AI Agents now act on the web for millions of people. To a Site, an Agent can take many forms. It may be indistinguishable from a human user carrying out a task, or it might look like one visitor carrying many Users. This removes the ability for the Site to recognize, serve, and hold accountable the user or users behind the Agent, and causes the Site to face the costs when something goes wrong. This post argues that in order for Sites to maximize the access they provide to Agents, the ecosystem must develop new mechanisms to preserve the relationship between Sites and Users. Traditionally, in Security and Fraud Prevention, that requires three things: Identity, Reputation, and Accountability, allowing Sites to answer: Is the person acting being truthful about who they are? Is that person trustworthy? And who answers for the action?