3697 lines
118 KiB
Plaintext
3697 lines
118 KiB
Plaintext
|
||
|
||
|
||
|
||
Network Working Group C. Nennemann
|
||
Internet-Draft Independent Researcher
|
||
Intended status: Standards Track 20 May 2026
|
||
Expires: 21 November 2026
|
||
|
||
|
||
Agent Context Token (ACT)
|
||
draft-nennemann-act-01
|
||
|
||
Abstract
|
||
|
||
This document defines the Agent Context Token (ACT), a self-contained
|
||
JWT-based format that captures the full invocation context of an
|
||
autonomous AI agent — its capabilities, constraints, delegation
|
||
provenance, oversight requirements, task metadata, and DAG position —
|
||
and unifies authorization and execution accountability in a single
|
||
token lifecycle. An ACT begins as a signed authorization mandate and
|
||
transitions into a tamper-evident execution record once the agent
|
||
completes its task, appending cryptographic hashes of inputs and
|
||
outputs and linking to predecessor tasks via a directed acyclic graph
|
||
(DAG). ACT requires no Authorization Server, no workload identity
|
||
infrastructure, and no transparency service for basic operation.
|
||
Trust is bootstrapped via pre-shared keys and is upgradeable to PKI
|
||
or Decentralized Identifiers (DIDs). ACT is designed for cross-
|
||
organizational agent federation in regulated and unregulated
|
||
environments alike. ACT is the general-purpose agent context
|
||
primitive; the WIMSE Execution Context Token (ECT)
|
||
[I-D.nennemann-wimse-ect] is a sibling profile specialized for
|
||
workload-identity-bound execution recording in WIMSE deployments.
|
||
|
||
Status of This Memo
|
||
|
||
This Internet-Draft is submitted in full conformance with the
|
||
provisions of BCP 78 and BCP 79.
|
||
|
||
Internet-Drafts are working documents of the Internet Engineering
|
||
Task Force (IETF). Note that other groups may also distribute
|
||
working documents as Internet-Drafts. The list of current Internet-
|
||
Drafts is at https://datatracker.ietf.org/drafts/current/.
|
||
|
||
Internet-Drafts are draft documents valid for a maximum of six months
|
||
and may be updated, replaced, or obsoleted by other documents at any
|
||
time. It is inappropriate to use Internet-Drafts as reference
|
||
material or to cite them other than as "work in progress."
|
||
|
||
This Internet-Draft will expire on 21 November 2026.
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 1]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
Copyright Notice
|
||
|
||
Copyright (c) 2026 IETF Trust and the persons identified as the
|
||
document authors. All rights reserved.
|
||
|
||
This document is subject to BCP 78 and the IETF Trust's Legal
|
||
Provisions Relating to IETF Documents (https://trustee.ietf.org/
|
||
license-info) in effect on the date of publication of this document.
|
||
Please review these documents carefully, as they describe your rights
|
||
and restrictions with respect to this document. Code Components
|
||
extracted from this document must include Revised BSD License text as
|
||
described in Section 4.e of the Trust Legal Provisions and are
|
||
provided without warranty as described in the Revised BSD License.
|
||
|
||
Table of Contents
|
||
|
||
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
|
||
1.1. Problem Statement . . . . . . . . . . . . . . . . . . . . 5
|
||
1.2. Design Goals . . . . . . . . . . . . . . . . . . . . . . 5
|
||
1.3. Non-Goals . . . . . . . . . . . . . . . . . . . . . . . . 6
|
||
1.4. Relationship to Related Work . . . . . . . . . . . . . . 6
|
||
1.4.1. Concurrent Agent Authorization Proposals . . . . . . 7
|
||
1.5. Applicability . . . . . . . . . . . . . . . . . . . . . . 9
|
||
1.5.1. Model Context Protocol (MCP) Tool-Use Flows . . . . . 9
|
||
1.5.2. OpenAI Agents SDK and Function Calling . . . . . . . 9
|
||
1.5.3. LangGraph and LangChain Agent Graphs . . . . . . . . 10
|
||
1.5.4. Google Agent2Agent (A2A) Protocol . . . . . . . . . . 11
|
||
1.5.5. Enterprise Orchestration Without WIMSE (CrewAI,
|
||
AutoGen) . . . . . . . . . . . . . . . . . . . . . . 11
|
||
1.5.6. Relationship to WIMSE ECT . . . . . . . . . . . . . . 12
|
||
2. Conventions and Definitions . . . . . . . . . . . . . . . . . 12
|
||
3. ACT Lifecycle . . . . . . . . . . . . . . . . . . . . . . . . 13
|
||
3.1. Phase 1: Authorization Mandate . . . . . . . . . . . . . 13
|
||
3.2. Phase 2: Execution Record . . . . . . . . . . . . . . . . 14
|
||
3.3. Lifecycle State Machine . . . . . . . . . . . . . . . . . 14
|
||
4. ACT Token Format . . . . . . . . . . . . . . . . . . . . . . 15
|
||
4.1. JOSE Header . . . . . . . . . . . . . . . . . . . . . . . 15
|
||
4.2. JWT Claims: Authorization Phase . . . . . . . . . . . . . 16
|
||
4.2.1. Standard JWT Claims . . . . . . . . . . . . . . . . . 16
|
||
4.2.2. ACT Authorization Claims . . . . . . . . . . . . . . 16
|
||
4.3. JWT Claims: Execution Phase . . . . . . . . . . . . . . . 19
|
||
4.4. Complete Examples . . . . . . . . . . . . . . . . . . . . 21
|
||
4.4.1. Example: Phase 1 — Authorization Mandate . . . . . . 21
|
||
4.4.2. Example: Phase 2 — Execution Record (same token,
|
||
re-signed by target agent) . . . . . . . . . . . . . 22
|
||
5. Trust Model . . . . . . . . . . . . . . . . . . . . . . . . . 23
|
||
5.1. Tier 0: Bootstrap (TOFU — Trust On First Use) . . . . . . 23
|
||
5.2. Tier 1: Pre-Shared Keys (Mandatory-to-Implement) . . . . 23
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 2]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
5.3. Tier 2: PKI / X.509 . . . . . . . . . . . . . . . . . . . 24
|
||
5.4. Tier 3: Decentralized Identifiers (DID) . . . . . . . . . 24
|
||
5.5. Cross-Tier Interoperability . . . . . . . . . . . . . . . 25
|
||
6. Delegation Chain . . . . . . . . . . . . . . . . . . . . . . 25
|
||
6.1. Peer-to-Peer Delegation . . . . . . . . . . . . . . . . . 25
|
||
6.2. Privilege Reduction Requirements . . . . . . . . . . . . 25
|
||
6.3. Delegation Verification . . . . . . . . . . . . . . . . . 26
|
||
7. DAG Structure and Causal Ordering . . . . . . . . . . . . . . 26
|
||
7.1. DAG Validation . . . . . . . . . . . . . . . . . . . . . 27
|
||
7.2. Root Tasks and Fan-in . . . . . . . . . . . . . . . . . . 27
|
||
7.3. DAG vs Linear Delegation Chains . . . . . . . . . . . . . 27
|
||
7.3.1. What Linear Chains Express Well . . . . . . . . . . . 28
|
||
7.3.2. Limitations of Linear Chains . . . . . . . . . . . . 28
|
||
7.3.3. ACT's DAG Approach . . . . . . . . . . . . . . . . . 29
|
||
7.3.4. Verifiability Implications . . . . . . . . . . . . . 29
|
||
7.3.5. Interoperability with Linear-Chain Designs . . . . . 30
|
||
8. Verification Procedure . . . . . . . . . . . . . . . . . . . 30
|
||
8.1. Authorization Phase Verification . . . . . . . . . . . . 30
|
||
8.2. Execution Phase Verification . . . . . . . . . . . . . . 31
|
||
9. Transport . . . . . . . . . . . . . . . . . . . . . . . . . . 31
|
||
9.1. HTTP Header Transport . . . . . . . . . . . . . . . . . . 31
|
||
9.2. Non-HTTP Transports . . . . . . . . . . . . . . . . . . . 32
|
||
10. Audit Ledger Interface . . . . . . . . . . . . . . . . . . . 32
|
||
11. Security Considerations . . . . . . . . . . . . . . . . . . . 32
|
||
11.1. Threat Model . . . . . . . . . . . . . . . . . . . . . . 32
|
||
11.2. Self-Assertion Limitation . . . . . . . . . . . . . . . 33
|
||
11.3. Key Compromise . . . . . . . . . . . . . . . . . . . . . 33
|
||
11.4. Replay Attack Prevention . . . . . . . . . . . . . . . . 34
|
||
11.5. Equivocation . . . . . . . . . . . . . . . . . . . . . . 34
|
||
11.6. Privilege Escalation . . . . . . . . . . . . . . . . . . 35
|
||
11.7. Denial of Service . . . . . . . . . . . . . . . . . . . 35
|
||
12. Privacy Considerations . . . . . . . . . . . . . . . . . . . 35
|
||
13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 36
|
||
13.1. Media Type Registration . . . . . . . . . . . . . . . . 36
|
||
13.2. HTTP Header Field Registration . . . . . . . . . . . . . 36
|
||
13.3. JWT Claims Registration . . . . . . . . . . . . . . . . 37
|
||
14. References . . . . . . . . . . . . . . . . . . . . . . . . . 37
|
||
14.1. Normative References . . . . . . . . . . . . . . . . . . 37
|
||
14.2. Informative References . . . . . . . . . . . . . . . . . 38
|
||
Appendix A: Complete JSON Schema . . . . . . . . . . . . . . . . 41
|
||
Appendix B: Test Vectors . . . . . . . . . . . . . . . . . . . . 44
|
||
B.0. Key Material . . . . . . . . . . . . . . . . . . . . . . 44
|
||
B.1. Valid Phase 1 ACT: root mandate, Tier 1 (Ed25519), no
|
||
delegation . . . . . . . . . . . . . . . . . . . . . . . 45
|
||
B.2. Valid Phase 2 ACT: completed execution (transition from
|
||
B.1) . . . . . . . . . . . . . . . . . . . . . . . . . . 47
|
||
B.3. Valid Phase 2 ACT: fan-in with two predecessor tasks . . 49
|
||
B.4. Valid Phase 1 ACT: delegated mandate (depth 1) . . . . . 51
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 3]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
B.5. Valid Phase 2 ACT: delegated execution record . . . . . . 52
|
||
B.6. Invalid: delegation depth exceeds maximum . . . . . . . . 54
|
||
B.7. Invalid: capability escalation in delegated mandate . . . 56
|
||
B.8. Invalid: exec_act not present in cap . . . . . . . . . . 56
|
||
B.9. Invalid: DAG cycle (pred references own jti) . . . . . . 57
|
||
B.10. Invalid: missing predecessor task in DAG . . . . . . . . 58
|
||
B.11. Invalid: tampered payload . . . . . . . . . . . . . . . 59
|
||
B.12. Invalid: expired token . . . . . . . . . . . . . . . . . 61
|
||
B.13. Invalid: audience mismatch . . . . . . . . . . . . . . . 62
|
||
B.14. Invalid: Phase 2 record signed by wrong key . . . . . . 63
|
||
B.15. Invalid: unsigned token (alg "none") . . . . . . . . . . 65
|
||
Appendix C: Deployment Scenarios . . . . . . . . . . . . . . . . 65
|
||
C.1. Minimal Deployment (Zero Infrastructure) . . . . . . . . 65
|
||
C.2. Regulated Deployment with Hash-Chained Ledger . . . . . . 65
|
||
C.3. High-Assurance Cross-Organizational Deployment . . . . . 66
|
||
C.4. WIMSE Environment Integration . . . . . . . . . . . . . . 66
|
||
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 66
|
||
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 66
|
||
|
||
1. Introduction
|
||
|
||
Autonomous AI agents increasingly operate across organizational
|
||
boundaries, executing multi-step workflows where individual tasks are
|
||
delegated from one agent to another. These workflows create two
|
||
distinct, inseparable compliance requirements:
|
||
|
||
1. *Authorization*: was the agent permitted to perform the action,
|
||
under what constraints, and by whose authority?
