WordPress at a glance
action is not described

pre_trackback_post action-hook . WP 4.7.0

Fires before the trackback is added to a post.

Usage

add_action( 'pre_trackback_post', 'action_function_name_2420', 10, 6 );
function action_function_name_2420( $tb_id, $tb_url, $charset, $title, $excerpt, $blog_name ){
	// action...
}
$tb_id(int)
Post ID related to the trackback.
$tb_url(string)
Trackback URL.
$charset(string)
Character Set.
$title(string)
Trackback Title.
$excerpt(string)
Trackback Excerpt.
$blog_name(string)
Blog Name.

Where the hook is called

In file: /wp-trackback.php
pre_trackback_post
wp-trackback.php 106
do_action( 'pre_trackback_post', $tb_id, $tb_url, $charset, $title, $excerpt, $blog_name );

Where the hook is used (in WP core)

Does not used.