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Bilateral Attestation of Cross-Organization Agent Actions
draft-mih-agent-bilateral-attestation-01

Document Type Active Internet-Draft (individual)
Author Steven Mih
Last updated 2026-07-19
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draft-mih-agent-bilateral-attestation-01
Network Working Group                                             S. Mih
Internet-Draft                                  Action State Group, Inc.
Intended status: Informational                              19 July 2026
Expires: 20 January 2027

       Bilateral Attestation of Cross-Organization Agent Actions
                draft-mih-agent-bilateral-attestation-01

Abstract

   When an agent operated by one organization requests a consequential
   action from an agent operated by another, today's record of that
   exchange — if one exists — is kept by one side, editable by that
   side, and deniable by the other.  Disputes reduce to my-log-versus-
   your-log.  This document describes a bilateral attestation exchange
   for such actions: the requesting organization signs a request
   attestation binding it to the action and its material terms; the
   performing organization evaluates the request against deterministic
   constraints at the boundary where the action takes effect and signs
   an action attestation recording the constraint results and the
   disposition — performed, declined, or escalated to a human — by
   reference to the request; and each party acknowledges the other's
   attestation.  The combined record binds each organization to its
   part, gives each proof of the other's, and can be anchored to a
   transparency service so that a third party who trusts neither
   organization can verify the record end-to-end.  The exchange records
   refusals with the same fidelity as performance, and degrades
   gracefully when a counterparty cannot attest, marking the record's
   reduced assurance rather than blocking the transaction.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 20 January 2027.

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Copyright Notice

   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Motivating Scenarios  . . . . . . . . . . . . . . . . . . . .   3
   3.  Conventions and Definitions . . . . . . . . . . . . . . . . .   4
   4.  The Bilateral Exchange  . . . . . . . . . . . . . . . . . . .   5
   5.  Constraint Records  . . . . . . . . . . . . . . . . . . . . .   6
   6.  Refusal Across the Boundary . . . . . . . . . . . . . . . . .   7
   7.  Graceful Degradation  . . . . . . . . . . . . . . . . . . . .   8
   8.  Dispositions Across the Asymmetry . . . . . . . . . . . . . .   8
   9.  The Optional Relay  . . . . . . . . . . . . . . . . . . . . .   9
   10. Relationship to Existing Work . . . . . . . . . . . . . . . .   9
   11. Security Considerations . . . . . . . . . . . . . . . . . . .  10
     11.1.  Identity Is the Floor  . . . . . . . . . . . . . . . . .  11
     11.2.  Half-Completed Exchanges . . . . . . . . . . . . . . . .  11
     11.3.  Downgrade Attacks  . . . . . . . . . . . . . . . . . . .  11
     11.4.  Replay and Cross-Binding . . . . . . . . . . . . . . . .  11
     11.5.  Key Establishment  . . . . . . . . . . . . . . . . . . .  12
     11.6.  Key Compromise and Revocation  . . . . . . . . . . . . .  12
     11.7.  Canonicalization and Hash Agility  . . . . . . . . . . .  12
     11.8.  Verification-Cost DoS  . . . . . . . . . . . . . . . . .  12
   12. Privacy Considerations  . . . . . . . . . . . . . . . . . . .  13
   13. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  13
   14. References  . . . . . . . . . . . . . . . . . . . . . . . . .  13
     14.1.  Normative References . . . . . . . . . . . . . . . . . .  13
     14.2.  Informative References . . . . . . . . . . . . . . . . .  14
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .  15
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .  16

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1.  Introduction

   Agents increasingly transact with agents of other organizations with
   no human present at the moment of delegation.  The transports are
   standardized — RPC conventions, tool-call protocols, message queues —
   but transports answer _how_ agents communicate, not _who is
   accountable_ for what was requested and what was done.  Each side
   keeps its own log, written by an interested party, alterable by that
   party, and carrying no assent from the other.  When the payment posts
   twice, when the deletion was out of scope, when the delivery never
   happened, the evidence is two self-interested logs that need not
   agree.