|
||
|
||
2. *Accountability*: what did the agent actually do, with what
|
||
inputs, producing what outputs, in what causal relationship to
|
||
prior tasks?
|
||
|
||
Existing specifications address these requirements in isolation. The
|
||
Agent Authorization Profile (AAP) [I-D.aap-oauth-profile] provides
|
||
structured authorization via OAuth 2.0 but requires a central
|
||
Authorization Server. The WIMSE Execution Context Token
|
||
[I-D.nennemann-wimse-ect] provides execution accountability but
|
||
requires WIMSE workload identity infrastructure (SPIFFE/SPIRE).
|
||
|
||
This document defines the Agent Context Token (ACT), which addresses
|
||
both requirements in a single, self-contained token that requires no
|
||
shared infrastructure beyond the ability to verify asymmetric
|
||
signatures. The word "Context" in the name reflects what the token
|
||
carries: the complete invocation context of an agent — DAG
|
||
references, task metadata, capabilities, delegation chain, and
|
||
oversight claims — bound together in one cryptographically verifiable
|
||
envelope. ACT is positioned as the general agent context primitive,
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 4]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
with the WIMSE Execution Context Token (ECT)
|
||
[I-D.nennemann-wimse-ect] as a sibling profile specialized for
|
||
workload-identity-bound execution contexts in WIMSE deployments.
|
||
|
||
1.1. Problem Statement
|
||
|
||
Cross-organizational agent federation today faces a bootstrapping
|
||
problem: deploying shared OAuth infrastructure or a common SPIFFE
|
||
trust domain requires organizational agreement before the first
|
||
message is exchanged. In practice this means either:
|
||
|
||
(a) agents operate without cryptographic authorization or audit
|
||
trails, relying on application-layer access control only; or
|
||
|
||
(b) organizations adopt one party's identity infrastructure, creating
|
||
a hub-and-spoke dependency that contradicts the decentralized nature
|
||
of agent networks.
|
||
|
||
ACT solves this by making pre-shared keys the mandatory-to-implement
|
||
trust baseline — two agents can begin a secure, auditable interaction
|
||
with nothing more than an out-of-band key exchange — while providing
|
||
a clean upgrade path to PKI or DID-based trust without changing the
|
||
token format.
|
||
|
||
1.2. Design Goals
|
||
|
||
* *G1 — Zero infrastructure baseline*: ACT MUST be deployable with
|
||
no shared servers, no common identity provider, and no
|
||
transparency service.
|
||
|
||
* *G2 — Single token lifecycle*: Authorization and accountability
|
||
MUST be expressed in the same token format to prevent
|
||
authorization-accountability gaps.
|
||
|
||
* *G3 — Peer-to-peer delegation*: Delegation chains MUST be
|
||
verifiable without contacting an Authorization Server, using
|
||
cryptographic chaining of agent signatures.
|
||
|
||
* *G4 — DAG-native causal ordering*: Workflows with parallel
|
||
branches and fan-in dependencies MUST be expressible natively,
|
||
without flattening to a linear chain.
|
||
|
||
* *G5 — Cross-organizational interoperability*: ACTs issued by
|
||
agents in different trust domains MUST be verifiable by any
|
||
participant holding the issuing agent's public key.
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 5]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
* *G6 — Regulatory applicability*: ACT MUST provide sufficient
|
||
evidence for audit requirements in DORA [DORA], EU AI Act Article
|
||
12 [EUAIA], and IEC 62304 [IEC62304] without requiring additional
|
||
log formats.
|
||
|
||
* *G7 — Upgrade path*: The trust model MUST support migration from
|
||
pre-shared keys to PKI or DID without breaking existing ACT
|
||
chains.
|
||
|
||
1.3. Non-Goals
|
||
|
||
The following are explicitly out of scope:
|
||
|
||
* Defining internal AI model behavior or decision logic.
|
||
|
||
* Replacing organizational security policies or procedures.
|
||
|
||
* Defining storage formats for audit ledgers.
|
||
|
||
* Specifying token revocation infrastructure (deployments MAY use
|
||
existing mechanisms such as [RFC7009] for this purpose).
|
||
|
||
* Providing non-equivocation guarantees in standalone mode (see
|
||
Section 11.5 for the equivocation discussion and optional
|
||
transparency anchoring).
|
||
|
||
1.4. Relationship to Related Work
|
||
|
||
*AAP [I-D.aap-oauth-profile]*: ACT addresses the same authorization
|
||
problem as AAP but does not require an Authorization Server. ACT
|
||
delegation is peer-to-peer via cryptographic signature chaining; AAP
|
||
delegation requires OAuth Token Exchange [RFC8693] against a central
|
||
AS. ACT is not a profile of AAP; it is an infrastructure-independent
|
||
alternative for the same problem class.
|
||
|
||
*WIMSE ECT [I-D.nennemann-wimse-ect]*: ACT addresses the same
|
||
execution accountability problem as the WIMSE Execution Context Token
|
||
but does not require WIMSE workload identity infrastructure. ACT is
|
||
not a profile of WIMSE; it is deployable in environments without
|
||
SPIFFE/SPIRE. In environments where WIMSE is deployed, ACT MAY be
|
||
carried alongside WIMSE tokens to augment accountability with
|
||
authorization provenance.
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 6]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
*SCITT [I-D.ietf-scitt-architecture]*: For deployments requiring non-
|
||
equivocation guarantees (see Section 11.5), ACT execution records MAY
|
||
be anchored to a SCITT Transparency Service as a Layer 2 mechanism.
|
||
This is OPTIONAL and not required for basic ACT operation. Note: The
|
||
SCITT architecture draft is currently in AUTH48 (RFC Editor queue) at
|
||
version -22 and is about to become an RFC; readers should use the RFC
|
||
number once assigned.
|
||
|
||
1.4.1. Concurrent Agent Authorization Proposals
|
||
|
||
Several concurrent proposals in the IETF and academic communities
|
||
address overlapping portions of the agent authorization problem
|
||
space. This subsection situates ACT relative to those proposals.
|
||
Protocol-layer comparison of linear versus DAG delegation structure
|
||
is deferred to Section 7.3; the summaries below focus on scope and
|
||
deployability.
|
||
|
||
*AIP / IBCTs [AIP-IBCT]*: The Agent Interaction Protocol proposes
|
||
Interaction-Bound Capability Tokens in two modes: compact signed JWTs
|
||
for single-hop invocation and Biscuit/Datalog tokens for multi-hop
|
||
delegation, motivated by a survey of approximately 2,000 Model
|
||
Context Protocol servers that found no authorization enforcement.
|
||
ACT addresses the same problem class but relies exclusively on JWT/
|
||
JOSE throughout (no Biscuit or Datalog dependency), defines an
|
||
explicit two-phase lifecycle separating authorization (Mandate) from
|
||
proof-of-execution (Record), and supports DAG delegation structure.
|
||
IBCTs are modeled as append-only chains at the protocol layer; ACT
|
||
operates at the authorization graph layer with revocable lifecycle
|
||
states.
|
||
|
||
*SentinelAgent [SentinelAgent]*: SentinelAgent defines a formal
|
||
Delegation Chain Calculus with seven verifiable properties, a TLA+
|
||
mechanization, and reports 100% true-positive and 0% false-positive
|
||
rates against the DelegationBench v4 benchmark. It addresses the
|
||
same accountability question as ACT — namely, which principal
|
||
authorized a given chain of actions. The differentiator is
|
||
deployment substrate: SentinelAgent expresses its guarantees in a
|
||
domain-specific formal calculus, whereas ACT encodes the same
|
||
invariants in IETF-standard JWT infrastructure (RFC 7519, RFC 7515,
|
||
RFC 8032) already deployable in existing OAuth- and JOSE-aware
|
||
stacks.
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 7]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
*Agentic JWT [AgenticJWT]*: Agentic JWT derives a per-agent identity
|
||
as a one-way hash of the agent's prompt, registered tools, and
|
||
configuration, and chains delegation assertions across invocations.
|
||
It is the closest prior-art JWT-based construction for agentic
|
||
delegation. ACT differs in that it adds an explicit two-phase
|
||
lifecycle — separating the authorization mandate from the proof-of-
|
||
execution record — and expresses delegation as a DAG via the array-
|
||
valued pred claim rather than a strictly linear chain.
|
||
|
||
*OAuth Transaction Tokens for Agents
|
||
[I-D.oauth-transaction-tokens-for-agents]*: This draft extends OAuth
|
||
Transaction Tokens with an actchain claim (an ordered delegation
|
||
array), an agentic_ctx claim conveying intent and constraints, and
|
||
flow-type markers distinguishing interactive from autonomous
|
||
invocations. It is complementary to ACT at the OAuth layer. The
|
||
primary differentiators are topology and infrastructure dependency:
|
||
Transaction Tokens for Agents presume an OAuth Authorization Server
|
||
and use a linear actchain, whereas ACT operates peer-to-peer without
|
||
any AS and uses a DAG-valued pred. A detailed differencing document
|
||
is referenced in Section 11.
|
||
|
||
*Helixar Delegation Protocol (HDP)
|
||
[I-D.helixar-hdp-agentic-delegation]*: HDP specifies Ed25519
|
||
signatures over RFC 8785-canonicalized JSON, an append-only linear
|
||
delegation chain with session binding, and offline verification. ACT
|
||
addresses the same problem but is encoded in JWT/JOSE (aligning with
|
||
the broader IETF token ecosystem) rather than raw canonical JSON, and
|
||
its pred claim admits DAG topologies rather than strictly linear
|
||
chains.
|
||
|
||
*SCITT Profile for AI Agent Execution Records
|
||
[I-D.emirdag-scitt-ai-agent-execution]*: This draft defines a SCITT
|
||
profile in which AgentInteractionRecord (AIR) payloads are carried as
|
||
COSE_Sign1 statements anchored to a SCITT Transparency Service. It
|
||
is highly complementary to ACT: where ACT defines the two-phase
|
||
lifecycle token issued and consumed by agents at runtime, the SCITT
|
||
AI Agent Execution draft defines the payload format suitable for
|
||
long-term anchoring. Implementations that anchor Phase 2 ACTs to
|
||
SCITT (Section 11) SHOULD consider the AIR payload structure defined
|
||
in that draft as the canonical encoding for anchored records.
