Systems and methods for processing custom structured tags at a self-service terminal are disclosed. Custom structured tags received by a self-service terminal can include information to identify one or more devices attached to the terminal and identify one or more types of data to be obtained from a user by use of the attached devices. In some embodiments, a browser can natively interpret the custom structured tags. The self-service terminal can also be configured to receive and decode structured tags identifying or more actions to be performed by the device, such as printing a transaction record or dispensing currency.