   Classical signed B2B messaging — AS2/EDIINT signed MDNs, AS4/ebMS3
   signed receipts with non-repudiation-of-receipt — binds parties to
   _transmissions_: it attests that a message was sent and received, not
   what an agent then _did_ about it.  Such schemes do not gate
   execution on verifying the requester's organizational identity at the
   boundary where the action takes effect, do not bind constraint
   evaluation into the performer's record, and do not record a
   disposition distinguishing an executed action from a refusal from a
   human escalation at the moment of action.  The distinction this
   document draws is action-level, not transport-level.

   This document describes an exchange producing a *bilaterally attested
   action record*: each organization's signature over its part of the
   exchange is durable, independently verifiable evidence that it
   produced that part, each holds proof of the other's, and the combined
   record can be anchored so third parties can verify it.  It is an
   individual submission.  It composes with the existing agent action
   record layer [I-D.mih-scitt-agent-action-capsule] rather than
   defining a new one, and its records are designed to be consumable by
   the layers above the record — accountability composition
   [I-D.mih-sato-agent-accountability-composition] and reputation
   [I-D.mih-agent-reputation-predicates].

2.  Motivating Scenarios

   *Cross-organization procurement.* Org A's purchasing agent requests a
   fulfillment action from org B's agent.  A's request attestation binds
   A to the order's material terms; B's action attestation binds B to
   what it did about them.  A later assertion of different terms by
   either party can be checked against a record both parties signed,
   rather than argued over two private ones.

   *Agent-to-agent service delegation.* An orchestrating agent
   subcontracts a task across a trust boundary.  Each hop produces its
   own bilateral record, so a failure in a multi-hop chain is

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   attributable to the hop where it occurred rather than to the chain as
   a whole.  Chain-linking semantics that make the full responsibility
   path independently reconstructable are left to a future revision.

   *Refusal at the boundary.* B's agent declines A's request as out of
   policy.  B's action attestation records the decline and its
   constraint basis; A's acknowledgment is verifiable evidence
   contradicting a later claim by A that the request was never answered.
   The refusal becomes durable, third-party-verifiable evidence — for B,
   that its gate worked; for A, that the request was made and declined
   (see Section 6).

   *Feeding reputation.* Every completed handshake yields a
   counterparty-attested record — the highest-assurance evidence class a
   reputation predicate can consume
   [I-D.mih-agent-reputation-predicates].  Two organizations that
   transact build verifiable shared history as a side effect of
   transacting.

3.  Conventions and Definitions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   Requesting party:  The organization (via its agent) requesting a
      consequential action across an organizational boundary.

   Performing party:  The organization (via its agent) that evaluates
      and disposes of the requested action.

   Request attestation:  A signed statement by the requesting party
      describing the requested action and its material terms, bound to
      the requesting party's verifiable organizational identity and
      naming the intended performing party; including at minimum a
      content digest of the request, a nonce, a timestamp, and a
      validity window.  A request attestation is valid only against the
      performing party it names, and only within its validity window
      (with an implementation-defined clock-skew tolerance the verifier
      applies).

   Action attestation:  A signed statement by the performing party,
      referencing a request attestation by digest, recording the
      deterministic constraint results evaluated at the effect boundary
      — each constraint identified by reference so a third party can
      tell which check produced which result, pinned to a digest of the

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      constraint-set snapshot in effect and carrying a result for every
      constraint in that set (Section 5) — and the disposition of the
      request, bound to the performing party's verifiable organizational
      identity.

   Acknowledgment:  A signed statement by which a party records receipt
      of the counterparty's attestation, completing the bilateral
      record.  Receipt does not assert agreement with the attestation's
      contents; a party disputing a disposition does so in a subsequent
      linked record.

   Party identifier:  An opaque string naming a party (requesting or
      performing) within an attestation.  A party identifier MAY resolve
      to a registration entry admitted on the same transparency service
      (for example, one admitted under
      [I-D.morrison-solo-agent-earn-registration]), in which case the
      party is a registered principal with an admission record rather
      than a bare key.  Where it does, the attestation carries the
      digest of the admitted Signed Statement as the reference.

   Verifiable organizational identity:  An organizational identity a
      relying party can validate independently of that organization's
      infrastructure — a credential chaining to a root of trust the
      relying party accepts (a certificate authority, federation
      operator, registry, or published trust list).  This document does
      not nominate roots.

   Reduced-assurance indicator:  A marker recording that a given
      exchange completed with fewer than the full set of attestations
      (see Section 7).