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 8]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
1.5. Applicability
|
||
|
||
ACT is designed as a general-purpose primitive for AI agent
|
||
authorization and execution accountability. While a sibling
|
||
specification [I-D.nennemann-wimse-ect] profiles execution context
|
||
tokens specifically for the WIMSE working group's workload identity
|
||
infrastructure, ACT operates without any shared identity plane. This
|
||
section identifies deployment contexts where ACT applies
|
||
independently of WIMSE, and clarifies how ACT complements — rather
|
||
than competes with — ecosystem-specific agent protocols.
|
||
|
||
1.5.1. Model Context Protocol (MCP) Tool-Use Flows
|
||
|
||
The Model Context Protocol [MCP-SPEC] defines a client-server
|
||
interface by which LLM hosts invoke external tools via structured
|
||
JSON-RPC calls. MCP 2025-11-25 mandates OAuth 2.1 for transport-
|
||
layer authentication, but provides no mechanism for carrying per-
|
||
invocation authorization constraints or for producing a tamper-
|
||
evident record of what arguments were passed and what result was
|
||
returned.
|
||
|
||
ACT addresses this gap as follows: when an MCP host is about to
|
||
dispatch a tool call on behalf of an agent, it SHOULD issue a Phase 1
|
||
ACT Mandate encoding the permitted tool name (e.g., as a capability
|
||
constraint), the declaring scope, and any parameter-level constraints
|
||
applicable to that invocation. The MCP server, upon receiving the
|
||
request, MAY validate the ACT Mandate and, upon completing the tool
|
||
execution, SHOULD transition the token to Phase 2 by appending
|
||
SHA-256 hashes of the serialized input arguments and the JSON
|
||
response, then re-sign. The resulting Phase 2 ACT constitutes an
|
||
unforgeable record that a specific tool was called with specific
|
||
arguments and returned a specific result, independently of MCP's
|
||
OAuth layer.
|
||
|
||
This integration requires no modification to MCP transport; the ACT
|
||
SHOULD be carried in the ACT-Mandate and ACT-Record HTTP headers
|
||
defined in Section 9.1 of this document.
|
||
|
||
1.5.2. OpenAI Agents SDK and Function Calling
|
||
|
||
The OpenAI Agents SDK [OPENAI-AGENTS-SDK] enables composition of
|
||
agents via handoffs — structured transfers of control from one agent
|
||
to another, each potentially invoking registered function tools. The
|
||
SDK provides no built-in mechanism for a receiving agent to verify
|
||
that the handoff was authorized by a named principal, nor for the
|
||
invoking agent to produce a verifiable record of what functions it
|
||
called.
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 9]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
ACT is applicable at the handoff boundary: the orchestrating agent
|
||
SHOULD issue a Phase 1 ACT Mandate to the receiving agent at the
|
||
moment of handoff, encoding the permitted function set as capability
|
||
constraints and the maximum privilege the receiving agent MAY
|
||
exercise. The receiving agent SHOULD attach its Phase 2 ACT Record
|
||
to any callback or downstream response, providing the orchestrator
|
||
with cryptographic evidence of the actions taken. In multi-turn
|
||
chains involving multiple handoffs, the DAG linkage (Section 7)
|
||
allows each handoff to be expressed as a parent-child edge,
|
||
preserving the full causal ordering of the agent invocation sequence.
|
||
|
||
Implementations that use the OpenAI function calling API directly,
|
||
without the Agents SDK, MAY apply ACT at the application layer: the
|
||
calling process issues a Phase 1 ACT before the function call
|
||
parameter block is finalized, and the receiving function handler
|
||
returns a Phase 2 ACT alongside its JSON result.
|
||
|
||
1.5.3. LangGraph and LangChain Agent Graphs
|
||
|
||
LangGraph [LANGGRAPH] models agent workflows as typed StateGraphs in
|
||
which nodes represent agent invocations or tool calls and edges
|
||
represent conditional transitions. The DAG structure of ACT
|
||
(Section 7) is a natural fit for this model: each LangGraph node that
|
||
performs an observable action corresponds to exactly one ACT task
|
||
identifier (tid), and directed edges in the LangGraph correspond to
|
||
pred (predecessor) references in successor ACTs.
|
||
|
||
ACT is applicable at the node boundary: when a LangGraph node
|
||
dispatches a sub-agent or invokes a tool with side effects, it SHOULD
|
||
issue a Phase 1 ACT Mandate encoding the node's permitted actions
|
||
before any external call is made. Upon transition out of the node, a
|
||
Phase 2 ACT Record SHOULD be produced and attached to the LangGraph
|
||
state object alongside the node's output. Downstream nodes that fan-
|
||
in from multiple predecessors MAY retrieve the set of parent ACT
|
||
identifiers from the shared state to populate their pred array,
|
||
thereby expressing LangGraph's fan-in semantics within the ACT DAG
|
||
without any additional infrastructure.
|
||
|
||
In contrast to LangGraph's built-in state audit trail, which is
|
||
mutable in-process memory, Phase 2 ACTs are cryptographically signed
|
||
and portable: they can be exported from a LangGraph run and submitted
|
||
to an external audit ledger, satisfying compliance requirements that
|
||
cannot be met by in-process logging alone.
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 10]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
1.5.4. Google Agent2Agent (A2A) Protocol
|
||
|
||
The Agent2Agent protocol [A2A-SPEC] defines a task-oriented JSON-RPC
|
||
interface for inter-agent communication, with authentication
|
||
delegated to OAuth 2.0 or API key schemes declared in each agent's
|
||
Agent Card. A2A provides no mechanism for a receiving agent to
|
||
verify the authorization provenance of a task request beyond the
|
||
transport-layer credential, and produces no token that represents the
|
||
execution of the task in a verifiable, portable form.
|
||
|
||
ACT is applicable as a session-layer accountability complement to
|
||
A2A: a client agent SHOULD include a Phase 1 ACT Mandate in the
|
||
metadata field of the A2A Task object, encoding the task type as a
|
||
capability constraint and the delegating agent's identity as the ACT
|
||
issuer. The receiving agent SHOULD validate the Mandate before
|
||
beginning task execution and SHOULD return a Phase 2 ACT Record as an
|
||
artifact in the A2A TaskResult, enabling the client agent to retain
|
||
cryptographic proof of what was executed on its behalf.
|
||
|
||
This integration does not require modification to A2A's transport or
|
||
authentication scheme; ACT and A2A's OAuth credentials operate at
|
||
independent layers and are not redundant. A2A's credential answers
|
||
"is this client permitted to contact this server?"; the ACT Mandate
|
||
answers "is this agent permitted to request this specific task under
|
||
these constraints?".
|
||
|
||
1.5.5. Enterprise Orchestration Without WIMSE (CrewAI, AutoGen)
|
||
|
||
Enterprise orchestration frameworks such as CrewAI [CREWAI] and
|
||
AutoGen [AUTOGEN] deploy multi-agent systems within a single
|
||
organizational boundary, typically without SPIFFE/SPIRE workload
|
||
identity infrastructure. In these environments, OAuth Authorization
|
||
Servers are often unavailable or impractical to deploy for intra-
|
||
process agent communication.
|
||
|
||
ACT is applicable in this context via its Tier 1 (pre-shared key)
|
||
trust model (Section 5.2): each agent role in a CrewAI Crew or
|
||
AutoGen ConversableAgent graph is assigned an Ed25519 keypair at
|
||
instantiation time. The orchestrating agent issues Phase 1 Mandates
|
||
to worker agents before delegating tasks, constraining each worker to
|
||
only the tools and actions relevant to its role. Worker agents
|
||
produce Phase 2 Records on task completion. The resulting ACT chain
|
||
is exportable as a structured audit trail that satisfies the per-
|
||
action logging requirements of DORA [DORA] and EU AI Act Article 12
|
||
[EUAIA] without requiring shared infrastructure beyond the ability to
|
||
exchange public keys at deployment time.
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 11]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
Implementations SHOULD NOT use ACT's self-assertion mode (where an
|
||
agent issues and records its own mandate without external sign-off)
|
||
in regulated workflows; at minimum, the orchestrating agent MUST sign
|
||
the initial Mandate so that accountability is anchored to a principal
|
||
outside the executing agent.
|
||
|
||
1.5.6. Relationship to WIMSE ECT
|
||
|
||
Where WIMSE infrastructure is deployed, ACT and the WIMSE Execution
|
||
Context Token [I-D.nennemann-wimse-ect] serve complementary and non-
|
||
overlapping functions. The ECT records workload-level execution in
|
||
WIMSE terms — which SPIFFE workload executed, in which trust domain,
|
||
against which service. ACT records the authorization provenance —
|
||
which agent was permitted to request which action, under what
|
||
capability constraints, by whose authority — and transitions that
|
||
authorization record into an execution record upon task completion.
|
||
|
||
In mixed environments, both tokens SHOULD be carried simultaneously:
|
||
the Workload-Identity header carries the WIMSE ECT; the ACT-Record
|
||
header carries the ACT. Verifiers MAY correlate the two by matching
|
||
the ACT tid claim against application-layer identifiers present in
|
||
the ECT's task context. Neither token is a profile or extension of
|
||
the other; they operate at different abstraction layers and their co-
|
||
presence is additive.
|
||
|
||
2. Conventions and Definitions
|
||
|
||
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
|
||
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
|
||
"OPTIONAL" in this document are to be interpreted as described in
|
||
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
|
||
capitals, as shown here.
|
||
|
||
*Agent*: An autonomous software entity that executes tasks, issues
|
||
ACTs as mandates for sub-agents, and produces ACTs as execution
|
||
records of its own actions.
|
||
|
||
*Authorization Mandate*: An ACT in Phase 1, encoding what an agent is
|
||
permitted to do, under what constraints, and by whose authority.
|
||
|
||
*Execution Record*: An ACT in Phase 2, encoding what an agent
|
||
actually did, including cryptographic hashes of inputs and outputs
|
||
and causal links to predecessor tasks.
|
||
|
||
*Directed Acyclic Graph (DAG)*: A graph structure representing task
|
||
dependency ordering where edges are directed and no cycles exist.
|
||
Used by ACT to model causal relationships between tasks in a
|
||
workflow.
