The disclosed technology teaches testing with a test parameter data structure, applied to an AUT that operates in both API and UI mode, processing a configurable script to test in both modes. UI mode renders and interacts with UI elements utilizing values stored in the structure, used by the script in both modes, providing display mark-up in the script that is rendered in UI mode and formats fields to receive data that map to specific elements, leaving to be completed a mapping connection between the fields in the display and specific elements in the structure. The method includes providing a mapping of fields to elements, based on names, and while processing the script in UI mode, rendering the mark-up from the script, using a bot to interact with and complete the mark-up, applying the mapping to identify elements to complete fields, and causing processing of the fields in the mark-up.