[WIMSE] Re: New I-D: draft-thaha-wimse-agent-evidence-binding-00 (evidence binding for AIMS audit)

[Shameer Thaha <[e-mail]>]

Mikhail, Kieran,

Thank you, both points are right.

The sentence stating that a Serving Party cannot refuse a call because a
prior actor is suspended is too broad, appearing in both the Introduction
and the Confused Deputy entry of the SCITT draft. RFC 8693 Section 4.1
rules out using the nested act claims for that decision. It does not rule
out checking separately verified delegation tokens under a delegation-chain
profile. We will use Mikhail's wording in both places: "cannot refuse a
call on the basis of the nested act claims because a prior actor has since
been suspended".

We will also replace "neither complete nor evidence that any hop held or
narrowed authority" with "does not by itself establish that it is complete,
or that any hop held or narrowed authority". That sentence is in the SCITT
draft's Admission section and in step 4 of the Evidence Binding draft, so
we will change both.

These changes will go into the next revision of each draft.

Best regards,
Shameer

On Thu, Nov 12, 2026 08:17 AM, Mikhail Sergeev <[e-mail]>
wrote:

> Kieran, Shameer, Shaibi,
>
> Thanks, Kieran. Direction (a) is already in the posted texts: SCITT -02
> Section 6.7.2, and Evidence Binding -02/-03 Section 5 step 4 and Section
> 6.2.
>
> One point remains in SCITT -02. Section 1 and the "Confused deputy" entry
> in Section 11 say that a Serving Party cannot refuse a call because a prior
> actor has been suspended. RFC 8693 Section 4.1 limits the token consumer to
> the token's top-level claims and current actor; prior actors in nested act
> claims are informational only. Separately verified delegation tokens
> provide a different basis for checking authority and revocation under the
> applicable delegation-chain profile: a chain in the
> draft-asor-wimse-agent-delegation-chain-03 format is verified hop by hop,
> and where its tokens carry status references, step 7 denies when an
> accepted status answer marks any token in the chain revoked, within the
> status list's freshness window. Suggested wording for both places: "cannot
> refuse a call on the basis of the nested act claims because a prior actor
> has since been suspended".
>
> A smaller one: "neither complete nor evidence" reads as saying the history
> is incomplete. "does not by itself establish that it is complete, or that
> any hop held or narrowed authority" says what is meant.
>
> Mikhail
>
> On Wed, Nov 11, 2026 07:15 PM, Kieran Sweeney <[e-mail]> wrote:
>
>> Mikhail,
>>
>> You are right, and thanks for checking it against the RFC. My "policy
>> input" line was wrong: Section 4.1 keeps prior actors out of the
>> access-control decision, so deny-listing one still conflicts with it.
>> Direction (a) is the correct reading, and Shameer and Shaibi have said they
>> will take it in -02. The rest of what I said stands: act is attribution,
>> and per-hop authority needs separately verified evidence.
>>
>> Kieran
>>
>>