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 12]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
*Delegation Chain*: A cryptographically verifiable sequence of ACT
|
||
issuances from a root authority through one or more agents, each
|
||
signing a new ACT that reduces privileges relative to the one it
|
||
received.
|
||
|
||
*Trust Tier*: A level of key management infrastructure used to
|
||
establish the public key of an ACT issuer. Tiers range from pre-
|
||
shared keys (Tier 1, mandatory) to PKI (Tier 2) and DIDs (Tier 3).
|
||
|
||
*Workflow*: A set of related tasks, identified by a shared wid claim,
|
||
forming a single logical unit of work.
|
||
|
||
3. ACT Lifecycle
|
||
|
||
An ACT has a two-phase lifecycle. The same token format is used in
|
||
both phases; the presence or absence of execution claims determines
|
||
which phase a token represents.
|
||
|
||
A token is a *Phase 2 Execution Record* if and only if the claim
|
||
exec_act is present. A token that does not contain exec_act is a
|
||
*Phase 1 Authorization Mandate*. Verifiers MUST determine the phase
|
||
before applying verification rules, and MUST reject a token that is
|
||
presented in the wrong phase for the operation being performed.
|
||
|
||
3.1. Phase 1: Authorization Mandate
|
||
|
||
In Phase 1, an ACT is created by a delegating agent (or a human
|
||
operator) to authorize a target agent to perform a specific task.
|
||
The token carries:
|
||
|
||
* The identity of the issuing agent and the target agent.
|
||
|
||
* The capabilities granted, with associated constraints.
|
||
|
||
* Human oversight requirements for high-impact actions.
|
||
|
||
* The delegation provenance (who authorized the issuer to delegate).
|
||
|
||
* A task identifier and declared purpose.
|
||
|
||
The Phase 1 ACT is signed by the issuing agent using its private key.
|
||
The target agent receives the ACT and uses it as a bearer mandate —
|
||
evidence that it is authorized to proceed.
|
||
|
||
Phase 1 ACTs are short-lived. Implementations SHOULD set expiration
|
||
(exp) to no more than 15 minutes after issuance (iat) for automated
|
||
agent-to-agent workflows. Longer lifetimes MAY be used for human-
|
||
initiated mandates where the agent may not act immediately.
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 13]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
3.2. Phase 2: Execution Record
|
||
|
||
Upon completing the authorized task, the executing agent MUST
|
||
transition the ACT to Phase 2 by:
|
||
|
||
1. Adding the exec_act claim describing the action performed.
|
||
|
||
2. Optionally adding inp_hash and/or out_hash SHA-256 hashes of task
|
||
inputs and outputs (RECOMMENDED for regulated environments).
|
||
|
||
3. Adding the pred array referencing predecessor task identifiers
|
||
(DAG dependencies).
|
||
|
||
4. Adding exec_ts and status claims.
|
||
|
||
5. Re-signing the complete token with its own private key.
|
||
|
||
The re-signing is critical: it produces a new signature over the
|
||
combined authorization + execution claims, binding the executing
|
||
agent's cryptographic identity to both the mandate it received and
|
||
the execution it performed. This creates a single, non-repudiable
|
||
record that answers both "was this agent authorized?" and "what did
|
||
it do?"
|
||
|
||
Note on issuer signature preservation: re-signing replaces the Phase
|
||
1 signature produced by the issuing agent (iss). The integrity of
|
||
the original mandate is preserved through the del.chain mechanism:
|
||
the chain entry's sig field is the iss agent's signature over the
|
||
Phase 1 ACT, and this signature remains intact and verifiable in the
|
||
Phase 2 token. For root mandates where del.chain is empty, the
|
||
issuer's signature is not independently preserved in Phase 2.
|
||
Deployments requiring independent verifiability of the original
|
||
mandate SHOULD retain the Phase 1 ACT separately alongside the Phase
|
||
2 record.
|
||
|
||
The resulting Phase 2 ACT SHOULD be submitted to an audit ledger
|
||
(Section 10) and MAY be sent to the next agent in the workflow as
|
||
evidence of completed prerequisites.
|
||
|
||
3.3. Lifecycle State Machine
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 14]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
[Issuer creates Phase 1 ACT]
|
||
|
|
||
| sign(issuer_key)
|
||
v
|
||
+------------------+
|
||
| MANDATE | Phase 1: Authorization Mandate
|
||
| (unsigned by | Carried as bearer token by target agent
|
||
| target agent) |
|
||
+------------------+
|
||
|
|
||
| Target agent executes task
|
||
| adds exec_act, inp_hash, out_hash, pred
|
||
| re-signs with target_agent_key
|
||
v
|
||
+------------------+
|
||
| RECORD | Phase 2: Execution Record
|
||
| (signed by | Submitted to ledger, passed to next agent
|
||
| target agent) |
|
||
+------------------+
|
||
|
|
||
| (optional) anchor to SCITT Transparency Service
|
||
v
|
||
+------------------+
|
||
| ANCHORED | Phase 2 + external non-equivocation
|
||
+------------------+
|
||
|
||
4. ACT Token Format
|
||
|
||
An ACT is a JSON Web Token [RFC7519] signed as a JSON Web Signature
|
||
[RFC7515] using JWS Compact Serialization. All ACTs MUST use JWS
|
||
Compact Serialization to ensure they can be carried in a single HTTP
|
||
header value.
|
||
|
||
4.1. JOSE Header
|
||
|
||
The ACT JOSE header MUST contain:
|
||
|
||
{
|
||
"alg": "ES256",
|
||
"typ": "act+jwt",
|
||
"kid": "agent-a-key-2026-03"
|
||
}
|
||
|
||
*alg* (REQUIRED): The digital signature algorithm. Implementations
|
||
MUST support ES256 [RFC7518]. EdDSA (Ed25519) [RFC8037] is
|
||
RECOMMENDED for new deployments due to smaller signatures and
|
||
resistance to side-channel attacks. Symmetric algorithms (HS256,
|
||
HS384, HS512) MUST NOT be used. The "alg" value MUST NOT be "none".
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 15]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
*typ* (REQUIRED): MUST be "act+jwt" to distinguish ACTs from other
|
||
JWT types.
|
||
|
||
*kid* (REQUIRED): An identifier for the signing key. In Tier 1
|
||
deployments (pre-shared keys), this is an opaque string agreed out-
|
||
of-band. In Tier 2 deployments (PKI), this is the X.509 certificate
|
||
thumbprint. In Tier 3 deployments (DID), this is the DID key
|
||
fragment (e.g., did:key:z6Mk...#key-1).
|
||
|
||
*x5c* (OPTIONAL): In Tier 2 deployments, the X.509 certificate chain
|
||
MAY be included to enable verification without out-of-band key
|
||
distribution.
|
||
|
||
*did* (OPTIONAL): In Tier 3 deployments, the full DID of the issuing
|
||
agent MAY be included for resolution.
|
||
|
||
4.2. JWT Claims: Authorization Phase
|
||
|
||
4.2.1. Standard JWT Claims
|
||
|
||
*iss* (REQUIRED): The identifier of the agent issuing the mandate.
|
||
Format depends on trust tier: an opaque string (Tier 1), an X.509
|
||
Subject DN (Tier 2), or a DID (Tier 3).
|
||
|
||
*sub* (REQUIRED): The identifier of the agent authorized to act.
|
||
MUST use the same format convention as iss.
|
||
|
||
*aud* (REQUIRED): The intended recipient(s). MUST include the
|
||
identifier of the target agent (sub). When an audit ledger is
|
||
deployed, MUST also include the ledger's identifier. When multiple
|
||
recipients are present, MUST be an array. Verifiers that are audit
|
||
ledgers MUST verify that their own identifier appears in aud.
|
||
|
||
*iat* (REQUIRED): Issuance time as a NumericDate [RFC7519].
|
||
|
||
*exp* (REQUIRED): Expiration time. Implementations SHOULD set to no
|
||
more than 15 minutes after iat for automated workflows.
|
||
|
||
*jti* (REQUIRED): A UUID [RFC9562] uniquely identifying this ACT and,
|
||
in Phase 2, the task it records. Used as the task identifier for DAG
|
||
predecessor references in pred.
|
||
|
||
4.2.2. ACT Authorization Claims
|
||
|
||
*wid* (OPTIONAL): A UUID identifying the workflow to which this task
|
||
belongs. When present, groups related ACTs and scopes jti uniqueness
|
||
to the workflow.
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 16]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
*task* (REQUIRED): An object describing the authorized task:
|
||
|
||
{
|
||
"task": {
|
||
"purpose": "validate_patient_dosage",
|
||
"data_sensitivity": "restricted",
|
||
"created_by": "operator:clinical-admin-01",
|
||
"expires_at": 1772064750
|
||
}
|
||
}
|
||
|
||
* purpose (REQUIRED): A string describing the intended task.
|
||
Implementations SHOULD use a controlled vocabulary or reverse-
|
||
domain notation (e.g., "com.example.validate_dosage") to enable
|
||
semantic consistency checking by the receiving agent.
|
||
|
||
* data_sensitivity (OPTIONAL): One of "public", "internal",
|
||
"confidential", "restricted". Receiving agents MUST NOT perform
|
||
actions that would expose data above this classification.
|
||
|
||
* created_by (OPTIONAL): An identifier for the human or system that
|
||
initiated the workflow. SHOULD be pseudonymous (see Section 12).
|
||
|
||
* expires_at (OPTIONAL): A NumericDate after which the task mandate
|
||
is no longer valid, independent of exp.
|
||
|
||
*cap* (REQUIRED): An array of capability objects, each specifying an
|
||
action the agent is authorized to perform and the constraints under
|
||
which it may do so:
|
||
|
||
{
|
||
"cap": [
|
||
{
|
||
"action": "read.patient_record",
|
||
"constraints": {
|
||
"patient_id_scope": "current_task_only",
|
||
"max_records": 1,
|
||
"data_classification_max": "restricted"
|
||
}
|
||
},
|
||
{
|
||
"action": "write.dosage_recommendation",
|
||
"constraints": {
|
||
"status": "draft_only"
|
||
}
|
||
}
|
||
]
|
||
}
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 17]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
Action names MUST conform to the ABNF grammar:
|
||
|
||
action-name = component *( "." component )
|
||
component = ALPHA *( ALPHA / DIGIT / "-" / "_" )
|
||
|
||
Receiving agents MUST perform exact string matching on action names.
|
||
Wildcard matching is NOT part of this specification.
|
||
|
||
When multiple capabilities match the same action, OR semantics apply:
|
||
if ANY capability grants the action, the request is authorized
|
||
subject to that capability's constraints. When multiple constraints
|
||
exist within a single capability, AND semantics apply: ALL
|
||
constraints MUST be satisfied. When the same constraint key appears
|
||
in both a capability-level and a policy-level context, the more
|
||
restrictive value applies: lower numeric limits, narrower allow-lists
|
||
(intersection), broader block-lists (union), and narrower time
|
||
windows.
|
||
|
||
*oversight* (OPTIONAL): Human oversight requirements:
|
||
|
||
{
|
||
"oversight": {
|
||
"requires_approval_for": ["write.publish", "execute.payment"],
|
||
"approval_ref": "https://approval.example.com/workflow/w-123"
|
||
}
|
||
}
|
||
|
||
When requires_approval_for lists an action, the receiving agent MUST
|
||
NOT execute that action autonomously. The approval mechanism is out
|
||
of scope for this specification.
|
||
|
||
*del* (OPTIONAL): Delegation provenance, establishing the chain of
|
||
authority from the root mandate to this ACT. If del is absent, the
|
||
ACT MUST be treated as a root mandate with depth = 0 and further
|
||
delegation is not permitted (i.e., the receiving agent MUST NOT issue
|
||
sub-mandates based on this ACT).
