WordPress at Your Fingertips
action is not described

woocommerce_flush_rewrite_rules action-hook . WC 1.0

Usage

add_action( 'woocommerce_flush_rewrite_rules', 'action_function_name_5254' );
function action_function_name_5254(){
	// action...
}

Where the hook is called

WC_Install::install()
woocommerce_flush_rewrite_rules
flush_rewrite_rules_on_shop_page_save()
woocommerce_flush_rewrite_rules
woocommerce/includes/class-wc-install.php 325
do_action( 'woocommerce_flush_rewrite_rules' );
woocommerce/includes/wc-core-functions.php 1153
do_action( 'woocommerce_flush_rewrite_rules' );

Where in WP core the hook is used WooCommerce

woocommerce/includes/class-wc-post-types.php 29
add_action( 'woocommerce_flush_rewrite_rules', array( __CLASS__, 'flush_rewrite_rules' ) );