WordPress at a glance
filter is not described

wp_die_json_handler filter-hook . WP 5.1.0

Filters the callback for killing WordPress execution for JSON requests.

Usage

add_filter( 'wp_die_json_handler', 'filter_function_name_482' );
function filter_function_name_482( $function ){
	// filter...

	return $function;
}
$function(callable)
Callback function name.

Where the hook is called

wp_die()
wp_die_json_handler
wp-includes/functions.php 2991
$function = apply_filters( 'wp_die_json_handler', '_json_wp_die_handler' );

Where the hook is used (in WP core)

Does not used.