A2UI: the interface is the interruption, not the experience. A design framework for moments when autonomous AI agents must communicate with humans..
| Dimension | Traditional UX | Agentic Experience Design (AXD) |
|---|---|---|
| Primary material | Attention and affordance | Trust and delegation |
| User state | Present, navigating | Absent, delegating |
| Design output | Screens and interfaces | Outcomes and constraints |
| Temporal model | Session-based | Relationship-based |
| Success metric | Task completion | Trust calibration |
A2UI (Agent-to-User Interface) is the communication layer through which autonomous AI agents surface information, request decisions, and report outcomes to human users. Unlike traditional UI which responds to user input, A2UI is initiated by the agent when it needs human attention, making it a core component of Agentic Experience Design (AXD).
Traditional UIs are human-initiated: the user clicks, types, or navigates. A2UI is agent-initiated: the system determines when, how, and why to interrupt the human. This inversion means A2UI design must optimise for interrupt frequency, context delivery, and trust maintenance rather than navigation and discoverability.
In agentic commerce, AI agents act autonomously on behalf of users - purchasing, negotiating, and transacting. A2UI is the mechanism through which these agents communicate outcomes, escalate exceptions, and request re-authorisation. Without well-designed A2UI, users lose visibility into what their agents are doing, eroding trust in the entire agentic relationship.
A2UI (Agent-to-User Interface) is the communication layer through which autonomous AI agents surface information, request decisions, and report outcomes to human users. Unlike traditional UI which responds to user input, A2UI is initiated by the agent when it needs human attention, making it a core component of Agentic Experience Design (AXD).
Traditional UIs are human-initiated: the user clicks, types, or navigates. A2UI is agent-initiated: the system determines when, how, and why to interrupt the human. This inversion means A2UI design must optimise for interrupt frequency, context delivery, and trust maintenance rather than navigation and discoverability.
The Observatory · Issue 008 · September 2026 The Agent-to-User Interface: Designing the Narrowest Possible Opening There is a wall. It is vast, concrete, unbroken. It stretches in every direction - the wall of autonomous operation, of agents acting in the world without human involvement. And in this wall, there is a slit. Narrow. Precisely cut. Through it, a sliver of golden light falls into the space where the human stands. This slit is the Agent-to-User Interface. It is not a dashboard. It is not a control panel. It is not a conversation. It is the narrowest possible opening through which an autonomous system communicates with the human who In screen-based design, the interface was everything. The entire experience was the interface. Every pixel, every interaction, every moment of attention was mediated through a designed surface. The designer's job was to make that surface as rich, as intuitive, as engaging as possible. More interface meant more opportunity for design. In agentic design, the opposite is true. The best agent-to-user interface is the one that appears least often. The most successful agentic experience is the one where the slit in the wall is never needed - where the agent operates with such fidelity to the human's intent that no interruption is required. The interface is not the experience. The interface is the exception. A2UI - Agent-to-User Interface - is a term I propose for the specific, designed surface through which an autonomous agent communicates with the human principal who delegated authority to it. It is distinct from a traditional user interface in three fundamental ways. Every A2UI is, at its core, an interrupt. It breaks the human's absence - their state of not-attending-to-the-agent - and demands attention. This makes interrupt design the central discipline of A2UI, and it is a discipline that UX has never had to master at this level of consequence. In screen-based design, interrupts were notifications - and notificatio