]> Action State Group, Inc.

steven@actionstate.ai

MyAuberge K.K.

Japan tomsato@myauberge.jp

EMILIA Protocol, Inc.

team@emiliaprotocol.ai

Independent

bluedognull@gmail.com

Tyche Institute

anton.sokolov@tyche.institute

Security agent accountability audit SCITT composition conformance attestation Autonomous and semi-autonomous software agents increasingly take consequential actions across administrative and trust domains. Holding such an action accountable — to a regulator, auditor, or counterparty who does not trust the operator — requires answering several questions, each answerable by an independently-verifiable profile: whether the agent was permitted to act (CAN), which accountable human authorized the specific action (WHO), what outcome the agent system recorded and what is known to have crossed the effect boundary (WHAT), and whether the runtime enforced correctly (AUDIT). This document specifies, in Informational terms, how such profiles compose — by a shared action-digest, each verifying independently — and defines a shared conformance-vector suite against which any profile may be tested. It complements existing audit-architecture and record-format work rather than replacing it, reusing existing signing, transport, and transparency mechanisms. Its focus is an assurance tier those documents leave open: most agent records today are self-attested by an interested party; this document makes reachable and testable an anchored, third-party-verifiable tier, in which a record is registered to a transparency service (SCITT) so a party who trusts neither the agent nor the operator can verify it. Self-attestation remains a valid baseline; convergence on the disinterested tier — by any conforming profile — is the goal, not a single mandated format.

Introduction Autonomous agents are non-deterministic, act without per-step human oversight, cross administrative and trust boundaries, and delegate to other agents. The assumptions that let earlier systems be trusted — predictability, runtime supervision, a nameable human in the loop — do not hold by default. When behaviour cannot be supervised as it happens, trust must relocate to evidence that can be checked afterward and, because agents act across organizational boundaries, checked without trusting the operator. Identity and authorization are necessary but not sufficient: they establish which agent and what it was permitted to do, but the risks that characterize agent systems — goal drift, prompt injection, fabricated tool results, action outside scope — occur in the gap between what was authorized and what was actually done. Holding a consequential agent action accountable therefore requires answering several questions, each answerable by an independently-verifiable profile: whether the agent was permitted to act (CAN), which accountable human authorized the specific action (WHO), what outcome the agent system recorded, and what is known to have crossed the effect boundary (WHAT), and whether the runtime enforced correctly (AUDIT). This document does not define a new audit architecture; it complements the existing architecture and record-format work in this space (see Relationship to Existing Work) and specifies the piece they leave open: how profiles answering these questions compose, by a shared action-digest, into one record, and how conformance — both to that composition and to an anchored, third-party-verifiable assurance tier — is tested. Two principles frame it: (1) composition by shared digest, not containment — each profile verifies independently and refers to the same action by a shared digest; and (2) producer-agnostic neutrality — no profile is a required root of trust for another. The set of questions is open and extensible (agent identity and belief-provenance are natural further slots), and the composed evidence serves both after-the-fact accountability and the forward-looking authorization and trust decisions that rely on it.

Terminology 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 when, and only when, they appear in all capitals, as shown here. Slot: one of the interchangeable questions (CAN, WHO, WHAT, AUDIT, and any later extension) that a conforming profile answers about an action (see Overview: Questions and Composition). Profile: a concrete, independently verifiable specification that fills one slot. Any conforming profile may fill a slot; the profiles cited in this document are the first instances, not the definition of the slot. Composition vector: the shared positive test vector — one action's exact, frozen input bytes threaded through each populated slot — against which conformance is tested (see Conformance). Profile-tagged authority-reference digest: a digest, tagged with its owning profile's label, that commits to the native evidence object or statement supporting a slot's assertion (see Three Digest Roles). Trust root: the entity or key material a verifier is configured to accept as the anchor for validating a profile's evidence. Composition is by shared digest, not containment: no profile is a required trust root for another.

Problem Statement and Regulatory Mapping An agent acts across a trust boundary. Some time later, someone who trusts neither the agent nor its operator needs to answer a simple question: was this action authorized, and can that be shown without taking the operator's word for it. Knowing who an agent is, and confirming it had permission to act, does not establish what outcome the agent system recorded or whether a claimed effect crossed the effect boundary. Identity answers who and authorization answers may; neither supplies the recorded outcome or independent evidence of an external effect. This has stopped being a someday problem. Under the AI Omnibus amendment, the EU AI Act's Article 12 record-keeping and automatic-logging obligations for high-risk systems apply from December 2, 2027, and the rules governing AI embedded in regulated products apply from August 2, 2028. NIST's AI Agent Standards Initiative and Singapore's IMDA agentic-AI guidance are moving in the same direction independently. None of these converge on a specific format — that convergence is cited here as demand, not as a compliance claim this document makes on anyone's behalf — but the direction is consistent: regulators are going to ask deployers of agentic systems to produce records an outside party can check, not records the operator merely asserts. Two of these efforts began close together but not, as sometimes stated, in the same month: Singapore's IMDA opened its agentic-AI guidance work in January 2026, and NIST's AI Agent Standards Initiative launched independently the following month, in February 2026. IMDA's guidance has since moved to version 1.5, published May 20, 2026 and updated June 5, 2026. On the EU side, the obligations described above are now enacted as Regulation (EU) 2026/1744, not merely proposed. None of these bodies coordinate on a specific record format; each independently converges on the same demand — that deployers of agentic systems produce records an outside party can check. No existing layer answers this alone, and it's worth being precise about why, since each addresses a real and different concern. Runtime monitoring detects anomalous behavior as it happens — valuable, but it produces observability data, not verifiable evidence a skeptical third party can check independently after the fact. The individual identity and attestation work underway in WIMSE, RATS, and SCITT each answers a real piece of the picture — whose workload this is, what posture a runtime attests to, how a statement gets anchored — but none of them, alone or informally combined, answers the specific question a regulator or counterparty actually asks: was this exact action authorized, by whom, and is the record of what happened tamper-evident. That composition is the gap this work fills. Four questions decompose that gap into independently answerable, independently verifiable parts: CAN — was the agent permitted to act? WHO — which accountable human authorized this exact action, as distinct from which agent carried it out? WHAT — what outcome did the agent system record, and what is known to have crossed the effect boundary — a byte-stable serialization of a producer-observed or producer-recorded action record, not a replay of the action, sufficient to judge the outcome? AUDIT — did the runtime enforce correctly, in causal order, tamper-evidently? Each question is answerable by an independently-verifiable profile, and a verifier holding only one profile can verify it without trusting any other profile's producer. This document does not define new record types to carry those answers. It composes within the existing audit architecture — and the record types it defines — rather than proposing a second architecture above it. Where the four questions as stated here and that architecture's record types conflict, the architecture governs; this section, and this draft, are written to be reconciled against it, not around it. An answer to any of these four questions is only useful to an outside party — someone who trusts neither the agent nor its operator — once it's registered: filed with a SCITT transparency service under a public policy, so anyone can independently confirm the filing happened without having to trust the agent or the operator's word for it. This matters specifically because the actors being audited are not static. Persistent memory makes agent behavior path-dependent, and agents rewrite their own scaffolding and spawn sub-agents — the system acting at step N is not necessarily the one that would be reviewed at step 0. A registered record, once anchored, stays tamper-evident and datable to its registration even as the actor that produced it changes underneath it. Self-attested records remain valid and useful as a baseline; registration is what makes the stronger claim reachable and testable, for any conforming profile, without mandating a particular format. Two limits matter here, stated plainly. First, a registered record only proves a signed claim existed at a given time — it doesn't prove the claim is true. Second, registration stops someone from tampering with a record after it's filed, but it doesn't guarantee every action that should have been recorded actually was, and it doesn't rule out a second, contradictory record existing somewhere else. Making sure nothing was left out is a separate problem — one for disclosure rules and monitoring, not something a transparency service can solve on its own, and not something claimed here. In short: this section explains why four separate questions are needed, and what registering an answer to one of them actually gives a skeptical outside verifier. How the profiles technically link together — the shared digest, how it's calculated — is resolved in the sections that follow.

Overview: Questions and Composition The work centers on a set of interchangeable slots, each a question that a conforming profile answers: CAN — the "may": was the agent permitted to act? WHO — which accountable human authorized this exact action? WHAT — what outcome did the agent system record, and what is known to have crossed the effect boundary (verdict-complete; a byte-stable serialization of the producer-recorded outcome, not a replay)? AUDIT — did the runtime enforce correctly, in causal order, tamper-evidently? Any conforming profile may fill a slot; the profiles cited in this document are the first instances, not the definition. An action fills the slots its trust requirement calls for; not every action populates every slot. The set is extensible (see Extension Points).

The Composition Model Profiles compose either by reference to a shared subject digest over the action — the join key the slots refer to — or through an explicit, cryptographically protected cross-reference. A profile-tagged authority-reference digest binds a slot's evidence to the registered object it commits to, and a receipt-payload digest binds transparency receipts. Digests committing to signed bytes require deterministic encoding. The subject-digest construction (subject_digest = HASH(subject_preimage)) is defined per profile, as set out in the following subsections; no single canonicalization is imposed.

Three Digest Roles Profiles compose either by reference to a shared subject digest over the action or through an explicit, cryptographically protected cross-reference between profile-native subject digests. A subject digest is: subject_digest = HASH(subject_preimage) where the profile defines the subject data model, the exact preimage bytes, the hash algorithm, any domain-separation bytes, and the digest representation. JCS is one possible canonicalization choice; it is not imposed on profiles that select another byte construction. The composition carries three distinct digest roles: The subject digest identifies the action or action projection to which a slot's assertion applies. A profile-tagged authority-reference digest commits to the native evidence object or statement that supports the slot assertion. A receipt-payload digest commits to the exact bytes submitted to a transparency service and covered by its receipt. These digest values MAY differ. A profile MUST state which object and exact byte sequence each digest covers, and a composition verifier MUST NOT infer equality or transitive coverage merely because two fields use the same hash algorithm. Where one signed object links the roles, the protected portion of that object MUST cover the relevant digest values and their profile labels.

