Google I/O opens today, and most of the coverage will be about the demos. The more interesting story is the protocol race happening underneath them. Six new agent protocols have launched in the past year, and if you are building or buying agents right now, the standards layer reads like a scrum.The instinct is to ignore the acronyms and wait for the big platforms to absorb everything behind product surfaces. The platforms will absorb a lot of it. But the protocols are not all trying to solve the same problem, and the substrate an agent is built on shapes the customer experience more than the model choice does. Read as a pile of competing standards, the picture stays blurry. Read as layers, three of them snap into focus as the foundation most builders will actually depend on.Three protocols are forming the core agent stack: MCP for the tools and data an agent can reach, A2A for the other agents it can delegate to, and AG-UI for the controls a human needs to stay in the loop while long-running work is happening. Those three answer the only three questions every real agent system hits within its first week of existence. What can the agent use. Who else can the agent work with. How does the human stay in control. A2UI, AP2, and x402 matter, but they sit in layers where product requirements, trust boundaries, payment rails, and platform incentives are still being negotiated. Treating those three as equal bets with the first three is the most common mistake I see in agent strategy decks right now.Builders who try to bet on all the layers at once end up paralyzed. Builders who ignore the layer map ship agents that fail at the boundaries that actually matter, like security on tool access, approval on long-running work, and supervision when the agent crosses company lines. Buyers who cannot read the layer map cannot evaluate what they are actually purchasing when a vendor says the word “agent.” The map is the closest thing the industry has to a shared vocabulary, and the next twelve months of agent product strategy will run through it.Here’s what’s inside:The protocol map. A single table that places all six protocols in the layer they actually occupy, so the acronyms stop blurring together.The core stack: MCP, A2A, AG-UI. Why these three are converging into the universal foundation, what each one is really for, and where each one fails if treated as a feature toggle instead of a boundary.Why payments are not one protocol. AP2 and x402 solve different problems, the payment space carries hidden assumptions about geography and authorization, and “agent can pay” is not a button — it is an audit problem.Map, draft, audit, brief. Map any real workflow to the layers that matter, draft the Agent Card boundary another team will integrate against, audit a workflow for the human controls it’s missing, and produce the strategy brief for the leader making the platform bet — four prompts, one per job, with renewal prep as the worked example threaded through.The acronym pile will keep growing. The layer map will not.