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 18]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"del": {
|
||
"depth": 1,
|
||
"max_depth": 3,
|
||
"chain": [
|
||
{
|
||
"delegator": "did:key:z6MkhaXgBZDvotDkL5257faiztiGiC2QtKLGpbnnEGta2doK",
|
||
"jti": "550e8400-e29b-41d4-a716-446655440000",
|
||
"sig": "base64url-encoded-signature-of-parent-act-hash"
|
||
}
|
||
]
|
||
}
|
||
}
|
||
|
||
* depth: The current delegation depth. 0 means this is a root
|
||
mandate issued by a human or root authority.
|
||
|
||
* max_depth: The maximum permitted delegation depth. Receiving
|
||
agents MUST NOT issue sub-mandates that would exceed this depth.
|
||
|
||
* chain: An array of delegation provenance records ordered from root
|
||
to immediate parent (chain[0] is the root authority, chain[depth-
|
||
1] is the direct parent of this ACT). Each entry contains:
|
||
|
||
- delegator: The identifier of the agent that authorized this
|
||
delegation step (i.e., the iss of the parent ACT at that
|
||
depth).
|
||
|
||
- jti: The jti of the parent ACT that authorized this delegation
|
||
step.
|
||
|
||
- sig: The delegating agent's signature over the SHA-256 hash of
|
||
that parent ACT, providing cryptographic linkage without
|
||
requiring the full parent ACT to be transmitted.
|
||
|
||
The sig field in each chain entry is the critical departure from
|
||
AAP's delegation model: rather than requiring a central AS to
|
||
validate the chain, any verifier holding the delegating agent's
|
||
public key can independently verify each step by recomputing the hash
|
||
and checking the signature.
|
||
|
||
4.3. JWT Claims: Execution Phase
|
||
|
||
The following claims are added by the executing agent when
|
||
transitioning to Phase 2. Their presence distinguishes an Execution
|
||
Record from an Authorization Mandate.
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 19]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
*exec_act* (REQUIRED in Phase 2): A string identifying the action
|
||
actually performed. MUST conform to the same ABNF grammar as
|
||
capability action names. MUST match one of the action values in the
|
||
cap array of the Phase 1 claims.
|
||
|
||
*pred* (REQUIRED in Phase 2): An array of jti values of predecessor
|
||
tasks in the DAG. An empty array indicates a root task. Each value
|
||
MUST be the jti of a previously verified ACT (Phase 2) within the
|
||
same workflow (same wid) or the global ACT store if wid is absent.
|
||
|
||
*inp_hash* (OPTIONAL): The base64url encoding (without padding) of
|
||
the SHA-256 hash of the task's input data, computed over the raw
|
||
octets of the serialized input. Provides cryptographic evidence of
|
||
what data the agent processed.
|
||
|
||
*out_hash* (OPTIONAL): The base64url encoding (without padding) of
|
||
the SHA-256 hash of the task's output data, using the same format as
|
||
inp_hash. Provides cryptographic evidence of what data the agent
|
||
produced.
|
||
|
||
*exec_ts* (REQUIRED in Phase 2): A NumericDate recording the actual
|
||
time of task execution. MAY differ from iat when the agent queued
|
||
the mandate before execution. MUST be greater than or equal to iat.
|
||
SHOULD be less than or equal to exp; execution after mandate expiry
|
||
is possible when tasks are long-running and MUST NOT cause automatic
|
||
rejection, but implementors SHOULD log a warning.
|
||
|
||
*status* (REQUIRED in Phase 2): One of "completed", "failed",
|
||
"partial". Allows audit systems to distinguish successful execution
|
||
from partial or failed attempts, which is essential for regulated
|
||
environments where failed attempts must be recorded.
|
||
|
||
*err* (OPTIONAL, present when status is "failed" or "partial"): An
|
||
object providing error context:
|
||
|
||
{
|
||
"err": {
|
||
"code": "constraint_violation",
|
||
"detail": "data_classification_max exceeded"
|
||
}
|
||
}
|
||
|
||
Error detail SHOULD NOT reveal internal system state beyond what is
|
||
necessary for audit purposes.
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 20]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
4.4. Complete Examples
|
||
|
||
4.4.1. Example: Phase 1 — Authorization Mandate
|
||
|
||
{
|
||
"alg": "ES256",
|
||
"typ": "act+jwt",
|
||
"kid": "agent-clinical-key-2026-03"
|
||
}
|
||
.
|
||
{
|
||
"iss": "did:key:z6MkhaXgBZDvotDkL5257faiztiGiC2QtKLGpbnnEGta2doK",
|
||
"sub": "did:key:z6MknGc3omCyas4b1GmEn4xySHgLuSHxrKrUBnrhJekxZHFz",
|
||
"aud": [
|
||
"did:key:z6MknGc3omCyas4b1GmEn4xySHgLuSHxrKrUBnrhJekxZHFz",
|
||
"https://ledger.hospital.example.com"
|
||
],
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440001",
|
||
|
||
"wid": "a0b1c2d3-e4f5-6789-abcd-ef0123456789",
|
||
|
||
"task": {
|
||
"purpose": "validate_treatment_recommendation",
|
||
"data_sensitivity": "restricted",
|
||
"created_by": "operator:clinical-admin-01"
|
||
},
|
||
|
||
"cap": [
|
||
{
|
||
"action": "read.patient_record",
|
||
"constraints": {
|
||
"patient_id_scope": "current_task_only",
|
||
"max_records": 1
|
||
}
|
||
},
|
||
{
|
||
"action": "write.safety_assessment",
|
||
"constraints": {
|
||
"status": "draft_only"
|
||
}
|
||
}
|
||
],
|
||
|
||
"oversight": {
|
||
"requires_approval_for": ["write.publish_assessment"]
|
||
},
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 21]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
"del": {
|
||
"depth": 0,
|
||
"max_depth": 2,
|
||
"chain": []
|
||
}
|
||
}
|
||
|
||
4.4.2. Example: Phase 2 — Execution Record (same token, re-signed by
|
||
target agent)
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "agent-safety-key-2026-03"
|
||
}
|
||
.
|
||
{
|
||
"iss": "did:key:z6MkhaXgBZDvotDkL5257faiztiGiC2QtKLGpbnnEGta2doK",
|
||
"sub": "did:key:z6MknGc3omCyas4b1GmEn4xySHgLuSHxrKrUBnrhJekxZHFz",
|
||
"aud": [
|
||
"did:key:z6MknGc3omCyas4b1GmEn4xySHgLuSHxrKrUBnrhJekxZHFz",
|
||
"https://ledger.hospital.example.com"
|
||
],
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440001",
|
||
|
||
"wid": "a0b1c2d3-e4f5-6789-abcd-ef0123456789",
|
||
|
||
"task": {
|
||
"purpose": "validate_treatment_recommendation",
|
||
"data_sensitivity": "restricted",
|
||
"created_by": "operator:clinical-admin-01"
|
||
},
|
||
|
||
"cap": [
|
||
{
|
||
"action": "read.patient_record",
|
||
"constraints": {
|
||
"patient_id_scope": "current_task_only",
|
||
"max_records": 1
|
||
}
|
||
},
|
||
{
|
||
"action": "write.safety_assessment",
|
||
"constraints": {
|
||
"status": "draft_only"
|
||
}
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 22]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
}
|
||
],
|
||
|
||
"oversight": {
|
||
"requires_approval_for": ["write.publish_assessment"]
|
||
},
|
||
|
||
"del": {
|
||
"depth": 0,
|
||
"max_depth": 2,
|
||
"chain": []
|
||
},
|
||
|
||
"exec_act": "write.safety_assessment",
|
||
"pred": ["550e8400-e29b-41d4-a716-446655440000"],
|
||
"inp_hash": "n4bQgYhMfWWaL-qgxVrQFaO_TxsrC4Is0V1sFbDwCgg",
|
||
"out_hash": "LCa0a2j_xo_5m0U8HTBBNBNCLXBkg7-g-YpeiGJm564",
|
||
"exec_ts": 1772064300,
|
||
"status": "completed"
|
||
}
|
||
|
||
5. Trust Model
|
||
|
||
ACT defines four trust tiers. Tier 1 is mandatory-to-implement; all
|
||
others are optional upgrades. An ACT verifier MUST be able to
|
||
process ACTs from any tier it has configured. The trust tier in use
|
||
is determined by the kid format and the presence of x5c or did header
|
||
parameters.
|
||
|
||
5.1. Tier 0: Bootstrap (TOFU — Trust On First Use)
|
||
|
||
Tier 0 is NOT part of the normative trust model and MUST NOT be used
|
||
in regulated environments. It is defined here for documentation
|
||
purposes only, to describe the common bootstrapping scenario.
|
||
|
||
In Tier 0, the first ACT received from an agent establishes its
|
||
public key. This is equivalent to SSH TOFU behavior: an attacker who
|
||
intercepts the first message can substitute their own key. Tier 0
|
||
deployments MUST transition to Tier 1 or higher before exchanging
|
||
ACTs that carry sensitive capabilities.
|
||
|
||
5.2. Tier 1: Pre-Shared Keys (Mandatory-to-Implement)
|
||
|
||
In Tier 1, both parties exchange public keys out-of-band prior to the
|
||
first ACT exchange. The kid is an opaque string agreed during the
|
||
key exchange. Implementations MUST support Tier 1.