Digest Context and Representation Every digest comparison requires a digest context consisting at least of the profile label and version, covered field set or projection, canonicalization profile, hash algorithm, domain-separation rule, digest encoding, and digest representation. Profile labels are protocol inputs, not display metadata. A missing, unknown, or incompatible profile label is a failed join, not permission to apply a local default. Raw digest bytes and textual encodings are different values. In particular, a 32-byte SHA-256 output, the 64 ASCII characters of its lowercase hexadecimal encoding, and the ASCII string formed by prepending sha256: to that encoding MUST NOT be substituted for one another. A profile MUST state which representation appears in each field and which representation, if any, is included in a further digest preimage. Two profiles may use digest equality as a direct join only when their complete digest contexts are compatible and the compared preimage byte sequences are demonstrated to be identical, for example by a shared frozen test vector. Otherwise, they compose through an explicit, cryptographically protected cross-reference that names both profiles and binds both digest values. A cross-reference proves the stated association; it does not make the native digest constructions identical. Digest equality is a join key: it does not, by itself, prove truth, authorization, sufficiency, completeness, or policy compliance. Native profile verification, digest recomputation, receipt or transparency verification, completeness and sequencing checks, and relying-party acceptance remain separate results.

Cross-Profile Reviews The following entries record the application of external review frameworks to the composition model's slot mappings. Each entry is contributed by the reviewing author and records only what that author's analysis found; no entry implies byte-agreement results or conformance claims not explicitly stated.

Principal-Binding Review (Bu) Principal-binding review framework (Bu): verifier-facing claim, carrier, verifier, binding, accepted-result, and failure boundaries from were used to review the WHO-slot mapping. The AAC Class-1 repository was independently replayed at commit 10342f504b051a24908053465927efdaea3ec2f6, but no independent principal-binding byte-agreement result is claimed. Status: framework mapping reviewed; AAC reference suite independently replayed. The historical review used revision -03 of . A comparison with the published -06 text confirms that the five terminology definitions cited above and the C-002 registry definition are unchanged. This does not imply that all review requirements are unchanged. Compared with -03, -06 explicitly defines six row outcomes in Section 16, adds dependency-closure rules in Section 17 and scoped human continuity as C-014, and adds claim-grounding and relying-party-decision fields. Section 26 also gives C-002-specific negative cases requiring evidence of pre-effect authorization ordering and of the binding between an attester and the named principal. The review retains its bounded WHO-attribution finding and the recorded reference-suite replay. It does not infer pre-execution authority from attribution, claim a complete evaluation against the -06 framework, or establish independent principal-binding byte agreement. A stronger mapping claim requires the additional applicable rows and evidence to be reviewed explicitly. Additional cross-profile review entries may be added in a later revision as other constituent-profile authors complete their own framework reviews.

Worked Profile Illustration On the permit side, the abstract PermitReceipt architecture () leaves canonicalization and action-digest construction to a selected profile; it does not mandate JCS or any other single canonicalization. A verifier that cannot establish canonicalization-profile compatibility is required to return DENY rather than treat digest values as comparable across an unestablished profile boundary. In the frozen CP-JSON-2 public-evaluation profile () — one evaluation profile of that architecture, not a universal construction of it — the action digest is the 64-character lowercase hexadecimal encoding of SHA-256 over the exact canonical request bytes. That profile prepends no additional domain-separation bytes to the action-digest preimage. This profile-specific construction does not imply byte identity with JCS-based profiles. For a particular test vector, digest equality across profiles may serve as a direct join for that vector only when the complete digest contexts are compatible and the compared preimage byte sequences are demonstrated to be identical. Relevant context includes the field set, digest algorithm, canonicalization profile, domain-separation rule, encoding, and digest representation. Otherwise, the profiles compose through an explicit, cryptographically protected cross-reference. In , receipt_core.action_digest is the unprefixed 64-character lowercase hexadecimal text, while authorization_ref.action_commitment is the literal ASCII prefix sha256: followed by the same 64 hexadecimal characters. Neither textual representation is the raw 32-byte digest. The digest preimage is the exact byte sequence designated by the selected profile or frozen vector. Human-readable renderings, pretty-printed documents, console output, and files containing added line terminators are not interchangeable with that preimage unless the profile explicitly designates those exact bytes. This illustration states profile-specific implementation facts. It makes no CAN slot proposal, conformance or interoperability claim, endorsement claim, production-readiness claim, joint-ownership claim, or patent or license claim. Attribution: "ORPRG profile-specific worked illustration based on and . The permit-side construction and the ORPRG-specific implementation facts concerning profile compatibility and digest representation reflected in this illustration were identified and documented in the permit-side review and were supplied and owner-confirmed by Yong Bok (Scott) Lee, Meridian Verity Group." Acknowledgment: "The cross-profile binding discussion in this section was informed by the ORPRG row of a versioned digest-binding matrix and by the subsequent multi-party composition review. The ORPRG row and its supporting permit-side observations were supplied and owner-confirmed by Yong Bok (Scott) Lee, Meridian Verity Group."

Trust-Root Separation Each slot may root in a different trust anchor (e.g. a human device key, a kernel attestation key (), a transparency-log operator). The composition holds even if any one party is compromised or under review. No slot is a required root of trust for another; profiles remain producer-agnostic.

Slot Profiles The profiles in this section are first instances filling the slots named above, recorded so the composition can be tested against something concrete. They are not the slot definitions; any conforming profile may fill a slot (see Overview). Each profile's text is contributed and maintained by its authors.

The CAN Slot

Design Rule The CAN slot asks whether a declared authority issued a bounded grant that covers the requested action at the authorization decision point, before the external effect is committed, and whether the relying party accepts that grant under its stated trust and policy inputs. It does not identify the accountable human who authorized the action (WHO), prove what action occurred (WHAT), or prove that the runtime enforced correctly (AUDIT). A CAN result also does not establish that the declared action description equals the real-world effect; that binding remains an obligation of the relying party that performs the effect. The first-instance profile is MachineMandate (): a holder-bound, short-lived authorization credential whose signed claims identify an agent subject, declare a credential type and bounded scope, and commit to a profile-defined action projection. The selected composition profile separately pins the credential format and profile version; the frozen MachineMandate vct string shown below is not itself versioned. A presentation can use SD-JWT VC () and OpenID for Verifiable Presentations (), including verifier-provided nonce and audience values. A relying party verifies the native credential and presentation, appraises the issuer under its authorization policy, recomputes the action commitment, and evaluates each declared scope dimension before returning ALLOW or DENY. MachineMandate is one CAN instance, not the CAN slot. Other authorization formats may fill the slot if they expose equivalent independently verifiable inputs and results.

Producer Requirements A conforming MachineMandate CAN producer MUST state: the credential-format profile, version, media type, and credential-type identifier; the issuer identifier, key-discovery or trust-anchor mechanism, and the profile-specific role or policy under which that issuer is authorized to grant the declared scope; the agent subject and the proof-of-possession or holder-binding mechanism; the scope fields and the semantics, units, currency, comparison rule, and default-deny behavior of every scope dimension; the action field set or projection covered by the action commitment; the exact action-commitment preimage bytes, canonicalization profile, digest algorithm, domain-separation rule, encoding, and digest representation; any authorization-relevant action dimension evaluated outside the action commitment, and the separate gate that evaluates it; the issued-at and expiry semantics, any not-before rule, and the status or revocation mechanism, if one is used; the semantics of any credential identifier or one-time-use field and the state required to enforce those semantics; the exact native authority object referenced by the composition, including its profile-tagged authority-reference digest and byte preimage; when that authority-reference preimage excludes presentation-specific material, the exact disclosures, holder-binding proof, verifier nonce, audience, and other transcript inputs needed to reproduce the native presentation appraisal, together with an integrity-protected reference to those inputs; and all issuer-role, policy, status, and trust inputs needed to reproduce the authorization appraisal, including the policy-evaluation time. A producer MUST NOT describe a credential identifier as single-use unless the selected verifier profile maintains and checks the state needed to reject a second use. It MUST NOT describe a short validity window as revocation. An absent, unknown, or incompatible profile, scope unit, trust input, or action-commitment rule is a failed CAN appraisal, not permission to apply a local default.

