Your AI Agent Has an OAuth Token. Does It Have an Identity?

OAuth can prove that a request may reach a resource. It does not, by itself, tell an operator the full story of the actor holding the token. That distinction matters once software can plan, call tools, retry, and act across several systems. The question is no longer only, "Is this request authenticated?" It is also: Which agent is acting? Under whose authority? For what purpose? Against which target? What evidence will remain after the action? If your system cannot answer those questions without reading the agent's prompt, it does not yet have an operational identity model. It has a credential. A token is permission, not the whole identity OAuth remains essential infrastructure for agents. The current Model Context Protocol authorization specification builds on OAuth 2.1, Protected Resource Metadata, Client ID Metadata Documents, audience binding, and least-privilege scopes. It also hardens issuer validation, defines step-up authorization, and forbids token passthrough. Those controls answer important questions: Is this token intended for this resource? Which permissions did the user approve? Has the credential expired? Does the resource server accept its audience? But a token is still one artifact inside a larger system. It can carry identity claims, but it does not automatically give that identity a lifecycle, an owner, a purpose, or a useful audit trail. An operational identity is the continuity around the token. It says this is the same agent before, during, and after a credential is issued, and that its authority can be understood and withdrawn. Borrowing a human identity breaks the record The fastest way to get an agent moving is often to lend it a human credential. Copy an API key into the environment. Reuse a browser session. Give it an access token created for an employee. Now the log says a person acted when an agent did. The credential may carry every permission the person has, even though the task needed two. Revoking the agent means revoking the human.