What is agent identity?

Agent identity is the verifiable identity assigned to an AI agent, a non-human actor that calls tools and systems. It is a form of workload identity. A workload is a single piece of software deployed for a single purpose, and its identity is a string that uniquely identifies it.

Identity is not authentication, and it is not authorization. Identity is the "who". Authentication proves the "who" is genuine. Authorization grants what that "who" may do. The three are separate steps.

There are two broad kinds of identity. Human identities belong to people. Machine or non-human identities belong to devices and workloads. Agent identity is a non-human identity.

Why AI agents need their own identity

AI agents need separate identities because they act independently on systems and resources. If multiple agents share the same service account or use a human user's credentials, it becomes difficult to determine which agent performed an action.

A separate identity makes it possible to:

• Attribute actions: Logs can show which agent performed an action and on whose behalf.
• Apply least privilege: Each agent can receive only the permissions required for its task.
• Revoke access independently: Access can be removed from one agent without affecting other agents or the user it acts for.
• Investigate incidents: Security teams can trace actions back to a specific agent and its activity.

An agent may act on behalf of a user, but it remains a separate actor and should be identifiable as one.

How agent identity works

Agent identity is issued, then verified, then carried. The Secure Production Identity Framework for Everyone (SPIFFE) standard defines how a workload proves its identity. A SPIFFE ID is a string that uniquely identifies a workload, and an SPIFFE Verifiable Identity Document (SVID) is the document that proves it.

The identity document is short lived and rotated automatically. A workload can request a new identity document before the current one expires, and it does not need to hold a long-lived secret to do so.

Here is the illustration of how agent identity work:
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Attestation comes before authentication. Authentication asks whether an agent is who it claims to be. Attestation asks whether the workload is running in the environment it claims, executing the code it claims. Both questions need answers before access is granted.

The identity is then carried through the call chain. When an agent acts for a user, downstream services need two facts: which agent is acting, and which user authorised the action. This is a blended identity. The agent's workload identity and the user's authorisation context travel together.

Agent identity vs user identity

User identity represents a person, while agent identity represents a non-human workload acting independently or on a user's behalf.

How to manage agent identity

Managing agent identity requires strict isolation and continuous verification.

1. Give every agent a unique identity

Giving every agent a unique, verifiable identity scoped to its workload context is essential. Organizations must never reuse a shared service account across multiple agents.

2. Use runtime attestation

Using runtime attestation is more secure than relying solely on deployment time configuration. Systems must verify the workload is exactly what it claims to be each time it presents itself.

3. Issue temporary credentials

Issuing temporary credentials scoped to a specific task ensures tight security. Systems should let these credentials expire when the task completes rather than leaving them standing indefinitely.

4. Authenticate at every service boundary

Authenticating at every service boundary enforces strict access control. Systems must never rely on assumed network trust once an agent crosses from one environment into another.

5. Preserve the user identity context

Preserving the user identity and authorization context is critical when an agent acts on behalf of a human user. A user with only read access must never be allowed to trigger a write operation by passing instructions through a more privileged agent.

6. Log every agent action

Logging every agent action requires capturing enough context to fully reconstruct any event. Security logs must detail exactly who initiated the request, which agent acted, and what access level was used.

Related terms

• Agent authentication: proving who an agent is, the step that follows identity.
• Agent authorization: deciding what an agent may do, the step that follows authentication.
• Non-human identity: the broader category agent identity belongs to, alongside device and workload identities.
  Conclusion

Agent identity is the foundation every agent permission rests on. A user identity is a person, an agent identity is a workload. Give each agent its own verifiable identity, attest it at runtime, and carry the user's context alongside it. An agent that cannot be identified cannot be held accountable.

Frequently Ask Questions

1. What is agent identity?

Agent identity is the verifiable, non-human identity an AI agent carries when it acts on systems. It is distinct from the human user who may have triggered the agent.

2. Why do AI agents need their own identity?

Agents need their own identity so the audit trail shows which agent acted, not just that a shared account acted. A per-agent identity also enables least privilege and attribution.

3. What is the difference between agent identity and user identity?

A user identity is a person. An agent identity is a non-human workload. The agent may act for a person, but it is a distinct actor with its own identity and credentials.

4. How does agent identity relate to authentication and authorization?

Identity is the "who". Authentication proves the "who" is genuine. Authorization grants what that "who" may do. The three are separate steps, in that order.

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