Verifier Requirements A conforming MachineMandate CAN verifier MUST report separately: machine_mandate_reference_bound: whether the protected composition reference identifies the expected MachineMandate artifact type, profile, digest algorithm, exact authority-reference preimage, and digest; machine_mandate_appraised: whether the native credential and presentation validate under the selected credential-format profile, including issuer signature, disclosure processing, proof of possession or holder binding, verifier nonce and audience, temporal validity, credential status when applicable, required-claim presence, and issuer-role or trust-policy checks; machine_mandate_action_hash: whether the verifier's recomputation over the declared action projection, under the exact profile and byte rules, equals the issuer-protected action commitment and, when the profile carries a set of permitted action commitments, whether that commitment is a member of the issuer-protected set; and one separately named result for every authorization-relevant scope dimension, including machine_mandate_spend when the profile declares a spending limit. The verifier MUST return DENY if any required gate fails or cannot be evaluated. It MUST NOT collapse reference binding, credential validation, issuer appraisal, action-commitment recomputation, and scope evaluation into one opaque "authorized" boolean. Each reported gate MUST distinguish at least PASS, DENY, and NOT_EVALUATED. When evaluation stops after an earlier rejection, a later gate is NOT_EVALUATED; it is not a second rejecting gate. A run record that reports a first rejecting gate MUST preserve this distinction. When SD-JWT VC and OpenID4VP are selected, the verifier MUST apply the validation rules of the pinned SD-JWT, SD-JWT VC, and OpenID4VP profiles, including strict algorithm and type checks, issuer-identifier-to-key binding, rejection of uncommitted or conflicting disclosures, required-claim validation, and key binding. The first-instance profile described here requires holder binding even though SD-JWT permits profiles in which key binding is optional. Merely decoding the JWT claims, successfully verifying one signature, or observing a known credential-type string does not establish machine_mandate_appraised. The final CAN result is:

The CAN verifier evaluates the action presented to the relying party, not a value supplied by the agent as an asserted hash. The relying party MUST reconstruct the profile-defined action projection from the request it is about to authorize, compute the commitment itself, and use the same request values for all scope gates. It MUST bind an ALLOW result to that request and MUST NOT reuse the result for a changed action. If effect commitment is delayed beyond the recorded policy-evaluation time, or if a relevant credential, status, or policy input can have changed, the relying party MUST re-evaluate before committing the effect.

Separation from WHO and AUDIT An issuer, principal, or mandate claim does not by itself answer WHO. A MachineMandate CAN profile MAY carry or selectively disclose a principal reference, but a named-human authorization claim belongs in a separately verified WHO profile unless the MachineMandate profile independently meets that profile's requirements. A principal reference a CAN record exposes at the seam follows the commitment rule of . Runtime attestation is likewise not a prerequisite for verifying the native CAN credential. The current MachineMandate research demonstrator combines credential, issuer-role, runtime-attestation, and scope gates in one end-to-end verdict. In this composition, the credential, issuer-role, action-commitment, and scope results map to CAN; RATS/TPM freshness and platform appraisal map to AUDIT. The composition MAY require both results for a relying-party decision, but a failed or absent AUDIT result MUST NOT be mislabeled as failure to parse or cryptographically verify the CAN credential.

Frozen IETF 126 Illustration NOTE: '' line wrapping per . One frozen, pre-execution MachineMandate vector uses the credential type:

Its composition reference commits to the exact 1190-byte issuer-signed JWT component of the SD-JWT presentation. That component has SHA-256:

The authority-reference field carries that digest as unprefixed lowercase hexadecimal text under an explicitly declared SHA-256 digest context. It is distinct from the prefixed textual action commitment below. Because this stable reference covers only the issuer-signed component, it does not by itself commit to the selected disclosures, Key Binding JWT, verifier nonce, or audience of a particular presentation. A record claiming machine_mandate_appraised MUST preserve and integrity-protect that separate presentation evidence. The action-commitment profile in that vector covers the 91 UTF-8 bytes of:

and carries the textual commitment:

The profile declares scope.allowed_actions, scope.action_commitments, and scope.max_spend, with spending values fixed by the vector's mapping profile to EUR minor units. The requested amount is not part of this vector's action-commitment preimage; it is evaluated independently by machine_mandate_spend. Therefore, the action commitment alone MUST NOT be described as committing to the payment amount. The combined CAN decision binds the declared action projection and separately applies the amount limit. The public MachineMandate repository contains another action profile used by the paper/demo path, where the action projection is {tool, amount_eur, to}. That digest context is not compatible with this frozen vector's {action_id, outcome} projection. A draft or test vector MUST identify which profile it uses and MUST NOT compare, substitute, or make transitive claims across the two action commitments merely because both use SHA-256 and a JSON canonicalization rule. The text eur:250:acme-corp:vienna-interop-2026-001 in the frozen vector is an opaque outcome descriptor. A verifier MUST NOT infer amount or currency semantics from that string; those semantics are supplied only by the separately declared amount, currency, unit, and mapping-profile inputs. The frozen credential was issued at 2026-07-18T13:37:15Z and expires at 2026-07-24T23:59:59Z. In its credential self-check record, the positive case requests 25000 EUR minor units and expects all MachineMandate gates to pass. The frozen over-limit case requests 75000 against scope.max_spend = 50000; it expects the reference, native appraisal, and action-commitment gates to pass, and machine_mandate_spend to be the sole rejecting MachineMandate gate. These are frozen vector expectations and credential self-check inputs, not a completed interoperability result. The frozen PermitReceipt and MachineMandate action constructions use different preimages. Their relationship is therefore an explicit protected cross-reference, not digest equality. The frozen proposed composition profile specifies a signed Agent Action Capsule payload that co-binds the typed PermitReceipt reference and the typed MachineMandate reference. This does not absorb PermitReceipt into MachineMandate, make either format the CAN slot, or cause one native appraisal to imply the other.

Composition and Transparency Seams At the composition join, a MachineMandate CAN profile exposes: its profile and credential-type identifiers; the subject digest and complete digest context for the action projection; the profile-tagged authority-reference digest for the exact native credential object; an integrity-protected reference to the exact presentation evidence when it is not included in the authority-reference preimage; the protected scope fields or their disclosure-aware commitments; the separately named native-appraisal, action-commitment, and scope-gate results; and the relying party's final CAN result and policy inputs. If a MachineMandate statement or a detached digest of it is registered with a SCITT transparency service, the SCITT receipt supplies the separate receipt-payload digest. The receipt proves registration under the service policy. It does not establish issuer authority, credential validity, action coverage, scope sufficiency, or CAN acceptance.

Negative Vectors In addition to the composition-level negative classes, a MachineMandate CAN profile MUST include vectors for at least: a protected reference to the wrong credential bytes; an unsupported or mislabeled credential profile, credential type, media type, or signature algorithm; an invalid issuer signature; a disclosure not committed by the issuer-signed SD-JWT; duplicate or conflicting disclosures for one claim name; a required claim that is missing, selectively hidden when the profile requires disclosure, or present under an unexpected type; invalid proof of possession or holder binding; a valid issuer-signed component paired with a presentation transcript, disclosure set, or Key Binding JWT different from the one appraised; a mismatched verifier nonce or audience; an expired or not-yet-valid credential; a revoked or suspended credential when the selected profile claims status enforcement; an issuer key that verifies cryptographically but is not accepted for the required authorization role; a changed action field after issuance; a canonicalization, profile-label, or digest-representation mismatch; a requested action outside allowed_actions; a missing required action commitment; an amount above max_spend; a currency or unit mismatch; a second use when the selected profile claims one-time semantics; a scope field omitted and then supplied from an undeclared local default; a later scope gate skipped after an earlier rejection but incorrectly reported as an independently evaluated DENY; and a transparency receipt bound to a different payload.

Current Assurance Boundary The public MachineMandate repository and paper are research artifacts. The current issuer key, holder key, qtsp://issuer identifier, and trust-list inputs used by the frozen composition credential are synthetic, run-specific inputs. They do not establish a real qualified trust-service provider, national trust framework, production issuer authorization, or production status service. In particular, the demonstrator's synthetic AgentRuntimeEndorser trust-list role is not evidence that the same issuer is authorized by a production ecosystem to issue machine mandates. The repository's credential code is an implementation used to exercise the construction; this text does not claim that the implementation has been tested for conformance to , , draft-ietf-oauth-sd-jwt-vc-17, or OpenID4VP. The repository describes its JSON canonicalization as an RFC 8785 subset and its credential implementation as simplified; the exact frozen bytes and profile identifiers, rather than a generic conformance assumption, control the vectors. The artifact does not implement a production revocation service or a persistent single-use replay cache. Its short validity window and credential identifier MUST NOT be promoted into either claim. At the initial 2026-07-23 hostile-review point, vocab.tyche.institute did not resolve in DNS. Later that day, Tyche published minimal Type Metadata at the exact frozen vct URL; the endpoint returns HTTP 200 and application/json. The metadata identifies and displays the research credential type. It does not define a production issuer trust framework, establish implementation conformance, or version the profile. The frozen credential does not carry vct#integrity, so a consumer cannot infer a content-pinned metadata version from that credential. A deployment whose policy requires Type Metadata MUST still reject when it cannot retrieve or fully process the metadata through a trusted, profile-defined method. The action commitment proves equality to a declared action projection under a named byte profile. It does not prove that the relying party executed that description faithfully or that the real-world effect was semantically correct. The MachineMandate repository's embedded runtime-attestation fixtures use swtpm; the separate PCR-16 AAC/AEP composition instance uses a vTPM. Neither is a manufacturer-provisioned physical TPM claim. The formal three-owner IETF 126 evidence-generating run did not produce a valid result at the proposed 2026-07-23 coordinate because its complete pre-run freeze was not issued. Credential self-checks and engineering rehearsals remain separately classified; no successful composition result is claimed here. The first-instance MachineMandate CAN profile seed text was contributed by Anton Sokolov, Tyche Institute.

