Techniques for overlaying a custom interface onto an existing kiosk interface are provided. An event is detected that triggers a kiosk to process an agent that overlays, and without modifying, the kiosk's existing interface. The agent alters screen features and visual presentation of the existing interface and provides additional alternative operations for navigating and executing features defined in the existing interface. In an embodiment, the agent provides a custom interface overlaid onto the existing interface to provide a customer-facing interface for individuals that are sight impaired, and the method further comprises injecting non-visible tags into screen definitions for the existing interface that are recognized only by the agents to handle exception conditions and actively ignored by the existing interface.