Hi Warren,

Thank you for taking the time to read it, and fair point: the introduction is 
too abstract.

Some context: I come from the credential side.
In MCP and A2A, OAuth is the first-class mechanism, and from where I sit the 
goal is for credentials to fit into that as closely as possible.
OpenID4VP is excellent where a verifier needs to negotiate with a wallet, but 
that is not this use case.
What struck me is that a DPoP proof already has essentially the same structure 
as the key binding in a verifiable presentation, so an ordinary DPoP-capable 
resource server is, in effect, already a presentation verifier.

Concretely: a user delegates to an agent, and the agent calls several resource 
servers (e.g. MCP tool servers) in the same trust domain.
With access tokens, the agent needs a separate audience-restricted token for 
each resource server.

The draft lets the AS, or an IdP the resource servers already trust, issue one 
holder-bound credential that the agent presents to each resource server 
directly with DPoP, with revocation through a status list.
If the issuer sets aud, it is enforced as usual, and it can list the set of 
resource servers the credential is meant for.
If aud is omitted, the credential is more flexible, at the cost of per-resource 
audience restriction.

Does this make the use case clearer?
If you think an existing mechanism already covers it, I would appreciate a 
pointer.

Best regards,
Su-hyeon

-----Original Message-----
From: "Warren Parad"<[email protected]>
To: "이수현"<[email protected]>;
Cc: <[email protected]>;
Sent: 2026-09-28 (월) 19:00:47 (GMT+09:00)
Subject: Re: [OAUTH-WG] New draft: Presenting Issuer-Signed JWT Credentials to 
Resource Servers with DPoP

I'm pretty confused by this. I don't really understand what defines or the 
specific use case that is different from the existing mechanisms.

I think the most poignant question for me would be related to this statement in 
the draft:
 The gap is most visible for AI agents.

What gap?

On Mon, Sep 28, 2026 at 11:31 AM 이수현 <[email protected]> wrote:

Hi all,

I have posted a new individual draft:
https://datatracker.ietf.org/doc/draft-lee-oauth-dpop-credential-presentation/

It lets a client present an issuer-signed JWT credential directly to a resource 
server using DPoP (RFC 9449), with no authorization server or OpenID4VP flow in 
between.
The wire format is that of a DPoP-bound access token; the draft adds only three 
rules: the issuer is an AS or IdP the resource server already trusts, the 
credential may carry no issuer-set audience, and the resource server checks its 
status.

The motivation is clients that can simply submit a credential, such as AI 
agents calling MCP or A2A endpoints, for which OpenID4VP is more than needed.
It follows the pattern of draft-ietf-oauth-attestation-based-client-auth, but 
for the holder's credential rather than client authentication.

Comments are very welcome.

Best regards,
Su-hyeon Forten Lee



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