The WHO Slot: Named-Human Authorization The WHO slot answers a single question: which named, accountable human — or quorum of distinct humans — authorized this exact action before it ran. It is deliberately narrow. It does not define the composition model itself, a sufficiency or policy decision, a new audit-record format, or a replacement for agent or workload identity: "which agent acted" is a different slot, and "was this authorization sufficient for this action" is a layer above the composition. It binds the authorization to the exact observed action by the composition's shared action digest — the subject digest of the Composition Model — and exposes the binding metadata a composition verifier needs, and nothing more. Digest equality itself neither authorizes the action nor proves completeness. In the first-instance profile (, with the receipt format in ), the WHO record is an authorization receipt: a device-bound signature by a named principal — or a set of distinct principals — over the canonical bytes of one action, verifiable offline against the signer's public key. Any record form meeting the producer and verifier requirements below conforms. A conforming WHO producer MUST state: the authorizing principal identifier(s) — the named human(s), not the agent; for a quorum, the quorum descriptor (an M-of-N threshold or an ordered sequence) and the eligible or actual signer identifiers; the subject of the action being authorized; the covered action bytes or data model, the canonicalization rule (if any), the digest algorithm and version, and the domain-separation context; the binding between the subject digest and the receipt signature(s) — the signed payload MUST cover the digest; the validity window and any freshness or one-time-use semantics; and the failure behavior when a required binding input, signer, or quorum member is absent — fail closed: absence of authorization is not authorization. A conforming WHO verifier MUST be able to produce a result that states: whether each signature validates under the profile rules; the exact digest bytes it recomputed and the canonicalization and hash parameters used; whether the digest is covered by each signature; for a quorum, whether the threshold is met, whether the counted signers are distinct principals, whether every counted signer signed the same canonical action bytes under the same digest context, and — for an ordered quorum — whether the required order held; whether the receipt is within its validity window and any one-time-use constraint; and the verified-versus-accepted distinction (below). The verifier MUST keep signature validation, digest recomputation, quorum evaluation, and freshness as separate results, and MUST NOT collapse them into a single opaque "authorized" boolean. The WHO slot separates two claims a composition verifier must never conflate: VERIFIED — the signature(s) and the digest binding hold, given a public key; objective and offline — and ACCEPTED — the relying party additionally trusts the authorizing principal(s) via out-of-band key pinning; a relying-party decision, not a property of the receipt. A WHO verifier MUST surface these separately: a valid signature over the bound digest proves VERIFIED and never implies ACCEPTED, and neither implies the authorization was sufficient for the action. At the composition join, the WHO slot exposes a minimal, disclosure-aware reference: the subject digest and its declared digest context; the authorizing principal identifier(s) — or, under selective disclosure, a commitment to them; the quorum descriptor, if any, with a distinctness assertion; and the binding assertion that the signature(s) cover the subject digest. The reference carries no agent identity, no policy verdict, and no sufficiency claim. The WHO reference at the seam SHOULD carry a commitment to the authorizing principal identifier and not the identifier itself. The selected WHO profile MUST define a hiding commitment construction, its scope, its binding to the verified WHO record, and how an authorized verifier obtains any required disclosure. A plain deterministic hash of a principal identifier is not sufficient for concealment. Different commitments MUST NOT by themselves establish distinct humans. This commitment rule covers a principal reference in any slot, not only WHO. Where a WHO record is also registered to a transparency service (see Assurance Tiers), the transparency receipt proves registration of the submitted statement under the service policy; it does not prove that a named human authorized the action. A WHO verifier MUST keep native signature validation, digest recomputation, and transparency-receipt validation as separate results. In addition to the composition-level negative classes (see Conformance), a WHO profile MUST reject each of the following, and the verifier MUST report which check failed: semantically similar action input with different canonical bytes; a changed subject; a changed authorizing-principal reference; replay of the receipt under a different action (a different subject digest); a quorum satisfied by a non-distinct principal filling two slots; an ordered quorum satisfied out of order; a threshold not met; a mismatched or absent receipt signature; a signature that verifies but whose signed payload does not cover the subject digest (an unbound signature); a stale receipt; a post-hoc ratification presented as pre-execution authorization; a reusable authorization presented under one-time semantics, or a one-time authorization presented as reusable; and WHO digest bytes that do not match an adjacent slot's digest for the same claimed action under compatible digest contexts (per the binding rules of the Composition Model). The WHO slot's positive-vector classes are drawn from the shared composition vector (see Conformance); this document defines no WHO-specific positive vectors beyond that shared suite. For the ordering class — a post-hoc ratification presented as pre-execution authorization — the criterion for what closes the class is narrower than authentication. An ordering claim has two terms; an input closes it only if it comes from a source that observed both terms, or from two records whose producing boundaries can be related in a way that orders the two terms. An artifact produced on the authorizing side alone — however strongly authenticated — cannot close the class, because the boundary that produced it never observed the effect term. A signature timestamp from a trusted authority is the illustrating case: it is an authenticated ordering input for the signature, and still insufficient, because it observes the signature and not the effect. The exclusion therefore rules out a side, not an artifact type.

The WHAT Slot

Design Rule The WHAT slot answers one question: what terminal verdict did the agent system record for one action, and what, if anything, is known to have crossed the effect boundary. It is a byte-stable record of a producer-observed or producer-recorded outcome, not a replay of the action and not a re-execution of it. It does not establish that the action was permitted (CAN), that a named human authorized it (WHO), that the runtime enforcement claim held (AUDIT), that an independent external observer confirmed the effect, or that the action was semantically correct. Two separations carry the whole slot: a dispatched attempt MUST NOT be presented as a confirmed effect, and a record of an action MUST NOT be presented as an observation of its consequence. A conforming producer emits a WHAT record for every terminal verdict, including blocks, denials, refusals, errors, timeouts, and other non-executing outcomes. Recording only successful actions is not a conforming WHAT history. Completeness of the history is a property of the producing boundary, not of any single record, and no WHAT record asserts it. The first-instance WHAT profile is the Agent Action Capsule (): the signed payload of a SCITT Signed Statement recording one action, its verdict-level disposition, its effect state, and the assurance actually supported by the record. Any record form meeting the producer and verifier requirements below conforms.

Subject, Native-Record, and Additional Bindings A WHAT record carries a binding for each construction under which it participates in the composition. A binding is the triple (canonicalization algorithm, exclusion set, purpose label) -> digest together with the complete digest context required by the Composition Model. The generic construction and its registry treatment are specified in ; this section states what a WHAT profile does with it. Every binding a record carries MUST lie inside the signed payload and be covered by the signature. A binding carried only in an unprotected header is not a binding. Three binding roles are distinguished, and a record MAY carry more than one binding in the third role. The subject binding. The subject digest joins independently produced slot records for the same action. In the exercised AAC composition profile it is the unprefixed lowercase hexadecimal representation of SHA-256(JCS(action)) where action is the exact action object frozen by the composition vector and JCS is . The profile label, covered action field set, canonicalization profile, hash algorithm, absence of additional domain-separation bytes, and lowercase-hexadecimal representation are all part of the digest context. A producer MUST NOT substitute sha256:-prefixed text, raw digest bytes, a different action projection, or a human-readable rendering for that value. The native-record binding. The WHAT record is content-addressed by its own identifier — in AAC, capsule_id, recomputed under the Capsule profile's capsule_id derivation. The subject digest and the native-record identifier serve different roles: the first joins slots, the second identifies these bytes. Equality between them is neither required nor implied, and a verifier MUST NOT derive one from the other. Additional composition bindings — the self-reference. A WHAT profile MAY declare one or more further bindings over the same action under different constructions, so that a single record can participate in more than one join without either side re-canonicalizing the other's bytes. Each additional binding MUST carry its own complete digest context and its own purpose label. A verifier MUST NOT infer equality, derivation, or transitive coverage between any two bindings on the same record merely because they cover the same action, share a hash algorithm, or appear in the same signed payload. Two bindings on one record are two independent claims that happen to be co-signed. Purpose labels are profile-owned and namespaced; only labels used across profile boundaries are registered centrally. A verifier that encounters an unknown purpose label MUST report the binding as present and uninterpreted and MUST NOT fail the record on that ground. Verified-but-opaque is a result; unknown is not an error. The first defined additional binding is the action-equivalence binding, whose purpose is to answer "is this the same action" across producers and across time without requiring either party to disclose the action. It is computed over a declared action subset with its own exclusion set, and it MAY use a deterministic keyed derivation identified by an algorithm identifier and a key identifier, so that equal inputs yield equal digests within a key scope and unguessable digests outside it. Key management is out of scope; only the algorithm and key identifiers appear in the record. This construction MUST NOT be confused with the salted per-field commitments used for selective disclosure. Salted commitments use fresh random salt per value and therefore destroy equality by design, which is what makes concealment safe. A keyed equivalence derivation preserves equality within a scope by design. The two mechanisms have opposite purposes and MUST NOT share vocabulary in a profile's text or field names. A record MAY carry more than one equivalence binding under different purpose labels and key scopes — for example one scoped to a single producing operator and one scoped to a party pair. A single equivalence digest MUST NOT be presented as valid in more than one key scope. Signature-protected preimages. Where the bytes a binding covers are already fixed by a signature, the canonicalization is that signature's own byte boundary and re-canonicalizing is an error. A profile taking this option MUST identify the covered octets by citing a normative reference together with the name that referenced specification gives that exact byte sequence. If the container specification does not itself name the byte sequence, the profile MUST NOT rely on transmitted octets and MUST declare a canonicalization instead. Reproducibility bounds. A profile whose canonicalization admits numbers MUST state its integer magnitude bound. A canonicalization that permits integers outside the range representable exactly by an ECMAScript Number is not reproducible: two conforming verifiers may derive different digests from the same input. The exercised AAC profile rejects integers outside plus or minus (2^53 - 1) with a typed error and orders object members by UTF-16 code unit. A profile MUST also state its digest grammar in prose — for example, "exactly 64 characters, each in the set 0-9 and a-f" — and MUST NOT state it only as a regular expression. A grammar whose meaning depends on the reader's regular-expression engine is not a grammar.