4.  The Bilateral Exchange

   The exchange has four moves:

   1.  *Request attestation.* Before the performing party acts, the
       requesting party produces a request attestation over the action
       and its material terms.  The requester is now bound: it cannot
       later deny having asked, or having asked on these terms.

   2.  *Constraint evaluation.* The performing party verifies the
       requester's organizational identity and evaluates the request
       against deterministic constraints _at the boundary where the
       action would take effect_ — not at the transport edge.
       Verification gates execution: no verified request attestation, no
       consequential action (policy MAY permit degraded operation; see
       Section 7).

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   3.  *Action attestation.* The performing party produces an action
       attestation referencing the request attestation by digest and
       recording the constraint results and the disposition.
       Dispositions use the verdict-complete vocabulary of
       [I-D.mih-scitt-agent-action-capsule] verbatim — _executed,
       blocked, denied, timeout, errored, deferred, expired, escalated_
       — so the record covers every outcome, not only success.  A
       performing party MUST produce at most one action attestation per
       request attestation; repeated execution of a single request is
       representable only as distinct request instances, each with its
       own request attestation.

   4.  *Acknowledgment.* Each party acknowledges the other's
       attestation.  On completion, each organization is bound to its
       part and holds proof of the other's.

   Attestations and acknowledgments SHOULD be anchored: registered to a
   transparency service per [RFC9943] — carried, for example, as the
   payload of a profiled Signed Statement per
   [I-D.mih-scitt-agent-action-capsule] — so that inclusion and non-
   equivocation are verifiable by a party who trusts neither
   organization.  An unanchored bilateral record still binds the two
   parties to each other; anchoring is what makes it evidence for
   everyone else.

   Wire encodings for the four objects are TBD for a future revision;
   this document fixes the exchange, the binding obligations, and the
   disposition semantics.  A future revision fixing wire encodings MUST
   specify JCS ([RFC8785]) as the deterministic canonicalization for
   attested objects and carry an explicit hash-algorithm identifier for
   hash agility (see Section 11.7).

5.  Constraint Records

   The evidentiary value of an action attestation rests on _which_
   deterministic checks were applied and _what each returned_. Three
   obligations make that record complete and tamper-evident.

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   *Constraint-set pinning.* The action attestation MUST bind a content
   digest of the constraint-set snapshot in effect at evaluation time,
   alongside the per-constraint results.  The digest fixes _which_
   constraints — their identities and parameters — were in force when
   the request was disposed, so that a verifier can establish the
   applicable constraint set as of the attestation's anchored time, not
   merely at verification time — the same establishable-as-of-anchored-
   time property that Section 11.6 requires of key validity.  A
   constraint set that can be silently re-parameterized after the fact
   would let a performing party restate what it was obligated to check;
   pinning its digest removes that degree of freedom.

   *Input-commitment digest.* For each evaluation, the performing party
   SHOULD bind an input-commitment digest — a digest over the inputs the
   constraints consulted — anchored as a commitment and disclosable to
   the counterparty or an auditor under the selective-disclosure model
   (Section 12).  This is a SHOULD, not a MUST: the state a constraint
   consults varies across deployments, and an honest SHOULD serves a
   verifier better than a nominal MUST that implementations cannot
   uniformly satisfy.  A future revision MAY promote it on
   implementation experience.

   *Completeness.* The action attestation MUST carry a result for every
   constraint in the pinned set — each *pass*, *fail*, or *not-
   evaluated* (with a reason) — so that a constraint present in the
   pinned set but absent from the results is a _verifiable omission_
   rather than a silent gap.  Selective reporting of only the favorable
   results is thereby detectable by any party holding the pinned
   constraint-set digest.

6.  Refusal Across the Boundary

   A declined request is not a failed exchange; it is a completed
   exchange with a decline disposition.  The action attestation records
   _that_ the request was declined and _on what constraint basis_; the
   requester's acknowledgment completes the record.  This has two
   consequences.

   For the performing party, a bilaterally-acknowledged decline is
   evidence, verifiable by an auditor who trusts neither party, that its
   boundary enforcement works — the strongest form of the refusal-as-
   positive-signal reputation input described in
   [I-D.mih-agent-reputation-predicates], because here even the
   _counterparty that was refused_ has signed the record.

