+ * @param array $commentdata {
+ * Array of arguments for inserting a new comment.
+ *
+ * @type string $comment_agent The HTTP user agent of the `$comment_author` when
+ * the comment was submitted. Default empty.
+ * @type int|string $comment_approved Whether the comment has been approved. Default 1.
+ * @type string $comment_author The name of the author of the comment. Default empty.
+ * @type string $comment_author_email The email address of the `$comment_author`. Default empty.
+ * @type string $comment_author_IP The IP address of the `$comment_author`. Default empty.
+ * @type string $comment_author_url The URL address of the `$comment_author`. Default empty.
+ * @type string $comment_content The content of the comment. Default empty.
+ * @type string $comment_date The date the comment was submitted. To set the date
+ * manually, `$comment_date_gmt` must also be specified.
+ * Default is the current time.
+ * @type string $comment_date_gmt The date the comment was submitted in the GMT timezone.
+ * Default is `$comment_date` in the site's GMT timezone.
+ * @type int $comment_karma The karma of the comment. Default 0.
+ * @type int $comment_parent ID of this comment's parent, if any. Default 0.
+ * @type int $comment_post_ID ID of the post that relates to the comment, if any.
+ * Default empty.
+ * @type string $comment_type Comment type. Default empty.
+ * @type int $user_id ID of the user who submitted the comment. Default 0.
+ * }
+ * @return int|false The new comment's ID on success, false on failure.