Declared Field Basis A digest is comparable only with its digest context. A field value is comparable only with its declared basis. Any field a WHAT record exposes at the composition join, or that participates in a comparison, reconciliation, or aggregation across producers, MUST carry the basis under which its value is stated. This requirement is independent of the digest rules above and is not satisfied by them. At minimum: A quantity MUST declare its unit of measure, from a named and versioned unit vocabulary, and MUST NOT rely on a unit implied by a field name. A monetary amount MUST declare its currency, whether the amount is stated gross or net, the tax basis if any, and the rounding rule and precision applied. A time instant MUST declare which event the instant marks — for example request, dispatch, observation, or record creation — together with the time source and the scale and offset. An instant with no declared referent marks nothing. A rate or ratio MUST declare the basis of both its numerator and its denominator. A coded or enumerated value MUST declare the code list and its version. A field presented without its declared basis is not joinable. A verifier MUST report it as uncomparable and MUST NOT supply a local default, infer a basis from a field name, or convert between bases on the record's behalf. Silent unit and basis coercion is the failure mode this rule exists to make impossible, and it is the one most likely to survive every cryptographic check in this document. Where two profiles genuinely state the same quantity on different bases, they compose through an explicitly declared and digest-pinned mapping cited by both records, not through a verifier's local conversion. This document states the obligation; it does not define the vocabularies. A basis vocabulary — a unit list, a currency and rounding convention, a code list, or a declared mapping between two bases — is declared and versioned by the party that owns it and identified by a stable normative reference, as treats artifact-type declarations. A profile cites the vocabularies it uses rather than restating them. The division is deliberate and neither document repeats the other: that a joined field must declare its basis is a composition rule; how a basis vocabulary is declared, versioned, and cited is declaration machinery. A profile that cites no vocabulary for a basis it claims to declare has not declared one.

Producer Requirements A conforming WHAT producer MUST: identify the profile and serialization-suite versions in use; identify the action, the accountable operator, the agent developer and version, the timestamp with its declared referent and source, and the configuration epoch when one is used; carry a stable per-agent-instance identifier, distinct from the operator, the developer, and the configuration epoch, on every record; where fleet composition is sensitive this identifier is eligible for selective disclosure, and it is informational to a composition verifier; identify the tool or endpoint invoked and its version, so that a silent change in a tool's behavior is reconstructable after the fact; carry the subject binding and its complete digest context, and each additional binding with its own context and purpose label; name the counterparty the action was directed at — its class (agent, API, human, or none), its identity, and the cross-party rung actually attained — and carry the field even when the exchange was unilateral. The counterparty field is informational to a composition verifier and eligible for selective disclosure; it MUST NOT become a verifier-required field, because a profile MUST NOT permit concealment of a field its own verifier requires; carry the cross-party correlator over the request, where one exists, so that two parties' records for one exchange can be related without either disclosing the action; record the disposition — the decision, the approver class, the human-disposition value, and the verdict class — and carry any approval-scope declaration as a digest, leaving evaluation of that scope above the composition layer; record the effect status and the effect-assurance mode without collapsing either into the verdict class; emit a confirmed effect only when a response digest over the actually observed response is present. Where no response bytes were observed, the record MUST NOT rise above dispatched-unconfirmed, whatever the runtime believes happened; distinguish a pre-dispatch timeout from a post-dispatch timeout through the effect mode — not-applicable versus dispatched-unconfirmed — rather than through the verdict; carry an effect attestation whenever an effect was dispatched, and omit it when no effect occurred; state, for each field it exposes, whether that field is verifier-checked or informational, so that an implementer never has to guess which of the two a field is; and preserve later resolution of an unresolved outcome as a new signed, linked record rather than by mutating the original. Where a WHAT record cross-references a record in an adjacent slot, the signed payload MUST cover the adjacent profile's label, the referenced record's identifier, and a digest of the exact referenced bytes. That protected cross-reference demonstrates which record this one names. It does not import the adjacent slot's semantics and does not make a WHAT verifier a verifier of that slot. Profile-specific fields outside this document's vocabulary MUST be carried in a namespaced extension space rather than at the top level of the record, so that two independent extensions cannot collide and neither can be mistaken for core.

Verifier Requirements A conforming WHAT verifier MUST report separately: whether the record's signature validates under the selected trust input; whether the native-record identifier recomputes from the canonical record form; whether the subject digest recomputes from the frozen action under the declared digest context; whether the signed record carries that same subject digest; for each additional binding: whether it recomputes where the verifier holds the inputs, and — where it does not — that the binding is present and unverified, which is a distinct result from present and failed; whether every joined field carries a declared basis, and which fields did not; whether the confirmed-effect, verdict-and-effect, effect-attestation, and record-chain invariants hold; the record's native first-class verification result; any manifest-dependent secondary result, without allowing it to weaken or overwrite the first-class result; and the relying party's acceptance result together with the policy inputs that produced it. These results MUST NOT be collapsed into a single opaque executed, verified, or accepted boolean. A valid record proves that the signer made the bound WHAT statement. A runtime-claimed effect remains a runtime claim; it does not become an independent observation because the record is signed, registered, or anchored. A verifier MUST distinguish three terminal outcomes when comparing this record against a counterparty record for the same action: reconciled, where the compared fields agree under compatible declared bases; divergent, where they disagree, with the divergence located to a named field and quantified; and indeterminate, where no declared mapping between the two bases exists. Divergence is a reportable result carrying both parties' evidence, not a verification failure, and MUST NOT be rendered as one. An unresolvable linkage is indeterminate, not divergent. Where a verifier cannot produce pass or fail, it MUST report the applicable non-binary result (see Result vocabulary) and MUST NOT collapse distinct causes. A check that was not attempted because a prerequisite or required input was unavailable is not_evaluated; a required profile or semantic rule the implementation does not support is unsupported; and a comparison over readable declared inputs that cannot be resolved is indeterminate. Key-scope unavailability — a verifier that is not party to the key scope an equivalence or comparison value was produced under — is a required-input case: it MUST be reported as not_evaluated, not indeterminate. This document states that classification directly, rather than leaving it to each profile to decide, precisely because a per-profile choice would let independent implementations classify the same vector differently.

Cross-Party Rungs Where a WHAT record names a counterparty, it MUST state the rung actually attained, drawn from an ordered vocabulary in which no rung is confusable with another and no rung is inferred from the absence of evidence for a higher one. This document does not define that vocabulary. The bilateral attestation work establishes the base distinction between a fully-bilateral record and a reduced-assurance one; a WHAT profile cites the vocabulary it uses rather than restating it, and a profile that cites no vocabulary has not declared a rung. What this document states is the structural discipline any such vocabulary must satisfy, which holds whatever names are chosen: the rungs are ordered; a consumer MAY require a minimum; a record claiming a higher rung than its carried evidence supports is an overclaim and MUST fail; and an unknown rung value grades down to the lowest rung and never up, so that a verifier which does not recognize a rung under-reads the record rather than over-trusting it.

Composition and Transparency Seams At the composition join, a WHAT profile exposes: the profile label and version; the subject digest with its complete digest context; each additional binding with its purpose label and context; the native-record identifier and its context; the disposition and verdict class; the effect status, effect mode, and effect-attestation grade; the counterparty class and attained rung, subject to selective disclosure; the declared basis for every exposed field; the native and secondary verification results; any protected cross-reference to adjacent slot evidence; and the relying party's final WHAT result with its policy inputs. If the record is registered with a SCITT Transparency Service, the receipt supplies the separate receipt-payload digest. The receipt proves registration of the submitted statement under the service policy. It does not prove that the record is complete, that its effect claim is true, that an authorization existed, or that the relying party should accept the action.

Negative Vectors In addition to the composition-level negative classes, a WHAT profile MUST include vectors for at least: a subject digest recomputed from different action bytes; a record whose signed subject digest differs from the composition digest; a native-record identifier that does not recompute; an additional binding whose purpose label is present but whose context is absent; two bindings on one record treated by the verifier as equal, derived, or transitively covering, without demonstration; an equivalence digest presented as valid in a second key scope; an equivalence digest colliding across genuinely different actions, and failing to match across genuinely identical ones; a joined field carrying a value with no declared basis; two records compared across incompatible bases and reported as reconciled; a divergence rendered as a verification failure, or an unresolvable linkage rendered as a divergence; a changed disposition or effect after signing; a confirmed effect without a response digest over the observed response; a non-dispatching verdict paired with a dispatched or confirmed effect; a post-dispatch timeout presented as not-applicable; a missing effect attestation when dispatch occurred, or an effect attestation present when no effect occurred; a broken or ambiguous supersession chain; a counterparty rung claimed above the evidence carried — in particular full-bilateral claimed with one signature; an absent counterparty field on a directed action; a protected cross-reference bound to different adjacent-slot bytes; a transparency receipt bound to a different signed statement; an integer outside the profile's stated magnitude bound admitted into a digest field; and an unknown registry value treated either as a stronger assurance grade or as an automatic verification failure. Every negative vector ships with its condition-removed mutant, so that a check which silently stopped running is distinguishable from a check that passed.

Current Assurance Boundary The exercised first-instance vectors verify the WHAT record and the composition join. They do not establish that every consequential action was recorded, that a runtime-claimed effect occurred in the external world, or that an independent observer corroborated the result. An independent meter, auditor, or other observer supplies a separate signed claim over the same subject digest at the composition layer; it is not silently promoted into the WHAT record. The first-instance WHAT profile and its text are maintained by Steven Mih, Action State Group, as the Agent Action Capsule author.

