// AUTHORITY: VALID · ACTION: WITHIN_SCOPE
Definition
Proof of Actor is a proposed trust infrastructure for determining whether a digital interaction is being performed by a human, a human using AI, or an autonomous AI agent, and for establishing who authorised the action.
Where authentication ends
Proof of Actor begins where authentication ends.
These are different problems. Answering one does not answer the others.
Authentication answers
Can this entity access this account?
Identity answers
Who owns this identity?
Proof of Actor asks
Who or what is actually performing this action right now?
A person may authenticate successfully and then:
The Actor model
Four Actor states
An actor is the entity actually responsible for producing or controlling a digital interaction. Interactions resolve into four understandable states. None is universally better than another.
HUMAN
A human appears to be directly controlling the interaction.
A candidate completes an assessment personally without meaningful external AI assistance.
HUMAN + AI
A human remains responsible for the interaction, but AI materially assists.
A professional writes an email while using an AI writing assistant. Depending on context, entirely acceptable.
AUTHORISED AGENT
An AI agent performs the interaction on behalf of an identified human or organisation, within delegated authority.
A shopping agent authorised by its user purchases a flight within a specified budget.
UNVERIFIED ACTOR
The service cannot establish the actor, human control or accountable principal with sufficient confidence.
This does not automatically mean malicious. It means: trust relationship unknown.
Contextual trust
Proof of Actor provides the evidence. The relying service decides the policy.
Different contexts require different policies. The same evidence can lead to different, equally correct decisions.
| Context | May require or allow |
|---|---|
| Hiring assessment | HUMAN |
| Customer-support interaction | HUMAN or AUTHORISED AGENT |
| Online marketplace | HUMAN, HUMAN + AI or AUTHORISED AGENT |
| Bank approving a major transfer | Verified human identity + current human presence + explicit human intent |
The Proof of Actor Trust Stack
Ten questions behind every consequential interaction
Proof of Actor is designed to reason across distinct layers, so an application can request exactly the evidence its context needs.
Personhood
Is there evidence that a real human exists behind this interaction?
Different from identifying the human. A service can learn that a real person is there without learning who they are.
Identity
Is this human the person they claim to be?
Optional where anonymity or pseudonymity should be preserved. Designed to support "verified human, identity undisclosed".
Presence
Is the human actually present during this interaction?
Passing identity verification fifteen minutes earlier does not establish current presence.
Actor continuity
Is the same actor continuing throughout the session?
Addresses impersonation, hand-offs, remote assistance, session takeover and substitution.
Human control
Is the human actually controlling the interaction?
Authentication proves access. Identity proves identity. Presence proves presence. None of them necessarily proves control.
AI participation
Is AI materially participating in the interaction?
Graded, never binary: no meaningful AI signal, possible, probable or declared assistance, or autonomous agent activity.
Delegation
If an AI agent is acting, who authorised it?
The principal could be an individual, an organisation or another authorised service.
Scope of authority
What is this actor allowed to do?
Permissions, transaction limits, allowed counterparties, expiry and revocation, checked against the action requested now.
Intent
Did the human explicitly approve this action, at this time, under these conditions?
For consequential actions, standing authority alone may not be enough.
Accountability
Who ultimately stands behind this action?
Every meaningful attestation should make it possible to answer this question.
The protocol vision
A trust protocol applications query before relying on an actor
The largest version of Proof of Actor is not another verification API. It is a trust protocol applications can request during meaningful interactions, receiving an Actor Attestation and enforcing their own rules.
// Proposed API - illustrative only
policy.require({
actor: "human",
presence: "continuous",
control: 0.90,
aiAssistance: "low"
});
// Or, for a service that welcomes authorised agents:
policy.allow({
actor: ["human", "authorized_agent"],
agentAuthority: {
required: true
}
});Who is acting?
Applications then enforce their own rules.
Architecture philosophy
Designed to be
We publish what Proof of Actor establishes. We are deliberately selective about how: scoring, signal weightings and detection techniques stay private.
Signal-agnostic
Not tied permanently to a webcam, biometrics or any single technique.
Multi-signal
Trust emerges from independent evidence rather than one fragile check.
Continuous
High-value interactions are verified throughout the session, not only at login.
Contextual
The evidence required to comment on a forum differs from the evidence required to move $1 million.
Privacy-aware
Collect the minimum information required for the requested claim.
Explainable
Applications receive the evidence behind a trust outcome, not just a label.
Revocable
Agent authority must always be withdrawable.
Auditable
Consequential attestations produce reliable records.
Developer-first
Integration should become easier than building internal verification infrastructure.
FAQ
Questions about how Proof of Actor works
What is Proof of Actor?
Proof of Actor is a proposed trust infrastructure for determining whether a digital interaction is being performed by a human, a human using AI, or an autonomous AI agent, and for establishing who authorised the action. It is in development.
What is an actor?
An actor is the entity actually responsible for producing or controlling a digital interaction. It may be a human, a human assisted by AI, an authorised AI agent acting for a principal, or an actor the service cannot verify.
Is Proof of Actor bot detection?
No. Bot detection asks whether traffic looks automated. Proof of Actor asks who or what is acting, whether a human is present and in control, whether AI is involved and who authorised the action. Bot signals may become inputs, but they do not describe the problem.
Who decides whether an actor is acceptable?
The relying application. Proof of Actor supplies trust evidence; the customer determines acceptable policy. A hiring assessment, a support chat and a bank transfer can require very different things.
Why not just block all AI?
Because AI participation is often legitimate and increasingly unavoidable. The problem is not that AI participates; it is when agency becomes invisible. Proof of Actor is designed to make AI attributable rather than to make it disappear.
Help define the Actor Trust Layer.
The protocol is being shaped with early design partners. Bring the interaction you cannot currently trust.