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   For the requesting party, a history of acknowledged declines is
   legible too: a pattern of out-of-policy requests is now provable by
   its counterparties.  Bilateral records cut both ways by construction;
   parties should expect their requesting behavior, not only their
   performing behavior, to become reputation-bearing.

7.  Graceful Degradation

   Counterparties will be of mixed capability for years.  A performing
   party whose counterpart cannot produce request attestations MAY
   proceed under policy, producing its own action attestation
   unilaterally and recording a reduced-assurance indicator in place of
   the missing attestations.  The record format is the same; the
   assurance marking differs.  This keeps one protocol across mixed
   peers while preserving the distinction relying parties need: a fully-
   bilateral record and a degraded record are never confusable, and
   consumers such as reputation predicates can require a minimum
   assurance (cf. the assurance ordering in
   [I-D.mih-agent-reputation-predicates]).  Degradation MUST be
   recorded, never silent.

8.  Dispositions Across the Asymmetry

   The action dispositions above record what the performing party
   decided about the _action_. A second, smaller class records what
   happened to the _exchange_ when it does not complete symmetrically;
   this class is meaningful only because the record is bilateral.  Three
   asymmetry dispositions are defined, entered through the schema-
   extension protocol of [I-D.mih-scitt-agent-action-capsule] and kept
   distinct from the action vocabulary:

   *  *delivery_unconfirmed:* the requesting party emitted its
      attestation but delivery to the performing party could not be
      confirmed — the weakest outcome, as the counterparty may never
      have received the request.

   *  *counterparty_timeout:* delivery was confirmed, but the performing
      party did not countersign within the request's validity window;
      the request lapses into this disposition when the window closes.

   *  *countersign_refused:* the performing party was reached and
      explicitly refused to countersign.

   These are weaker than, and MUST NOT be conflated with, a declined
   action (Section 6): a decline is a _performed_ boundary decision that
   the requester acknowledges — strong evidence — whereas a refusal to
   _countersign_ is a failure of the exchange, not a decision about the
   action.  For the same reason, a party that _declines to engage_

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   before any request obligates it is not a party that _fails to
   countersign_ a request already made; only the latter is evidentiary
   against the performing party.

   An asymmetry disposition binds to its request by correlation
   identifier and the shared action digest; a half that cannot be
   matched to a counterpart is an *orphan* — a defined state, not an
   error.  A requesting party's half, anchored (Section 9) and marked
   with an asymmetry disposition, is admissible evidence that the
   attempt was made — the one fact neither party can establish alone —
   and a verifier weights an anchored-but-unacknowledged record
   accordingly.

9.  The Optional Relay

   The exchange completes agent-to-agent; no intermediary is required,
   and the integrity of the record never depends on one.  Where the
   parties are not simultaneously reachable, a _relay_ MAY store and
   forward the attestations and issue delivery receipts.  The relay is
   an optional, substitutable role: anyone can run one, relays federate,
   and the role reads no payloads — attestations traverse it as opaque,
   integrity-protected blobs, so a relay learns that a record moved, not
   what it said.  A delivery receipt is itself an accountability claim,
   so a conformant relay MUST anchor the digests of the receipts it
   issues to a transparency log it advertises in discoverable metadata,
   where witnesses detect equivocation ([RFC9943], [RFC9942]); the log
   is the relay's choice, this document names none, and a relay that
   will not anchor its own receipts is non-conformant.  A receiving gate
   SHOULD countersign the envelope receipt, so that delivery becomes a
   fact both parties assert rather than one the relay asserts alone.
   Signed delivery receipts, and the fabrication attacks against them,
   are long-settled ground — the email DSN and MDN mechanisms
   ([RFC3461], [RFC8098]) addressed both decades ago — and this role
   inherits that discipline rather than reopening it.  Reconciliation,
   directory, retry, and admission control are deployment concerns
   outside this document's scope.

10.  Relationship to Existing Work

   *Record layer.* This document defines an exchange, not a record
   format: its attestations are designed to be carried in existing agent
   action records — the Agent Action Capsule
   [I-D.mih-scitt-agent-action-capsule] supplies the disposition
   vocabulary, effect binding, and anchoring path this document relies
   on, and its selective-disclosure profile
   [I-D.mih-scitt-agent-action-capsule-sel-disc] applies to cross-
   boundary privacy (Section 12).