The AUDIT Slot

Design Rule The AUDIT slot asks whether the runtime produced independently appraisable evidence that its declared enforcement path was applied to this action, in the claimed causal order, without undetected alteration. It does not establish that the policy was sufficient, that every relevant event was recorded, or that the action was semantically correct. Those are separate completeness and relying-party judgments. Platform attestation also does not, by itself, prove the truth of an application-layer record; the binding between the two is the load-bearing claim. The first-instance AUDIT profile composes an application-layer action evidence package (AEP) with RATS Evidence and an Attestation Result (, using the roles and trust model of ). The AEP is a signed, append-only record of the action, its authority, and its outcome. Platform Evidence binds an AEP outcome digest and a fresh per-appraisal value into data covered by an attestation-key signature. The resulting profile lets a verifier check that the same outcome named by the action record was present in the appraised execution context. It does not make the AEP producer or the Attester a truth oracle. An implementation of the Governance Audit Record (GAR) can supply the AEP role in this profile when the selected GAR artifact, including any referenced Event Log records, records the action, its authorizing principal, and its outcome; validates under a signed, append-only, tamper-evident chaining construction; and the platform-evidence profile demonstrates that the GAR-producing component and the action-performing component are within the measured software stack claimed by the appraisal. supplies the platform-attestation binding for evidence meeting those conditions; it does not define or require a replacement record format. Other implementations may fill the same AEP role. Where the authorizing principal a GAR artifact records appears at the seam, it is a principal reference and follows the commitment rule of . The signed, append-only, chaining construction and causal-ordering properties referenced above are specified in , §6 (Session Audit Record), §8 (Event Log Requirements), and §12 (Authority Lifecycle Events). (-03) carries these sections forward without reproducing them and adds the OTel semantic convention and GAR Processor specification.

Producer Requirements A conforming AUDIT producer MUST state: the covered action and outcome fields; the subject-digest context defined in the Composition Model; the AEP signature and chaining construction; the predecessor or sequence value that establishes the claimed causal order; and the general obligation: the exact transformation that binds the outcome digest into the named profile's execution-context evidence, stated precisely enough that a third party can recompute that binding without additional information from the producer. The general obligation's digest reaches every value the named profile obliges the declaring party to supply or name, in the order the profile enumerates them. A producer MUST NOT satisfy the general obligation by naming a profile without enumerating the values that profile's own Producer Requirements requires (see "AUDIT Profile: Platform Attestation").

Exercised PCR-16 Binding One exercised AEP/AAC binding folds the raw 32-byte action-response digest from an Agent Action Capsule () into TPM PCR 16, starting from the all-zero PCR value, and places the action capsule identifier in the TPM quote's extraData. For SHA-256 this yields: PCR16 = SHA-256(0x00 * 32 || response_digest) The PCR selection is an instance parameter: this AEP/AAC interop vector uses PCR 16, while the separate Project Veraison exercise documented in uses PCR 4. The quote's signed pcrDigest then commits to the selected PCR value. A profile using this construction MUST distinguish the raw response-digest bytes from their 64-character hexadecimal display form, identify the PCR selection, and state whether extraData carries a fresh challenge, a unique action identifier, or another binding value. An identifier provides freshness only when the relying-party policy ensures that it is fresh for the appraisal.

Verifier Requirements A conforming AUDIT verifier MUST report separately: whether the AEP signature and hash chain validate, including predecessor and sequence checks; the subject and outcome digest bytes it recomputed, with their digest contexts; and whether it can recompute the named profile's binding between the outcome digest and that profile's execution-context evidence, using only the values the profile's Producer Requirements obliges the producer to supply. These checks MUST NOT be collapsed into one opaque "audited" boolean. A profile's verifier reports add to these reports and do not replace them.

Composition and Transparency Seams At the composition join, the AUDIT slot exposes the subject digest and context, the profile label, the authority-reference digest for the native AEP/RATS evidence, the appraised outcome digest, the freshness result, and the native appraisal result. If the evidence or a detached digest of it is registered with a SCITT transparency service, its receipt supplies the separate receipt-payload digest. The receipt proves registration under the service's policy; it does not prove that the runtime enforced correctly, that the attestation was fresh, or that the relying party should accept it.

Negative Vectors In addition to the composition-level negative classes, an AUDIT profile MUST include vectors for at least: a changed action or outcome after signing; a broken or reordered AEP chain; ASCII hexadecimal text substituted for raw digest bytes; and a transparency receipt bound to a different payload. The following are specific to the AUDIT Profile: Platform Attestation (see below) and MUST be included by any profile using its platform-Evidence construction: a changed PCR selection (Platform Attestation profile); a PCR value inconsistent with the declared extension (Platform Attestation profile); a quote signature that does not validate (Platform Attestation profile); a quoted outcome different from the action record's outcome (Platform Attestation profile); a replayed quote whose signed freshness value differs from the expected value (Platform Attestation profile); and an affirming Attestation Result paired with the wrong action evidence (Platform Attestation profile).

Current Assurance Boundary The exercised first-instance vectors use a virtual TPM (vTPM), including appraisal by a locally operated Project Veraison instance. They exercise genuine TPM 2.0 quote structures, attestation-key signatures, digest binding, appraisal, and negative cases. The evidence bundle does not establish a manufacturer-provisioned physical TPM root for that vTPM and therefore does not establish a hardware-rooted guarantee, production readiness, conformance by the Veraison project, or endorsement by it. A hardware-backed profile would additionally need to establish its attestation-key provenance, Endorsements, Reference Values, measured workload coverage, and deployment-specific trust policy. The swtpm-based exercise validates the verifier logic and evidence plumbing; it is not evidence of a hardware root of trust. The first-instance AEP/RATS AUDIT profile and this slot text were contributed by Anton Sokolov, Tyche Institute.

AUDIT Profile: Platform Attestation (first named profile) This is the first profile named against the AUDIT slot's general obligation above. It composes an application-layer action evidence package (AEP) with RATS Evidence and an Attestation Result, per the Design Rule and Exercised PCR-16 Binding described earlier in this section.

Producer Requirements A conforming Platform Attestation AUDIT producer MUST state: the covered action and outcome fields; the subject-digest context defined in the Composition Model; the AEP signature and chaining construction; the predecessor or sequence value that establishes the claimed causal order; the platform Evidence format and selected measurements; the exact transformation that binds the outcome digest into those measurements; the attestation key and its trust-chain inputs; the freshness value and where it appears in signed Evidence; the Verifier and appraisal scheme; and any Reference Values, Endorsements, or policy inputs needed to reproduce the appraisal.

Verifier Requirements In addition to the reports required in , a conforming Platform Attestation AUDIT verifier MUST report separately: whether the attestation signature validates under the supplied attestation key and whether that key is accepted under the relying party's trust policy; whether the quoted PCR digest matches the selected PCR values and whether the declared outcome-to-PCR transformation recomputes; whether the outcome digest extracted from the action record equals the digest bound into the signed platform Evidence under compatible contexts; the Verifier's native appraisal result; whether freshness was actually enforced by comparing the value recovered from the raw signed Evidence with the expected per-appraisal value; and the relying party's final acceptance result and policy inputs. These checks MUST NOT be collapsed into one opaque "audited" boolean. In particular, an affirming Attestation Result is not evidence of freshness unless the selected appraisal scheme checked the relevant nonce or the relying party performed and reported that comparison separately. Re-deriving freshness from the raw TPM quote bytes is therefore a distinct check when the Attestation Result does not expose or enforce the quote's signed extraData.

Assurance Tiers A record answering these questions may be produced at different assurance levels, and the distinction is the crux for a relying party who does not trust the operator: Self-attested (baseline). The record is signed by the agent or its operator and held by an interested party. This is useful telemetry and a reasonable default, but it cannot, by itself, satisfy a regulator, counterparty, or insurer who does not trust the producer. Anchored / third-party-verifiable. The record, or a digest of it, is registered to a transparency service — the SCITT substrate () — yielding a receipt that lets a party who trusts neither the agent nor the operator verify the record's existence, its content at registration time, and non-equivocation, independent of any single producer's infrastructure. This document does not mandate the anchored tier; self-attestation remains valid. It specifies how any conforming profile MAY reach the anchored tier by registering to a transparency service, and how that tier is tested (see Conformance) — so that third-party-verifiability is a property profiles can converge on, not a single format they must adopt.

Conformance Conformance is expressed as a shared vector suite: a positive composition vector (one action threaded through the populated slots) plus, per slot, the negative-case classes it MUST expose (e.g. non-deterministic encoding, ASCII-hex-as-bytes, profile-label mismatch, receipt bound to a different statement, broken join digest). A conformance vector freezes only after it has been recomputed by at least two independent implementations. This document specifies no implementation; each slot is implemented independently, and any party may verify against the vectors.

Cross-Slot Conformance Mechanism The cross-slot mechanism in this section was contributed by Iman Schrock (EMILIA Protocol, Inc.). Its first runnable pack — one positive four-slot vector, thirteen negative cases, and thirteen condition-removed controls, with manifests, checksums, an executable runner, and an external-report template — is published in the EMILIA Protocol repository (pull request 521, commit 30916c80). That manifest pins Composition -00; it was not built against this -02 revision, and an -02-pinned manifest is future work, out of scope here. Per the freeze rule below, the pack is a candidate, not a frozen result, until a second implementation maintained by a different party consumes the same published bytes and returns the completed external report.