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 23]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
Key exchange MAY occur via any out-of-band mechanism: manual
|
||
configuration, a configuration management system, or a prior
|
||
authenticated channel. This specification does not mandate a
|
||
specific key exchange protocol.
|
||
|
||
Tier 1 public keys MUST be Ed25519 [RFC8037] or P-256 (ES256)
|
||
[RFC7518] keys. RSA keys SHOULD NOT be used in Tier 1 deployments
|
||
due to key size. Key rotation MUST be performed out-of-band using
|
||
the same mechanism as the initial exchange.
|
||
|
||
5.3. Tier 2: PKI / X.509
|
||
|
||
In Tier 2, agent identity is bound to an X.509 certificate issued by
|
||
a mutually trusted Certificate Authority (CA). The kid is the
|
||
certificate thumbprint (SHA-256 of the DER-encoded certificate).
|
||
|
||
Cross-organizational ACT exchange in Tier 2 requires either:
|
||
|
||
(a) a mutually trusted root CA, or (b) cross-certification between
|
||
the organizations' CAs, or (c) explicit trust anchoring (one
|
||
organization's CA is added to the other's trust store).
|
||
|
||
The x5c JOSE header parameter [RFC7515] MAY carry the full
|
||
certificate chain to enable verification without out-of-band trust
|
||
store configuration.
|
||
|
||
5.4. Tier 3: Decentralized Identifiers (DID)
|
||
|
||
In Tier 3, agent identity is expressed as a DID [W3C-DID]. The kid
|
||
is a DID key fragment. The did JOSE header parameter carries the
|
||
full DID for resolution.
|
||
|
||
Implementations SHOULD support at minimum did:key [DID-KEY] for self-
|
||
contained key distribution without external resolution, and did:web
|
||
[DID-WEB] for organizations that prefer DNS-anchored identity.
|
||
|
||
DID resolution latency introduces a dependency on external
|
||
infrastructure. To preserve the zero-infrastructure baseline,
|
||
implementations using Tier 3 MAY cache DID Documents and MUST specify
|
||
a maximum cache TTL in their configuration.
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 24]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
5.5. Cross-Tier Interoperability
|
||
|
||
A delegation chain MAY include agents operating at different trust
|
||
tiers. Each step in the chain is verified using the trust tier of
|
||
the signing agent at that step. Verifiers MUST NOT reject a chain
|
||
solely because it mixes trust tiers, but MAY apply stricter policy
|
||
for chains that include Tier 0 or Tier 1 steps when exchanging
|
||
sensitive capabilities.
|
||
|
||
6. Delegation Chain
|
||
|
||
ACT delegation is peer-to-peer: no Authorization Server is involved.
|
||
Delegation is expressed as a cryptographically verifiable chain of
|
||
ACT issuances, where each step reduces privileges relative to the
|
||
previous step.
|
||
|
||
6.1. Peer-to-Peer Delegation
|
||
|
||
When Agent A authorizes Agent B to perform a sub-task, Agent A:
|
||
|
||
1. Creates a new ACT with sub set to Agent B's identifier.
|
||
|
||
2. Sets cap to a subset of A's own authorized capabilities, with
|
||
constraints at least as restrictive as those in A's mandate.
|
||
|
||
3. Sets del.depth to A's own del.depth + 1.
|
||
|
||
4. Sets del.max_depth to no more than the del.max_depth value in A's
|
||
own mandate.
|
||
|
||
5. Adds a chain entry containing A's identifier as delegator, the
|
||
jti of A's own mandate, and a sig value computed as:
|
||
|
||
sig = Sign(A.private_key, SHA-256(canonical_ACT_phase1_bytes))
|
||
|
||
where canonical_ACT_phase1_bytes is the UTF-8 encoded bytes of
|
||
the JWS Compact Serialization of A's Phase 1 ACT.
|
||
|
||
6. Signs the new ACT with A's private key.
|
||
|
||
6.2. Privilege Reduction Requirements
|
||
|
||
When issuing a delegated ACT, the issuing agent MUST reduce
|
||
privileges by one or more of:
|
||
|
||
* Removing capabilities (sub-set of parent capabilities only).
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 25]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
* Adding stricter constraints (lower rate limits, narrower domains,
|
||
shorter time windows, lower data classification ceiling).
|
||
|
||
* Reducing token lifetime (exp closer to iat).
|
||
|
||
* Reducing del.max_depth.
|
||
|
||
The issuing agent MUST NOT grant capabilities not present in its own
|
||
mandate. Capability escalation via delegation is prohibited and MUST
|
||
be detected and rejected by verifiers.
|
||
|
||
For well-known numeric constraints (e.g., max_records,
|
||
max_requests_per_hour), "more restrictive" means a numerically lower
|
||
or equal value. For well-known enumerated constraints (e.g.,
|
||
data_sensitivity), "more restrictive" means a value that is equal or
|
||
higher in the defined ordering ("public" < "internal" <
|
||
"confidential" < "restricted"). For unknown or domain-specific
|
||
constraint keys, verifiers MUST treat the constraint as non-
|
||
comparable and MUST reject the delegation unless the delegated
|
||
constraint value is byte-for-byte identical to the parent constraint
|
||
value.
|
||
|
||
6.3. Delegation Verification
|
||
|
||
A verifier receiving a delegated ACT MUST:
|
||
|
||
1. Verify the ACT's own signature (Section 8.1).
|
||
|
||
2. For each entry in del.chain, in order from index 0 to del.depth -
|
||
1: a. Retrieve the public key for entry.delegator. b. Verify
|
||
that entry.sig is a valid signature over the SHA-256 hash of the
|
||
referenced parent ACT (identified by entry.jti). c. Verify that
|
||
the capabilities in the current ACT are a subset of the
|
||
capabilities in the parent ACT, per the constraint comparison
|
||
rules in Section 6.2.
|
||
|
||
3. Verify that del.depth does not exceed del.max_depth.
|
||
|
||
4. Verify that del.chain length equals del.depth.
|
||
|
||
If any step fails, the ACT MUST be rejected.
|
||
|
||
7. DAG Structure and Causal Ordering
|
||
|
||
ACTs in Phase 2 form a DAG over the pred (predecessor) claim. The
|
||
DAG encodes causal dependencies: a task MAY NOT begin before all its
|
||
parent tasks are completed.
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 26]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
7.1. DAG Validation
|
||
|
||
When processing a Phase 2 ACT, implementations MUST:
|
||
|
||
1. *Uniqueness*: Verify the jti is unique within the workflow (wid)
|
||
or globally if wid is absent.
|
||
|
||
2. *Predecessor Existence*: Verify every jti in pred corresponds to
|
||
a Phase 2 ACT available in the ACT store or audit ledger.
|
||
|
||
3. *Temporal Ordering*: Verify that for each parent: parent.exec_ts
|
||
< child.exec_ts + clock_skew_tolerance (RECOMMENDED tolerance: 30
|
||
seconds). Causal ordering is primarily enforced by DAG
|
||
structure, not timestamps.
|
||
|
||
4. *Acyclicity*: Following parent references MUST NOT lead back to
|
||
the current ACT's jti. Implementations MUST enforce a maximum
|
||
ancestor traversal limit (RECOMMENDED: 10,000 nodes).
|
||
|
||
5. *Capability Consistency*: Verify that exec_act matches one of the
|
||
action values in the cap array from Phase 1.
|
||
|
||
7.2. Root Tasks and Fan-in
|
||
|
||
A root task has pred = []. A workflow MAY have multiple root tasks
|
||
representing parallel branches with no shared predecessor.
|
||
|
||
Fan-in — a task with multiple parents — is expressed naturally:
|
||
|
||
{
|
||
"pred": [
|
||
"550e8400-e29b-41d4-a716-446655440001",
|
||
"550e8400-e29b-41d4-a716-446655440002"
|
||
]
|
||
}
|
||
|
||
This indicates the current task depends on the completion of both
|
||
referenced parent tasks, which MAY have been executed in parallel by
|
||
different agents.
|
||
|
||
7.3. DAG vs Linear Delegation Chains
|
||
|
||
Several concurrent proposals for agent authorization model delegation
|
||
as an ordered, linear chain of tokens or principals. Examples
|
||
include the actchain claim of
|
||
[I-D.oauth-transaction-tokens-for-agents], the Agentic JWT
|
||
construction of [AgenticJWT], the AIP / Interaction-Bound Context
|
||
Token (IBCT) model of [AIP-IBCT], and the delegation record defined
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 27]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
in [I-D.helixar-hdp-agentic-delegation]. In each of these designs,
|
||
the trail from the originator to the final executor is represented as
|
||
an ordered array recording one predecessor per hop.
|
||
|
||
7.3.1. What Linear Chains Express Well
|
||
|
||
Linear chains are a natural fit for simple sequential delegation:
|
||
agent A delegates to agent B, which delegates to agent C. The chain
|
||
records the history of that single hand-off in order, and verifiers
|
||
can walk from the current holder back to the originator without
|
||
branching. For interactive user-to-agent-to-service flows, where
|
||
each step has exactly one predecessor, a linear chain is both
|
||
sufficient and compact.
|
||
|
||
7.3.2. Limitations of Linear Chains
|
||
|
||
Agentic workflows in practice are rarely purely linear. Planner
|
||
agents dispatch parallel sub-tasks; synthesizer agents consume
|
||
results from multiple independent branches; tool calls execute
|
||
concurrently and their outputs are merged. A linear chain cannot
|
||
faithfully represent the following common topologies:
|
||
|
||
* *Fork*: A single task spawns multiple independent sub-tasks. A
|
||
linear chain cannot express that two concurrent sub-executions
|
||
share a common parent authorization but are otherwise independent;
|
||
each sub-task would either omit its siblings or fabricate a false
|
||
ordering between them.
|
||
|
||
* *Join (fan-in)*: A task whose output depends on results from
|
||
several predecessors has no single prior hop. Linear chains
|
||
cannot express multiple-parent relationships without either
|
||
collapsing parallel branches into an arbitrary order or
|
||
duplicating records.
|
||
|
||
* *Diamond dependencies*: A planner dispatches parallel work and
|
||
later synthesizes the results. The synthesis step depends on
|
||
every branch, and all branches depend on the same planner. This
|
||
diamond shape requires a DAG; a linear chain forces the verifier
|
||
to pick one branch and discard the others.
|
||
|
||
* *Cross-chain references*: When two independently authorized chains
|
||
produce outputs that are later combined (e.g., a shared cache
|
||
lookup and a fresh retrieval), linear chains force a single
|
||
history and cannot record that the combined result has two
|
||
distinct provenances.