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   *Delegation receipts.* [I-D.nelson-agent-delegation-receipts] binds a
   _principal_ (the delegating user) to an authorization before any
   action, on one side of the boundary.  This document binds two
   _organizations_ to a specific action at the moment of action.  The
   two compose: a request attestation may reference the delegation
   receipt authorizing the requesting agent.

   *Remote attestation.* RATS [RFC9334] attests platform and workload
   _state_ — what software is running where.  This document attests
   _actions_ — what was requested and what was done.  A deployment may
   use RATS evidence to strengthen confidence in a counterparty's agent
   runtime; the two are orthogonal layers.

   *Audit and approval records.* The audit architecture
   [I-D.kuehlewind-audit-architecture] describes recording agent
   interactions across parties, and
   [I-D.schrock-ep-authorization-receipts] records human authorization
   of high-risk actions; both are complementary record sources this
   exchange can feed and reference.  The accountability composition
   [I-D.mih-sato-agent-accountability-composition] describes how such
   records compose by shared action digest; a bilateral record naturally
   fills its cross-party leg.

   Agent Transfer Protocol (AGTP) [I-D.hood-independent-agtp] defines
   attestation within a dedicated transport, via a CONFIRM method
   producing a signed acknowledgment of a prior action and an
   Attribution-Record header for audit.  The bilateral attestation
   specified here differs in three respects: it is transport-agnostic (a
   SCITT Signed Statement that verifies identically over HTTP, A2A, MCP,
   or AGTP); it is bilateral in the strict sense — each party holds the
   other's signed attestation over the same action digest, rather than a
   one-sided acknowledgment; and each record anchors to a transparency
   service, so a party trusting neither agent can verify existence and
   non-equivocation.  The two compose: an AGTP CONFIRM MAY carry and
   anchor a capsule.

   [I-D.rampalli-scitt-capsule-provenance-binding] binds delegation-
   authorization references into the capsule payload as namespaced
   extensions, complementing both this profile and the base Agent Action
   Capsule profile by shared action digest.

11.  Security Considerations

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11.1.  Identity Is the Floor

   The evidentiary weight of a bilateral record is bounded by the
   binding of keys to organizations.  This document inherits, and does
   not solve, the organizational-identity problem; it requires only that
   the credential chain to a root the relying party accepts, and that
   identity be bound to the _record_, not merely the transport session.

11.2.  Half-Completed Exchanges

   A party that aborts mid-exchange (requests, then never acknowledges
   the decline; performs, then withholds the action attestation) creates
   an asymmetric record.  Timeout dispositions and anchoring deadlines
   bound the asymmetry: an unacknowledged attestation anchored with a
   timeout marking is itself evidence of the counterparty's non-
   completion.  Policies SHOULD treat chronic non-completion as
   reputation-bearing.

11.3.  Downgrade Attacks

   If degraded operation is permitted, an attacker prefers to be
   recorded at reduced assurance.  Reduced-assurance records MUST be
   unambiguously marked, acceptance of degraded exchanges is a policy
   decision of the performing party, and consumers SHOULD weight
   degraded records accordingly.  Silent downgrade is the failure mode
   to design out.  A performing party MUST NOT accept an exchange at
   reduced assurance without explicit policy authorization to do so;
   policy MUST be configured, never inferred from the absence of a
   request attestation.

11.4.  Replay and Cross-Binding

   Nonces and digests bind each attestation to one request instance; an
   action attestation MUST NOT be verifiable against any request other
   than the one it references.  Specifically: if a request attestation's
   requester_org or action_digest differs from the performing party's
   record at the time it evaluates constraints, the performing party
   MUST reject the exchange and produce a denied attestation, not a
   reduced- assurance indicator.  The distinction matters: reduced
   assurance records a capability gap; denial records a protocol
   violation.  Two independent verifiers deriving disposition from the
   same canonical bytes MUST reach the same verdict.

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11.5.  Key Establishment

   This document does not specify how parties establish mutual trust in
   each other's organizational keys.  First-use acceptance (TOFU) is a
   documented-risk convenience — it does not establish verifiable
   organizational identity and MUST NOT be treated as conformant with
   the identity requirements of this document.  Conformant deployments
   bind signing keys to organizational identity via a credential
   chaining to a root the relying party accepts, independent of the
   communicating parties' infrastructure.

