The Interface Stack Has a Missing Layer

Google DeepMind just released a browser that generates entire websites from a single sentence. You type "a guide to watering my cheese plant," and Gemini 3.1 Flash-Lite writes a complete page — navigation, layout, content — in under two seconds. No server. No pre-built HTML. The page is born the moment you ask for it. The Flash-Lite Browser is a striking demo. But it also exposes a structural gap in how we think about agent interfaces. The industry is converging on an architecture — CLI for agents, protocols for communication, generated GUI for humans — but this three-layer stack is missing something critical. The Three-Layer Interface Stack A pattern is forming across the agent ecosystem. It looks like this: Bottom layer: CLI is the agent runtime. Agents operate through text commands — structured input, structured output, composable pipelines. This is their native language. Claude Code, GitHub Copilot CLI, and every MCP-connected agent speak CLI first. Middle layer: Protocols connect