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SpecificationsAAuth Protocol

AAuth Protocol

Status: Internet-Draft Spec: draft-hardt-aauth-protocol

The main authorization protocol built on the Headers layer. Defines the token types, endpoints, and flows that make up AAuth.

What It Does

Three Token Types

TokenIssued ByPurpose
Agent Token (agent+jwt)Agent ServerBinds a delegate’s key to the agent’s identity
Resource Token (resource+jwt)ResourceAccess challenge binding the request to the resource’s identity
Auth Token (auth+jwt)Auth ServerGrants access with user identity and scopes

Unified Token Endpoint

A single endpoint handles all authorization scenarios. When the response can’t be immediate, the server returns 202 Accepted with a Location header pointing to a pending URL. The agent polls until ready.

Key Features

  • Deferred responses202 Accepted + polling for any async flow
  • Clarification chat — users can ask the agent questions during consent
  • Call chaining — resources access downstream resources on behalf of the caller
  • Cross-domain AS federation — an agent’s AS can call a resource’s AS
  • Agent as audience — SSO and first-party access use the same flow
  • No refresh tokens — expired tokens + signatures are sufficient for renewal

Primitives provided: token issuance, federation, deferred authorization, user delegation

Read the Spec