Varwof.

AI Agent Identity Certificate (AIC)

An X.509 v3 extension that cryptographically binds an AI agent to the principal that authorizes it — with authorization that can be verified entirely offline.

Certificate as Identity · Certificate as Authority · Certificate as Policy

IETF Experimental Draft draft-wei-aic-identity-cert-00 — Published IANA PEN 66257

// What is AIC?

AIC extends X.509 v3 certificates so that an AI agent carries its identity, its binding to the authorizing principal, its declared capabilities, and cryptographic evidence of delegation in a single certificate. It separates cryptographic delegation from authorization semantics: the certificate defines the binding, while capability semantics are defined externally by schemes.

The design goal is offline-verifiable authorization: a gateway can decide whether to admit an agent using only the certificate and its credential bundle, without external database lookups.

// The Questions AIC Answers

Who are you?

The certificate anchors the agent's cryptographic identity (agentId) through a standard X.509 chain.

Who authorized you?

principalUid binds the agent to the authorizing principal via an SPKI key hash.

Why were you authorized?

The delegation reason is signed by the principal inside the DelegationAuthorization, for audit and compliance.

What are you authorized to do?

Structured capabilities (schemeId / capabilityId) declare the operations the agent may perform.

What can you do at execution?

Gateways route each requested operation to the plugin registered for its scheme, offline and without external lookups.

What are your limits?

authorizationConstraints carry offline-verifiable boundaries: IP ranges, concurrency, and time windows.

// Key Features

Principal Binding

principalUid anchors the agent to the authorizing principal via an SPKI key hash, preserving identity across certificate renewals with the same key pair.

Delegation Evidence

A principal-signed DelegationAuthorization, covered by the CA signature, provides cryptographic evidence of authorization with replay protection.

Capability Container

Structured capabilities (schemeId / capabilityId) route evaluation to scheme-specific plugins without changing the certificate format.

Offline Verification

Authorization decisions are made offline at the gateway from the certificate and credential bundle alone — no external database required.

Authorization Constraints

Offline-verifiable boundary conditions (IP ranges, concurrency, time windows) limit the blast radius of a compromised agent.

Accountability

Cryptographic evidence supports attribution of agent actions to the authorizing principal, for audit and compliance processes.

// Documents

// Projects

types — Go SDK

Core protocol types, parsing, validation, capability matching, and SPKI key hashing. Zero dependencies. Public release planned.

register — Capability Registry

Machine-readable capability scheme definitions, signature protection, and minimal-permission tooling. Public release planned.

// Status

draft-wei-aic-identity-cert-00 — published 2026-08-20, IETF Experimental.

IPR: Royalty-Free licensing commitment.

Go reference implementation in development; repositories to be published.

// Contact

General: varwof@varwof.com
Standards & draft: pki@varwof.com