WordPress at a glance
action is not described

woocommerce_before_checkout_form_cart_notices action-hook . WC 1.0

Show non-cart errors.

Usage

add_action( 'woocommerce_before_checkout_form_cart_notices', 'action_function_name_4536' );
function action_function_name_4536(){
	// action...
}

Where the hook is called

WC_Shortcode_Checkout::checkout()
woocommerce_before_checkout_form_cart_notices
woocommerce/includes/shortcodes/class-wc-shortcode-checkout.php 264
do_action( 'woocommerce_before_checkout_form_cart_notices' );

Where in WP core the hook is used WooCommerce

woocommerce/includes/wc-template-hooks.php 308
add_action( 'woocommerce_before_checkout_form_cart_notices', 'woocommerce_output_all_notices', 10 );