You can validate addresses before creating labels in order to save costs and avoid getting charged by carriers for address correction. ShipEngine can validate addresses for the following countries: United States, Canada, Great Britain, Australia, Germany, France, Norway, Spain, Sweden, Israel, and Italy.
In the request, include the country code for the address you are validating. The response will include a status indicating whether the address was verified.
Then, to create a label for an international shipment, include the customs item in the request. In the JSON response, download the label (label_download.href) and any forms that are included (links.form_download). USPS customs forms come included with the label file.