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 28]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
7.3.3. ACT's DAG Approach
|
||
|
||
As specified in Section 4.3, the pred claim is an array of parent jti
|
||
values rather than a single scalar. This allows an ACT to record:
|
||
|
||
* Zero parents (a root task, pred = []);
|
||
|
||
* Exactly one parent (a linear chain, equivalent to the single-
|
||
predecessor designs referenced above);
|
||
|
||
* Multiple parents (fan-in from parallel branches); and
|
||
|
||
* Any acyclic shape that matches the actual execution structure.
|
||
|
||
The following example illustrates a diamond workflow. A research
|
||
agent (A) dispatches a web-search agent (B) and a code-analysis agent
|
||
(C) in parallel; both complete, and their outputs are combined by a
|
||
writer agent (D):
|
||
|
||
+-----+
|
||
| A | pred = []
|
||
+-----+
|
||
/ \
|
||
v v
|
||
+---+ +---+
|
||
| B | | C | pred = [A.jti]
|
||
+---+ +---+
|
||
\ /
|
||
v v
|
||
+-----+
|
||
| D | pred = [B.jti, C.jti]
|
||
+-----+
|
||
|
||
A linear actchain representation cannot express that D depends on
|
||
both B and C. At best, it can record one of the two parents and lose
|
||
the other, or serialize B and C into a false sequential order.
|
||
|
||
7.3.4. Verifiability Implications
|
||
|
||
With a DAG representation, an auditor holding the set of Phase 2 ACTs
|
||
for a workflow can reconstruct the full execution graph, not just one
|
||
chain per final record. This matters for:
|
||
|
||
* *Debugging*: identifying which branch contributed an erroneous
|
||
input to a downstream synthesis.
|
||
|
||
* *Compliance*: demonstrating that every input to a regulated
|
||
decision was itself authorized, not only the most recent hop.
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 29]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
* *Tamper-evidence*: detecting that a branch has been omitted, since
|
||
the surviving siblings' pred arrays name the missing predecessor
|
||
by jti.
|
||
|
||
7.3.5. Interoperability with Linear-Chain Designs
|
||
|
||
ACT's DAG reduces to a linear chain in the degenerate case where
|
||
every pred array has length zero or one. An implementation that
|
||
requires linear-chain semantics MAY treat such ACTs as equivalent to
|
||
actchain-style records and ignore the fork/join capability. The
|
||
reverse reduction is not available: a linear-chain-only design cannot
|
||
represent ACT DAG topologies without loss of information.
|
||
|
||
ACT therefore takes the linear chain as a strict subset of its model
|
||
rather than as a competing approach. The DAG generalization is
|
||
deliberate and is motivated by the concurrent, branching nature of
|
||
real agentic executions rather than by any deficiency in the linear-
|
||
chain designs for the sequential cases they target.
|
||
|
||
8. Verification Procedure
|
||
|
||
8.1. Authorization Phase Verification
|
||
|
||
A receiving agent MUST verify a Phase 1 ACT as follows:
|
||
|
||
1. Parse JWS Compact Serialization per [RFC7515].
|
||
|
||
2. Verify typ is "act+jwt".
|
||
|
||
3. Verify alg is in the verifier's algorithm allowlist. The
|
||
allowlist MUST NOT include "none" or any symmetric algorithm.
|
||
|
||
4. Retrieve the public key for kid per the applicable trust tier
|
||
(Section 5).
|
||
|
||
5. Verify the JWS signature.
|
||
|
||
6. Verify exp has not passed (with clock skew tolerance:
|
||
RECOMMENDED maximum 5 minutes).
|
||
|
||
7. Verify iat is not unreasonably in the future (RECOMMENDED: no
|
||
more than 30 seconds ahead).
|
||
|
||
8. Verify aud contains the verifier's own identifier.
|
||
|
||
9. Verify iss is a trusted agent identity per local policy.
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 30]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
10. Verify sub matches the verifier's own identifier (the agent is
|
||
the intended recipient of this mandate).
|
||
|
||
11. Verify all required claims are present and well-formed.
|
||
|
||
12. Verify delegation chain (Section 6.3) if del.chain is non-empty.
|
||
|
||
13. Verify capabilities are within policy limits.
|
||
|
||
8.2. Execution Phase Verification
|
||
|
||
In addition to all Phase 1 verification steps, a verifier processing
|
||
a Phase 2 ACT MUST:
|
||
|
||
1. Verify exec_act is present and matches an action in cap.
|
||
|
||
2. Verify pred is present and perform DAG validation (Section 7.1).
|
||
|
||
3. Verify exec_ts is present and is greater than or equal to iat.
|
||
If exec_ts is after exp, implementations SHOULD log a warning but
|
||
MUST NOT reject the record solely on this basis.
|
||
|
||
4. Verify status is present and has a valid value.
|
||
|
||
5. Verify the re-signature was produced by the sub agent (the
|
||
executing agent), not the iss agent (the mandating agent). This
|
||
is verified by checking that the kid in the Phase 2 JOSE header
|
||
corresponds to the sub agent's public key.
|
||
|
||
6. If inp_hash or out_hash are present, verify them against locally
|
||
available input/output data when possible.
|
||
|
||
9. Transport
|
||
|
||
9.1. HTTP Header Transport
|
||
|
||
This specification defines two HTTP [RFC9110] header fields for ACT
|
||
transport:
|
||
|
||
*ACT-Mandate*: Carries a Phase 1 ACT issued by an upstream agent or
|
||
operator. Value is the JWS Compact Serialization of the ACT.
|
||
|
||
GET /api/safety-check HTTP/1.1
|
||
Host: safety-agent.example.com
|
||
ACT-Mandate: eyJhbGci...Phase1ACT...
|
||
|
||
*ACT-Record*: Carries a Phase 2 ACT from a predecessor agent, serving
|
||
as evidence of completed prerequisites.
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 31]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
POST /api/downstream HTTP/1.1
|
||
Host: downstream-agent.example.com
|
||
ACT-Mandate: eyJhbGci...Phase1ACT...
|
||
ACT-Record: eyJhbGci...Phase2ACT...
|
||
|
||
Multiple ACT-Record header lines MAY be included when a task has
|
||
multiple completed predecessors (DAG fan-in). If any single ACT-
|
||
Record fails verification, the receiver MUST reject the entire
|
||
request.
|
||
|
||
9.2. Non-HTTP Transports
|
||
|
||
For non-HTTP transports (MCP stdio, A2A message queues, AMQP, etc.),
|
||
ACTs SHOULD be carried as a dedicated field in the transport's
|
||
metadata envelope. The field name SHOULD be act_mandate for Phase 1
|
||
ACTs and act_record for Phase 2 ACTs. Implementations MUST use the
|
||
JWS Compact Serialization form in all transports.
|
||
|
||
10. Audit Ledger Interface
|
||
|
||
Phase 2 ACTs SHOULD be submitted to an immutable audit ledger. A
|
||
ledger is RECOMMENDED for regulated environments but is not required
|
||
for basic ACT operation. This specification does not mandate a
|
||
specific storage technology.
|
||
|
||
When an audit ledger is deployed, the implementation MUST provide:
|
||
|
||
1. *Append-only semantics*: Once an ACT is recorded, it MUST NOT be
|
||
modified or deleted.
|
||
|
||
2. *Ordering*: A monotonically increasing sequence number per
|
||
recorded ACT.
|
||
|
||
3. *Lookup*: Efficient retrieval by jti value.
|
||
|
||
4. *Integrity*: A cryptographic commitment scheme over recorded ACTs
|
||
(e.g., hash-chaining, Merkle tree anchoring, or SCITT
|
||
registration per [I-D.ietf-scitt-architecture]).
|
||
|
||
11. Security Considerations
|
||
|
||
11.1. Threat Model
|
||
|
||
ACT assumes an adversarial environment where:
|
||
|
||
* Individual agents may be compromised.
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 32]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
* Network paths may be intercepted (mitigated by transport
|
||
security).
|
||
|
||
* Attackers may attempt to replay valid ACTs from prior
|
||
interactions.
|
||
|
||
* Colluding agents may attempt to fabricate execution records.
|
||
|
||
* Agents may attempt privilege escalation via manipulated delegation
|
||
chains.
|
||
|
||
ACT does NOT assume:
|
||
|
||
* A trusted central authority (by design).
|
||
|
||
* Synchronized clocks beyond the stated skew tolerance.
|
||
|
||
* Availability of external network services during verification.
|
||
|
||
11.2. Self-Assertion Limitation
|
||
|
||
Phase 2 ACTs are self-asserted: an executing agent signs its own
|
||
execution record. A compromised agent with an intact private key can
|
||
produce Phase 2 ACTs claiming arbitrary inputs, outputs, and action
|
||
types, as long as the claimed exec_act matches an authorized
|
||
capability.
|
||
|
||
This is a fundamental limitation of self-sovereign attestation. It
|
||
is the same limitation affecting WIMSE ECT [I-D.nennemann-wimse-ect].
|
||
|
||
Mitigations:
|
||
|
||
* *Cross-agent corroboration*: A receiving agent that processes an
|
||
ACT-Record as a prerequisite independently verifies that the
|
||
claimed out_hash matches the data it actually received.
|
||
|
||
* *Ledger sequencing*: An append-only ledger with monotonic sequence
|
||
numbers prevents retroactive insertion of fabricated records.
|
||
|
||
* *SCITT anchoring*: For high-assurance deployments, Phase 2 ACTs
|
||
SHOULD be anchored to a SCITT Transparency Service, providing
|
||
external witness that the record was submitted at a claimed time.
|
||
|
||
11.3. Key Compromise
|
||
|
||
If an agent's private key is compromised, an attacker can issue
|
||
arbitrary Phase 1 mandates (impersonating the agent as an issuer) and
|
||
fabricate Phase 2 records (impersonating the agent as an executor).
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 33]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
Key compromise response:
|
||
|
||
1. The compromised agent's identifier MUST be added to all
|
||
verifiers' deny lists.
|
||
|
||
2. In Tier 2 (PKI) deployments, the certificate MUST be revoked via
|
||
CRL or OCSP.
|
||
|
||
3. In Tier 3 (DID) deployments, the DID Document MUST be updated to
|
||
revoke the compromised key.
|
||
|
||
4. In Tier 1 (pre-shared key) deployments, both parties MUST perform
|
||
an out-of-band key rotation.
|
||
|
||
ACT chains that include records signed by a compromised key MUST be
|
||
treated as potentially tainted from the point of compromise. Audit
|
||
systems MUST flag all ACTs signed after the estimated compromise
|
||
time.
|
||
|
||
11.4. Replay Attack Prevention
|
||
|
||
jti uniqueness within the applicable scope (workflow or global)
|
||
provides replay detection. Verifiers MUST reject ACTs whose jti has
|
||
already been seen and processed.
|
||
|
||
exp provides a time-bounded replay window. Verifiers MUST reject
|
||
expired ACTs. The combination of jti and exp means that replay
|
||
detection state only needs to be maintained for the duration of token
|
||
lifetimes.
|
||
|
||
11.5. Equivocation
|
||
|
||
In standalone deployment (no audit ledger, no SCITT anchoring), ACT
|
||
does NOT provide non-equivocation guarantees. A compromised agent
|
||
can maintain two valid ACT chains — presenting Phase 2 records with
|
||
different out_hash values to different verifiers — and both will pass
|
||
independent verification.
|
||
|
||
*Deployments claiming DORA [DORA] Article 10/11 compliance or EU AI
|
||
Act [EUAIA] Article 12 compliance MUST use one of:*
|
||
|
||
(a) A shared append-only audit ledger visible to all relevant
|
||
parties, with cryptographic integrity (hash chaining or Merkle
|
||
trees).
|
||
|
||
(b) SCITT anchoring [I-D.ietf-scitt-architecture] providing external
|
||
Transparency Service receipts.