11.6.  Key Compromise and Revocation

   A signature valid at attestation time may be produced under a key
   compromised by verification time.  A verifier SHOULD be able to
   establish key validity _as of the attestation's anchored time_, not
   only at verification time; revocation and rotation semantics for
   organizational keys are inherited from the identity layer and are out
   of scope here, but a record without an anchored time cannot support
   this distinction.

11.7.  Canonicalization and Hash Agility

   Because every binding is by digest, the canonicalization of the
   attested objects is security-relevant: divergent serializations of
   the "same" terms produce different digests, and ambiguous
   canonicalization enables terms-substitution disputes.  A future
   revision fixing wire encodings MUST specify JCS ([RFC8785]) as the
   deterministic canonicalization and carry an explicit hash-algorithm
   identifier for agility.  Until wire encodings are fixed,
   implementations SHOULD document the canonicalization they apply and
   treat any divergence from a counterparty as a protocol error.

11.8.  Verification-Cost DoS

   Verifying a request attestation (identity-chain plus anchor
   inclusion) is more expensive than producing one.  A performing party
   SHOULD be able to cheaply reject unverifiable request attestations
   before performing full verification, so request-attestation flooding
   cannot exhaust a performer at the effect boundary.

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12.  Privacy Considerations

   A bilateral record discloses, by construction, that two organizations
   transacted — to each other, and if anchored with cleartext
   identifiers, to anyone.  Deployments SHOULD anchor commitments rather
   than cleartext (selective-disclosure structures per
   [I-D.mih-scitt-agent-action-capsule-sel-disc]), disclose material
   terms only to the counterparty and auditors, and treat counterparty
   identity itself as a selectively-disclosable field where the use case
   allows.  Correlation of anchored records across a party's exchanges
   (client-list reconstruction) is the residual risk; mitigations are
   TBD alongside the reputation layer's, which faces the same problem
   from the consumption side.

13.  IANA Considerations

   This document has no IANA actions at this time.  A future revision
   defining wire encodings is expected to register media types for the
   four exchange objects and a registry for reduced-assurance indicator
   values.  TBD.

14.  References

14.1.  Normative References

   [RFC9942]  Steele, O., Birkholz, H., Delignat-Lavaud, A., and C.
              Fournet, "CBOR Object Signing and Encryption (COSE)
              Receipts", RFC 9942, DOI 10.17487/RFC9942, June 2026,
              <https://www.rfc-editor.org/rfc/rfc9942>.

   [RFC9943]  Birkholz, H., Delignat-Lavaud, A., Fournet, C., Deshpande,
              Y., and S. Lasker, "An Architecture for Trustworthy and
              Transparent Digital Supply Chains", RFC 9943,
              DOI 10.17487/RFC9943, June 2026,
              <https://www.rfc-editor.org/rfc/rfc9943>.

   [RFC8785]  Rundgren, A., Jordan, B., and S. Erdtman, "JSON
              Canonicalization Scheme (JCS)", RFC 8785,
              DOI 10.17487/RFC8785, June 2020,
              <https://www.rfc-editor.org/rfc/rfc8785>.

   [I-D.mih-scitt-agent-action-capsule]
              Mih, S., "An Agent Action Capsule Profile for SCITT", Work
              in Progress, Internet-Draft, draft-mih-scitt-agent-action-
              capsule-02, 6 July 2026,
              <https://datatracker.ietf.org/doc/html/draft-mih-scitt-
              agent-action-capsule-02>.

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   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/rfc/rfc2119>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.

14.2.  Informative References

   [RFC3461]  Moore, K., "Simple Mail Transfer Protocol (SMTP) Service
              Extension for Delivery Status Notifications (DSNs)",
              RFC 3461, DOI 10.17487/RFC3461, January 2003,
              <https://www.rfc-editor.org/rfc/rfc3461>.

   [RFC8098]  Hansen, T., Ed. and A. Melnikov, Ed., "Message Disposition
              Notification", STD 85, RFC 8098, DOI 10.17487/RFC8098,
              February 2017, <https://www.rfc-editor.org/rfc/rfc8098>.

