IDENTITY AS INFRASTRUCTURE
We optimized for the wrong question.
The new version of AAuth (draft-hardt-aauth-protocol-01) materially changes the earlier comparison. Mission is now first-class in the protocol, with PS-mediated approval, mission-aware token choreography, and governance endpoints. The remaining gap is no longer whether Mission exists, but whether the published model is strong enough to support portable containment rather than just mission correlation and governance hooks.
ID-JAG, also often called Cross-App Access (XAA), is centered in the current draft on Enterprise IdP trust, but the issuer that matters is the immediate IdP the downstream authorization server already trusts for SSO and subject resolution, not necessarily the top-level workforce IdP. The same trust pattern can also extend architecturally to CIAM and platform identity layers that federate upstream workforce login while remaining authoritative for downstream product trust, tenant context, and subject resolution.
Open-world OAuth can improve discovery, resource binding, and first-contact trust. That still leaves the harder agent problem: how approved intent becomes bounded authority that stays governed across delegation chains, unfamiliar tools, consent expansion, revocation, and task termination.
OAuth was built for closed worlds, and that constraint is why it became mature. Agents expose the limits of that deployment model. This post traces what the newer OAuth standards get right and which substrate gaps still need to close.
The current split between token exchange semantics and JWT access token practice creates avoidable interoperability failures. A common profile for act, grounded in entity profiles, can align JWT assertion grant and JWT access token processing.
Part 2 turns from the semantic problem to the runtime one. Quiet expansion, delegation, headless execution, stale state, and open-world execution all push Mission shaping past its strongest domain. Containment and runtime governance carry more of the safety burden.
This essay picks up from Part 4 of the Mission-Bound OAuth series and focuses on the first hard problem: how approved intent becomes a governable Mission. In structured domains that can look like staged Mission shaping or compilation. Many current deployments still do not do it at all.
Mission-Bound OAuth is a serious attempt to govern delegated agent authority using existing OAuth infrastructure. This post takes the pessimistic view: it may be the wrong answer because it asks the authorization server to become a governance engine, a lifecycle controller, and a mission ledger all at once. A cleaner alternative is to treat Mission as a separate authority service and let OAuth be one projection of that model rather than its home.
Mission-Bound OAuth argues for a durable Mission object that governs delegated authority across approval, lifecycle, delegation, and termination. This follow-up asks whether Dick Hardt’s AAuth draft is a better protocol substrate for the same model, and where AAuth still appears to need an explicit Mission-like authority object.
Rich Authorization Requests are the natural first instinct for agent missions, but audience-bound access tokens and uneven cross-domain interoperability limit how far they can carry a governed task. Mission-Bound OAuth solves that by making the Mission a durable authority object at the authorization server. This post explores the authentication-layer companion profile: OpenID Connect Client Context carries purpose and approval input when the user is present, and ID-JAG carries reduced Mission projections across same-IdP trust domains.