Boundary The mechanism tests whether an implementation preserves the declared boundaries and joins of the Composition Model. It does not define native conformance for CAN, WHO, WHAT, or AUDIT. Each slot owner maintains the rules and vectors for that slot. Composition imports the native reports without weakening, relabeling, or overwriting them. A run reports the CAN, WHO, WHAT, and AUDIT results separately, followed by each cross-slot check. It never collapses those results into one opaque trusted, authorized, executed, or verified boolean. CAID, AEC, and AEB each have one normative home, independently maintained by Iman Schrock (EMILIA Protocol, Inc.): Mechanism Normative home Scope CAID The exact material-action identifier and declared digest context AEC Native evidence preservation and relying-party requirement satisfaction AEB Executor-side local authorization, atomic reserve/consume, invocation, and post-dispatch outcome handling Composition consumes each mechanism's named outputs at the interfaces below. It does not replace or inherit CAID, AEC, or AEB; those mechanisms remain independently maintained by their own documents, not by this one. CAID, AEC, and AEB enter at distinct interfaces rather than becoming new slot definitions: CAID supplies the declared exact-action digest context. AEC preserves native evidence verification and reports whether a named relying-party requirement is satisfied. AEB remains the executor-side authorization, reserve/consume, invocation, and post-dispatch uncertainty lifecycle. Agent Action Capsule supplies a candidate WHAT record under its own native Class 1 and Class 2 conformance rules. The cross-slot mechanism tests those interfaces. It does not replace their specifications or move enforcement into an evidence record. An AEB result remains bounded by its selected native source and trust assumptions; runtime-enforcement evidence is not automatically independent evidence that an external effect occurred. Mechanism references and run pins serve different purposes. Each native report retains its exact specification, verifier, adapter, trust-input and result-artifact pins, and its original result meanings. Equal status labels across revisions MUST NOT be treated as equal evidence claims. A change to a selected native interface requires new manifest expectations and the applicable native-profile review before the corresponding run can be frozen. The current CAID -04 , AEC -07 , and AEB -07 are informative reference-transition targets, not a jointly frozen suite adopted here. CAID -04 adds input-admission and definition/snapshot rules; AEC -07 separates cryptographic VERIFIED from relying-party ACCEPTED and changes its replay contract. A historical combined verification result does not retrospectively supply those separate results. AEB -07 makes CAID conditional on a cross-format join and AEC conditional on a multi-leg requirement, and adds native authorization-handoff, replay-identity and same-action-fence requirements. Those executor requirements are not established by an offline composition join. The older normative pins above remain unchanged pending selection of the consuming contracts and review of their dependency closure. AEB -07 itself pins CAID -02 and AEC -06 normatively; replacing all three top-level references with the latest revisions would not establish a compatible native adapter. The transition review must select exact definitions, snapshots, suites, mapping profiles, result schemas and replay contracts, and retain the corresponding native verification evidence. No historical run is upgraded by this informative comparison, and no native mechanism conformance is claimed by the candidate runner.

Bundle requirements Every bundle pins: the Composition revision and digest; each populated slot's profile and serialization-suite revision; the exact action bytes and complete digest context; every native record as bytes, with its native identifier and digest; each additional binding, purpose, context, and verification expectation; every protected cross-reference and the exact referenced bytes; each compared field's declared basis and any pinned mapping; the expected result of every native and join check; and the expected terminal composition report. A runner evaluates the supplied bytes. It does not substitute a reconstructed fixture, upgrade an unknown profile, or infer an absent mapping, field basis, purpose label, or digest representation.

Result vocabulary Every named check returns exactly one of: pass — evaluated and the condition held; fail — evaluated and the condition did not hold; not_evaluated — a prerequisite failed or the check was not attempted; unsupported — the pinned required profile or semantics are not implemented; or indeterminate — the records are readable, but the comparison cannot be resolved from the declared inputs. Only pass is a pass. The other four values are never silently upgraded. A rejected prerequisite does not turn unexecuted downstream checks into extra failures. An unknown optional binding may remain structurally readable. It cannot satisfy a policy that requires understood semantics for that binding.

Run report A report contains: implementation owner, name, version, and source revision; bundle and input-artifact digests; each native slot result unchanged; each native slot and join's expected and actual result; divergence located to a named field, including both values and bases; the terminal composition result; deterministic report digest computed over the report with the report_digest member omitted; and known shared dependencies that limit independence. Matching a bundle proves conformance only to those pinned vectors. It does not certify an agent, prove every action was recorded, establish an external effect, or replace a relying party's policy decision.

Positive, negative, and condition-removed vectors The first pack contains one positive four-slot vector and the following negative cases. Every negative has a condition-removed twin that changes only the tested defect and returns to pass. ID Changed condition Required result COMP-BIND-01 Different action bytes retain the positive digest fail COMP-BIND-02 Incompatible digest context or action projection indeterminate COMP-BIND-03 Raw bytes and lowercase hexadecimal are confused fail COMP-BIND-04 Protected reference names different slot bytes fail COMP-BIND-05 Additional binding omits its context fail COMP-BIND-06 Unknown optional semantics are required by policy unsupported, binding remains readable COMP-BASIS-01 Compared field lacks a declared basis indeterminate COMP-BASIS-02 Incompatible bases lack a pinned mapping indeterminate COMP-RESULT-01 Native and join results are collapsed fail COMP-RESULT-02 Composition overwrites a native result fail COMP-JOIN-01 Valid records identify different actions fail COMP-JOIN-02 not_evaluated is relabeled as verifier failure fail COMP-UNKNOWN-01 Unknown required profile is treated as accepted unsupported The runnable pack therefore contains 27 cases: one positive, thirteen negatives, and thirteen condition-removed controls. This is the EMILIA-delivered, Composition-00-pinned pack described under Delivered and open; it is not rebuilt here (see below). New for this revision, not yet in the delivered -00 bundle. Verifier Requirements draws a three-way discrimination between not_evaluated, unsupported, and indeterminate. Checking the delivered pack against that discrimination: COMP-UNKNOWN-01 already exercises unsupported (an unrecognized required profile), and COMP-BASIS-01/COMP-BASIS-02 already exercise indeterminate (readable declared inputs whose comparison cannot be resolved). No delivered case exercises producing not_evaluated from an actually-missing required input — COMP-JOIN-02 only forbids mislabeling not_evaluated as failure, it does not test the case that produces it. This revision therefore specifies one additional vector to close that gap, to be picked up by the future -02-pinned manifest along with the rest of the pack: ID Changed condition Required result COMP-JOIN-03 Required input for a check is absent from the bundle not_evaluated COMP-JOIN-03 is two-sided: its condition-removed twin supplies the missing input and returns the check to pass, changing only the tested defect, matching every other row's discipline. When the -02-pinned manifest is built, the runnable pack becomes 29 cases: one positive, fourteen negatives, and fourteen condition-removed controls.

Freeze rule A vector freezes only after two implementations maintained by different parties consume the same published bytes and produce reports matching every pinned expectation. Sharing a library, generated fixture, or expected-output file does not establish independent recomputation unless that dependency is the declared object under test. Changing an input byte, profile pin, expectation, canonicalization rule, or mapping creates a new bundle and restarts the independent-run requirement.

Delivered and open EMILIA delivers: the mechanism in this document; the manifest and exact four-slot input bytes; the 27-case bundle and executable runner; the EMILIA report and checksums; and an external-report template for the second implementation. The pack is Composition-00-pinned candidate evidence, not a frozen independent result, until an independently maintained second implementation reports against the same bytes. The remaining step is an external implementation run over the same bytes. The author baseline capture reported on 27 September 2026 has no retained raw output or environment record that can substantiate it. It is not used as independent run evidence. The 26 September 2026 null rerun remains email-confirmed without retained raw logs. Neither email reconstructs an execution artifact or satisfies the independent-implementation freeze rule. An EP three-computation cross-implementation row is omitted from the interoperability evidence: no pinned implementation, input, command and result coordinates currently substantiate that row. This omission does not change the composition mechanism; a future row requires its own reproducible run and owner confirmation. Capsule Class 2 remains native to the Capsule implementation and requires its producer manifest and bound private evidence; the cross-slot harness does not manufacture those inputs.

Extension Points Additional question-slots compose by the same digest discipline. Belief-provenance ("why the agent believed what it acted on") is a named extension socket. Other extension slots may be named as later documents identify a further independently-verifiable question that composes by the same shared-digest discipline; naming one here is not a commitment to define it in this document.

Relationship to Existing Work This document complements, rather than replaces, existing efforts. An architecture for auditing agent delegation and interactions is developed separately (, with its interaction, action, delegation, and authorization-transition record types); record and logging formats and action-lineage protocols are defined in adjacent documents (e.g., , , — cited as live adjacent work, not positioned). The four questions here map onto those record types rather than redefining them. A deterministic action-identifier construction for the WHAT question is specified independently in . It is an adjacent instantiation of the WHAT slot — cited as live adjacent work, not positioned; the WHAT profile exercised here remains the one named in that slot. What this document adds is the piece those leave open: the composition of independently-verifiable profiles by a shared action-digest, a shared conformance-vector suite, and the anchored, third-party-verifiable assurance tier (see Assurance Tiers). It defines no new signing, transport, or transparency mechanism; the specific documents for that discipline are cited normatively and informatively throughout (see, e.g., Cross-Slot Conformance Mechanism for the CAID, AEC, and AEB references).

Security Considerations The security properties are those of the composed profiles plus the binding rules here; no single layer suffices. The agent is not trusted. Distributed trust roots mean no single verifier or transparency service is assumed sufficient. This document does not address an adversarial party that refuses to record at its own boundary, nor collusion across all roles, nor model alignment. Key management, trust-anchor distribution, and revocation are each constituent profile's responsibility and are out of scope here; this document only requires that a profile state which trust inputs a verifier needs and report when they are unresolved (see, e.g., each slot's own Verifier Requirements). A verifier MUST NOT treat digests computed under different digest contexts (see Digest Context and Representation) as equivalent absent a stated mapping between them; doing so is a composition-layer vulnerability, not a supported interoperability path. Each slot's own Negative Vectors and Current Assurance Boundary subsections state further slot-specific threats and non-goals not restated here.