   [I-D.mih-agent-reputation-predicates]
              Mih, S., "Agent Reputation Predicates for SCITT-Anchored
              Action Records", Work in Progress, Internet-Draft, I-
              D.mih-agent-reputation-predicates-00, July 2026,
              <https://datatracker.ietf.org/doc/html/I-D.mih-agent-
              reputation-predicates-00>.

   [I-D.mih-sato-agent-accountability-composition]
              Mih, S., Sato, Bu, S., and I. Schrock, "Agent
              Accountability: Composition and Conformance", Work in
              Progress, Internet-Draft, draft-mih-sato-agent-
              accountability-composition-00, 5 July 2026,
              <https://datatracker.ietf.org/doc/html/draft-mih-sato-
              agent-accountability-composition-00>.

   [I-D.mih-scitt-agent-action-capsule-sel-disc]
              Mih, S., "Selective Disclosure Profile for Agent Action
              Capsules", Work in Progress, Internet-Draft, draft-mih-
              scitt-agent-action-capsule-sel-disc-00, 19 June 2026,
              <https://datatracker.ietf.org/doc/html/draft-mih-scitt-
              agent-action-capsule-sel-disc-00>.

   [I-D.nelson-agent-delegation-receipts]
              Nelson, R., "Delegation Receipt Protocol for AI Agent
              Authorization", Work in Progress, Internet-Draft, draft-
              nelson-agent-delegation-receipts-10, 13 June 2026,
              <https://datatracker.ietf.org/doc/html/draft-nelson-agent-
              delegation-receipts-10>.

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   [I-D.kuehlewind-audit-architecture]
              Kühlewind, M. and H. Birkholz, "An Architecture for
              Auditing AI Agent Delegation and Interactions", Work in
              Progress, Internet-Draft, draft-kuehlewind-audit-
              architecture-00, 18 May 2026,
              <https://datatracker.ietf.org/doc/html/draft-kuehlewind-
              audit-architecture-00>.

   [I-D.schrock-ep-authorization-receipts]
              Schrock, I., "Authorization Receipts for High-Risk Agent
              Actions", Work in Progress, Internet-Draft, draft-schrock-
              ep-authorization-receipts-07, 19 July 2026,
              <https://datatracker.ietf.org/doc/html/draft-schrock-ep-
              authorization-receipts-07>.

   [RFC9334]  Birkholz, H., Thaler, D., Richardson, M., Smith, N., and
              W. Pan, "Remote ATtestation procedureS (RATS)
              Architecture", RFC 9334, DOI 10.17487/RFC9334, January
              2023, <https://www.rfc-editor.org/rfc/rfc9334>.

   [I-D.hood-independent-agtp]
              Hood, C., "Agent Transfer Protocol", Work in Progress,
              Internet-Draft, draft-hood-independent-agtp, n.d.,
              <https://datatracker.ietf.org/doc/html/draft-hood-
              independent-agtp>.

   [I-D.rampalli-scitt-capsule-provenance-binding]
              Rampalli, K., "SCITT Capsule Provenance Binding", Work in
              Progress, Internet-Draft, draft-rampalli-scitt-capsule-
              provenance-binding, n.d.,
              <https://datatracker.ietf.org/doc/html/draft-rampalli-
              scitt-capsule-provenance-binding>.

   [I-D.morrison-solo-agent-earn-registration]
              Morrison, B., "Agent Earn Registration", Work in Progress,
              Internet-Draft, draft-morrison-solo-agent-earn-
              registration, n.d.,
              <https://datatracker.ietf.org/doc/html/draft-morrison-
              solo-agent-earn-registration>.

Acknowledgments

   This exchange pattern owes its framing to discussions in the SCITT
   and agent-accountability communities, and composes with the work of
   the authors cited above.

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   Iman Schrock (EMILIA Protocol) contributed the constraint-record
   obligations in this revision: constraint-set pinning (MUST), input-
   commitment digest (SHOULD), and completeness (MUST).

   Blake Morrison contributed the party-identifier MAY sentence in the
   Conventions and Definitions section, enabling party identifiers to
   resolve to registration entries admitted on the same transparency
   service.

Author's Address

   Steven Mih
   Action State Group, Inc.
   Email: spec@actionstate.ai

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