inc
+++ b/core/includes/form.inc
@@ -4503,13 +4503,24 @@ function _form_set_class(&$element, $class = array()) {
  */
 
 /**
- * Opens a new batch.
- *
- * @param $batch
- *   An array defining the batch. The following keys can be used -- only
- *   'operations' is required, and batch_init() provides default values for
- *   the messages.
- *   - 'operations': Array of function calls to be performed.
+ * Adds a new batch.
+ *
+ * Batch operations are added as new batch sets. Batch sets are used to spread
+ * processing (primarily, but not exclusively, forms processing) over several
+ * page requests. This helps to ensure that the processing is not interrupted
+ * due to PHP timeouts, while users are still able to receive feedback on the
+ * progress of the ongoing operations. Combining related operations into
+ * distinct batch sets provides clean code independence for each batch set,
+ * ensuring that two or more batches, submitted independently, can be processed
+ * without mutual interference. Each batch set may specify its own set of
+ * operations and results, produce its own UI messages, and trigger its own
+ * 'finished' callback. Batch sets are processed sequentially, with the progress
+ * bar starting afresh for each new set.
+ *
+ * @param $batch_definition
+ *   An associative array defining the batch, with the following elements (all
+ *   are optional except as noted):
+ *   - operations: (required) Array of function calls to be performed.
  *     Example:
  *     @code
  *     array(
@@ -4517,35 +4528,26 @@ function _form_set_class(&$element, $class = array()) {
  *       array('my_function_2', array($arg2_1, $arg2_2)),
  *     )
  *     @endcode
- *   - 'title': Title for the progress page. Only safe strings should be passed.
- *     Defaults to t('Processing').
- *   - 'init_message': Message displayed while the processing is initialized.
+ *   - title: A safe, translated string to use as the title for the progress
+ *     page. Defaults to t('Processing').
+ *   - init_message: Message displayed while the processing is initialized.
  *     Defaults to t('Initializing.').
- *   - 'progress_message': Message displayed while processing the batch.
- *     Available placeholders are @current, @remaining, @total, @percentage,
- *     @estimate and @elapsed. Defaults to t('Completed @current of @total.').
- *   - 'error_message': Message displayed if an error occurred while processing
+ *   - progress_message: Message displayed while processing the batch. Available
+ *     placeholders are @current, @remaining, @total, @percentage, @estimate and
+ *     @elapsed. Defaults to t('Completed @current of @total.').
+ *   - error_message: Message displayed if an error occurred while processing
  *     the batch. Defaults to t('An error has occurred.').
- *   - 'finished': Name of a function to be executed after the batch has
- *     completed. This should be used to perform any result massaging that
- *     may be needed, and possibly save data in $_SESSION for display after
- *     final page redirection.
- *   - 'file': Path to the file containing the definitions of the
- *     'operations' and 'finished' functions, for instance if they don't
- *     reside in the main .module file. The path should be relative to
- *     base_path(), and thus should be built using drupal_get_path().
- *   - 'css': Array of paths to CSS files to be used on the progress page.
- *   - 'url_options': options passed to url() when constructing redirect
- *     URLs for the batch.
- *
- * Operations are added as new batch sets. Batch sets are used to ensure
- * clean code independence, ensuring that several batches submitted by
- * different parts of the code (core / contrib modules) can be processed
- * correctly while not interfering or having to cope with each other. Each
- * batch set gets to specify its own UI messages, operates on its own set
- * of operations and results, and triggers its own 'finished' callback.
- * Batch sets are processed sequentially, with the progress bar starting
- * fresh for every new set.
+ *   - finished: Name of a function to be executed after the batch has
+ *     completed. This should be used to perform any result massaging that may
+ *     be needed, and possibly save data in $_SESSION for display after final
+ *     page redirection.
+ *   - file: Path to the file containing the definitions of the 'operations' and
+ *     'finished' functions, for instance if they don't reside in the main
+ *     .module file. The path should be relative to base_path(), and thus should
+ *     be built using drupal_get_path().
+ *   - css: Array of paths to CSS files to be used on the progress page.
+ *   - url_options: options passed to url() when constructing redirect URLs for
+ *     the batch.
  */
 function batch_set($batch_definition) {
   if ($batch_definition) {