Privacy Considerations Records may be rich in information about users and the data an agent processed. Profiles SHOULD support content-private, hash-only (detached-payload) records so a registered statement carries only a digest, with content held under deployment controls. The shared join digest enables cross-slot correlation; pairwise or encrypted correlation identifiers SHOULD be available where correlation is not required. Producer context admitted to any WHAT-leg record follows the data-admission tiers defined in the Privacy Considerations of . Profiles MUST distinguish native evidence provided to authorized verifiers from the public registration projection, and define the public fields, disclosure policy, correlation scope, and integrity-protected binding between them. Hash-only registration also needs review of public headers and correlators; it does not by itself establish unlinkability. This document does not itself define a data-minimization or retention policy; each constituent profile states its own admitted fields and any selective-disclosure mechanism it supports. A relying party or transparency service operator remains subject to applicable data-protection law for any personal data a record carries, regardless of the assurance tier at which the record was produced.

IANA Considerations This document has no IANA actions. A registry of slot identifiers and profile labels may be proposed in a later revision if cross-document coordination needs one; this document reserves no such registry now.

In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. EMILIA Protocol, Inc. EMILIA Protocol, Inc. EMILIA Protocol, Inc. EMILIA Protocol, Inc. EMILIA Protocol, Inc. EMILIA Protocol, Inc. Traceability in supply chains is a growing security concern. While Verifiable Data Structures (VDSs) have addressed specific issues, such as equivocation over digital certificates, they lack a universal architecture for all supply chains. This document defines such an architecture for single-issuer signed statement transparency. It ensures extensibility and interoperability between different transparency services as well as compliance with various auditing procedures and regulatory requirements. In network protocol exchanges, it is often useful for one end of a communication to know whether the other end is in an intended operating state. This document provides an architectural overview of the entities involved that make such tests possible through the process of generating, conveying, and evaluating evidentiary Claims. It provides a model that is neutral toward processor architectures, the content of Claims, and protocols. Ericsson Fraunhofer SIT Rama CyberSecAI Ltd SVT Robotics EMILIA Protocol, Inc. EMILIA Protocol, Inc. Action State Group, Inc. Action State Group Tyche Institute Action State Group, Inc. Meridian Verity Group Tyche Institute MyAuberge K.K. MyAuberge K.K. Cryptographic operations like hashing and signing need the data to be expressed in an invariant format so that the operations are reliably repeatable. One way to address this is to create a canonical representation of the data. Canonicalization also permits data to be exchanged in its original form on the "wire" while cryptographic operations performed on the canonicalized counterpart of the data in the producer and consumer endpoints generate consistent results. This document describes the JSON Canonicalization Scheme (JCS). This specification defines how to create a canonical representation of JSON data by building on the strict serialization methods for JSON primitives defined by ECMAScript, constraining JSON data to the Internet JSON (I-JSON) subset, and by using deterministic property sorting. This document defines two strategies for handling long lines in width-bounded text content. One strategy, called the "single backslash" strategy, is based on the historical use of a single backslash ('\') character to indicate where line-folding has occurred, with the continuation occurring with the first character that is not a space character (' ') on the next line. The second strategy, called the "double backslash" strategy, extends the first strategy by adding a second backslash character to identify where the continuation begins and is thereby able to handle cases not supported by the first strategy. Both strategies use a self-describing header enabling automated reconstitution of the original content. This specification defines a mechanism for the selective disclosure of individual elements of a JSON data structure used as the payload of a JSON Web Signature (JWS). The primary use case is the selective disclosure of JSON Web Token (JWT) claims. MATTR Authlete Inc. Ping Identity Tyche Institute Meridian Verity Group

Changes from -01 This -02 revision consolidates the fold list assembled 2026-09-12 from the co-author thread (Songbo Bu, Iman Schrock, Anton Sokolov, Tom Sato) and the 2026-08-17 AUDIT thread (Henri, Anton Sokolov, Joel). Landed in this revision: AUDIT mechanism-neutral split (Henri, 2026-08-17; Anton Sokolov, 2026-08-17 and 2026-08-20): §6.4.2/§6.4.4 restate the Producer/Verifier Requirements as a profile-neutral general obligation; the original ten-item Producer Requirements and eight-item Verifier Requirements lists move unchanged under a new "AUDIT Profile: Platform Attestation (first named profile)" subsection; §6.4.6 Negative Vectors labels the six attestation-specific classes as that profile's. The Verifier Requirements split was refined on 2026-10-04 (below). Digest-coverage rule (Joel, 2026-08-20; accepted by Anton Sokolov): the general obligation's digest reaches every value the named profile obliges the declaring party to supply or name, in the order the profile enumerates them. Principal-binding review (Songbo Bu, 2026-08-18, 2026-09-01, 2026-09-10): the Cross-Profile Reviews entry preserves -03 as the historical review input and records the scoped comparison against the published -06 revision, including its additional claim-grounding, outcome, dependency, and C-002 evidence requirements. The historical finding and no-byte-agreement boundary remain; see Principal-Binding Review (Bu). The bibliography remains pinned to -03 for that historical input. INTEROP.md PB row (Songbo Bu, 2026-09-01; Iman Schrock, 2026-09-10): Status changed to confirmed (Songbo Bu, 2026-08-18), with the no-byte-agreement limitation kept verbatim. The evidence-ladder Status key now distinguishes a recorded run from confirmation by a named counterparty. Change-sheet correction (Iman Schrock, 2026-09-01): §8.1 (Cross-Slot Conformance Mechanism) is already normative as of -01; it is not a "promote to normative" item, and its evidence boundary (Delivered and open) stands unchanged. V1 27-case pack status (Iman Schrock, 2026-09-01): described as Composition-00-pinned candidate evidence until an independently maintained second implementation reports against the same bytes. Evidence coordinates (Songbo Bu, 2026-10-03; Iman Schrock, 2026-10-02): the EP three-computation row is removed from INTEROP.md and from the interoperability evidence, since its commit coordinate does not resolve; the 27 September 2026 baseline capture is not used as independent run evidence, and the 26 September 2026 null rerun is recorded as email-confirmed without retained raw logs; CAID -04, AEC -07 and AEB -07 are added as informative transition references while CAID -02, AEC -05 and AEB -03 remain the normative pins; the WHAT question is restated as the outcome the agent system recorded and what is known to have crossed the effect boundary; the APS INTEROP row carries pinned run coordinates and names its pending counterparty. idnits (Songbo Bu, 2026-09-01, 2026-09-10): the earlier document-date correction is retained. OpenID4VP and MACHINE-MANDATE are cited in body text. Fresh offline lint on the 3 October 2026 local review candidate nevertheless reports unused-reference diagnostics for both; those diagnostics remain in the matching lint record for maintainer review, rather than being represented as a clean lint result. AUDIT verifier reports stated once (Anton Sokolov, 2026-10-04): the two mechanism-neutral checks (AEP signature and chain; recomputed subject and outcome digests) are stated only in §6.4.4, whose last sentence now says a profile's verifier reports add to these and do not replace them; §6.4.8.2 opens "In addition to the reports required in §6.4.4" and lists only the profile's own reports. No check is required of fewer verifiers. References and reference accuracy: Agent Action Capsule -02 to -05, payload binding -01 to -06 (now titled "Canonicalization Declaration for SCITT Signed Statements"), bilateral attestation -01 to -03. Four sentences describing those documents were corrected to match the cited revisions: basis vocabularies are declared and versioned by their owners (payload binding -06 defines no artifact-type registry); the bilateral work establishes the fully-bilateral / reduced-assurance distinction rather than rung names; the native-record binding names the Capsule profile's capsule_id derivation instead of a "JSON-DIGEST construction"; the privacy cross-reference names the Capsule profile's data-admission tiers instead of a "floor". Principal references at the seam (Blake Morrison, Iman Schrock; repository issue 10): the WHO reference at the seam SHOULD carry a commitment to the authorizing principal identifier rather than the identifier; the selected WHO profile MUST define the hiding commitment construction; a plain deterministic hash is not sufficient for concealment; different commitments do not by themselves establish distinct humans. The rule covers a principal reference in any slot, and the CAN and AUDIT (GAR principal) text cites it. Privacy Considerations now requires profiles to separate native evidence for authorized verifiers from the public registration projection, and notes that hash-only registration does not by itself establish unlinkability. Editorial: revision bumped from -01 to -02; document date pinned to the cut date; the -00-manifest self-reference in Cross-Slot Conformance Mechanism now names this -02 revision instead of -01. Not landed in this revision: EAR/EAT terminology (Songbo Bu, 2026-08-19; underlined by Anton Sokolov, 2026-09-03): no sentence in this revision cites a second AUDIT discharge path for the correction to attach to. It was not in the 2026-08-31 cut for the same reason: not deferred, no referent yet. The regulatory-motivation paragraph (Songbo Bu, 2026-09-01) is prepared as a separate commit pending Tom Sato's confirmation of his own section text (see the co-author thread).

Acknowledgments Mikhail Sergeev contributed the ordering criterion for the second-class verification result in the WHO slot: an input closes an ordering claim only if it comes from a source that observed both terms of the claim, or from two records whose producing boundaries can be related in a way that orders the terms (see The WHO Slot). That wording is his, offered as an IETF Contribution under BCP 78 and BCP 79. Blake Morrison proposed the commitment-first WHO reference at the seam and its extension to principal references in every slot, and reviewed the fields each slot places at the seam for linkability (repository issue 10). The authors also thank the reviewers of the -00 and -01 revision packages, whose byte-level review discipline this revision was built against.