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 34]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
Standalone ACT provides tamper detection (a verifier can detect
|
||
modification of a record it has seen) but not split-view prevention
|
||
(a verifier cannot detect a different record shown to another
|
||
verifier).
|
||
|
||
11.6. Privilege Escalation
|
||
|
||
Verifiers MUST check that each step in del.chain reduces or maintains
|
||
(never increases) the capabilities relative to the preceding step.
|
||
Implementations MUST reject ACTs where:
|
||
|
||
* del.depth exceeds del.max_depth.
|
||
|
||
* cap contains actions not present in any referenced parent ACT.
|
||
|
||
* Constraints in cap are less restrictive than those in the parent.
|
||
|
||
11.7. Denial of Service
|
||
|
||
ACT verification is more computationally expensive than standard JWT
|
||
validation due to delegation chain verification and DAG traversal.
|
||
|
||
Mitigations:
|
||
|
||
* Reject ACTs larger than 64KB before parsing.
|
||
|
||
* Enforce maximum del.chain length (RECOMMENDED: 10 entries).
|
||
|
||
* Enforce maximum DAG ancestor traversal depth (RECOMMENDED: 10,000
|
||
nodes, Section 7.1).
|
||
|
||
* Cache verification results for recently seen jti values within the
|
||
token lifetime window.
|
||
|
||
12. Privacy Considerations
|
||
|
||
ACT tokens and audit ledger records may contain information that
|
||
identifies agents, organizations, or individuals. Implementations
|
||
SHOULD apply data minimization principles:
|
||
|
||
* task.created_by SHOULD use a pseudonymous identifier rather than a
|
||
personal email address or real name.
|
||
|
||
* task.purpose SHOULD use a controlled vocabulary code rather than
|
||
free-text descriptions that may contain personal data.
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 35]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
* del.chain entries reveal organizational structure. Cross-
|
||
organizational delegation chains SHOULD use Tier 3 (DID)
|
||
identifiers that do not reveal organizational affiliation.
|
||
|
||
* inp_hash and out_hash are hashes of data, not the data itself, and
|
||
do not constitute personal data under GDPR Article 4(1) provided
|
||
the underlying data is not trivially reversible (e.g., hashes of
|
||
very short strings).
|
||
|
||
For GDPR Article 17 (right to erasure) compliance, audit ledgers
|
||
SHOULD store only ACT tokens (which contain hashes, not raw data) and
|
||
SHOULD implement crypto-shredding for any associated encrypted
|
||
payloads.
|
||
|
||
13. IANA Considerations
|
||
|
||
13.1. Media Type Registration
|
||
|
||
This document requests registration of the following media type:
|
||
|
||
* Type name: application
|
||
|
||
* Subtype name: act+jwt
|
||
|
||
* Required parameters: none
|
||
|
||
* Encoding considerations: binary (base64url-encoded JWT)
|
||
|
||
* Security considerations: See Section 11.
|
||
|
||
* Interoperability considerations: See Section 8.1.
|
||
|
||
* Specification: This document.
|
||
|
||
13.2. HTTP Header Field Registration
|
||
|
||
This document requests registration of the following HTTP header
|
||
fields in the "Hypertext Transfer Protocol (HTTP) Field Name
|
||
Registry":
|
||
|
||
* Header field name: ACT-Mandate
|
||
|
||
* Applicable protocol: HTTP
|
||
|
||
* Status: permanent
|
||
|
||
* Specification: This document, Section 9.1.
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 36]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
* Header field name: ACT-Record
|
||
|
||
* Applicable protocol: HTTP
|
||
|
||
* Status: permanent
|
||
|
||
* Specification: This document, Section 9.1.
|
||
|
||
13.3. JWT Claims Registration
|
||
|
||
This document requests registration of the following claims in the
|
||
IANA "JSON Web Token Claims" registry:
|
||
|
||
+============+====================================+===============+
|
||
| Claim Name | Description | Reference |
|
||
+============+====================================+===============+
|
||
| wid | Workflow identifier | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| task | Task authorization context | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| cap | Capabilities with constraints | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| oversight | Human oversight requirements | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| del | Delegation provenance chain | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| exec_act | Executed action identifier | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| pred | Predecessor task identifiers (DAG) | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| inp_hash | SHA-256 hash of task input | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| out_hash | SHA-256 hash of task output | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| exec_ts | Actual execution timestamp | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| status | Execution status | This document |
|
||
+------------+------------------------------------+---------------+
|
||
| err | Execution error context | This document |
|
||
+------------+------------------------------------+---------------+
|
||
|
||
Table 1
|
||
|
||
14. References
|
||
|
||
14.1. Normative References
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 37]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
|
||
Requirement Levels", BCP 14, RFC 2119,
|
||
DOI 10.17487/RFC2119, March 1997,
|
||
<https://www.rfc-editor.org/rfc/rfc2119>.
|
||
|
||
[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
|
||
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
|
||
2015, <https://www.rfc-editor.org/rfc/rfc7515>.
|
||
|
||
[RFC7517] Jones, M., "JSON Web Key (JWK)", RFC 7517,
|
||
DOI 10.17487/RFC7517, May 2015,
|
||
<https://www.rfc-editor.org/rfc/rfc7517>.
|
||
|
||
[RFC7518] Jones, M., "JSON Web Algorithms (JWA)", RFC 7518,
|
||
DOI 10.17487/RFC7518, May 2015,
|
||
<https://www.rfc-editor.org/rfc/rfc7518>.
|
||
|
||
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
|
||
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
|
||
<https://www.rfc-editor.org/rfc/rfc7519>.
|
||
|
||
[RFC8037] Liusvaara, I., "CFRG Elliptic Curve Diffie-Hellman (ECDH)
|
||
and Signatures in JSON Object Signing and Encryption
|
||
(JOSE)", RFC 8037, DOI 10.17487/RFC8037, January 2017,
|
||
<https://www.rfc-editor.org/rfc/rfc8037>.
|
||
|
||
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
|
||
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
|
||
May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.
|
||
|
||
[RFC9110] Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke,
|
||
Ed., "HTTP Semantics", STD 97, RFC 9110,
|
||
DOI 10.17487/RFC9110, June 2022,
|
||
<https://www.rfc-editor.org/rfc/rfc9110>.
|
||
|
||
[RFC9562] Davis, K., Peabody, B., and P. Leach, "Universally Unique
|
||
IDentifiers (UUIDs)", RFC 9562, DOI 10.17487/RFC9562, May
|
||
2024, <https://www.rfc-editor.org/rfc/rfc9562>.
|
||
|
||
14.2. Informative References
|
||
|
||
[A2A-SPEC] Google, "Agent2Agent (A2A) Protocol",
|
||
<https://github.com/a2aproject/A2A>.
|
||
|
||
[AgenticJWT]
|
||
"Agentic JWT: A JSON Web Token Profile for Delegated Agent
|
||
Authorization", 2025, <https://arxiv.org/abs/2509.13597>.
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 38]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
[AIP-IBCT] S., P., "AIP: Agent Interaction Protocol with Interaction-
|
||
Bound Context Tokens", March 2026,
|
||
<https://arxiv.org/abs/2603.24775>.
|
||
|
||
[AUTOGEN] Microsoft, "AutoGen Documentation",
|
||
<https://microsoft.github.io/autogen/>.
|
||
|
||
[CREWAI] CrewAI, "CrewAI Documentation",
|
||
<https://docs.crewai.com/>.
|
||
|
||
[DID-KEY] D., L., "The did:key Method v0.7", 2021,
|
||
<https://w3c-ccg.github.io/did-method-key/>.
|
||
|
||
[DID-WEB] O., S., "did:web Method Specification", 2022,
|
||
<https://w3c-ccg.github.io/did-method-web/>.
|
||
|
||
[DORA] European Parliament, "Digital Operational Resilience Act
|
||
(DORA), Regulation (EU) 2022/2554", 2022,
|
||
<https://eur-lex.europa.eu/eli/reg/2022/2554/oj>.
|
||
|
||
[EUAIA] European Parliament, "EU Artificial Intelligence Act,
|
||
Regulation (EU) 2024/1689", 2024,
|
||
<https://eur-lex.europa.eu/eli/reg/2024/1689/oj>.
|
||
|
||
[I-D.aap-oauth-profile]
|
||
A., C., "Agent Authorization Profile (AAP) for OAuth 2.0",
|
||
Work in Progress, Internet-Draft, draft-aap-oauth-profile-
|
||
01, February 2026, <https://datatracker.ietf.org/doc/
|
||
draft-aap-oauth-profile/>.
|
||
|
||
[I-D.emirdag-scitt-ai-agent-execution]
|
||
Emirdag, "A SCITT Profile for AI Agent Execution Records",
|
||
Work in Progress, Internet-Draft, draft-emirdag-scitt-ai-
|
||
agent-execution-00, April 2026,
|
||
<https://datatracker.ietf.org/doc/draft-emirdag-scitt-ai-
|
||
agent-execution/>.
|
||
|
||
[I-D.helixar-hdp-agentic-delegation]
|
||
Helixar, "Helixar Delegation Protocol (HDP) for Agentic
|
||
Delegation", Work in Progress, Internet-Draft, draft-
|
||
helixar-hdp-agentic-delegation-00, 2026,
|
||
<https://datatracker.ietf.org/doc/draft-helixar-hdp-
|
||
agentic-delegation/>.
|
||
|
||
[I-D.ietf-scitt-architecture]
|
||
Birkholz, H., Delignat-Lavaud, A., Fournet, C., Deshpande,
|
||
Y., and S. Lasker, "An Architecture for Trustworthy and
|
||
Transparent Digital Supply Chains", Work in Progress,
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 39]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
Internet-Draft, draft-ietf-scitt-architecture-22, 10
|
||
October 2025, <https://datatracker.ietf.org/doc/html/
|
||
draft-ietf-scitt-architecture-22>.
|
||
|
||
[I-D.nennemann-wimse-ect]
|
||
Nennemann, C., "Execution Context Tokens for Distributed
|
||
Agentic Workflows", Work in Progress, Internet-Draft,
|
||
draft-nennemann-wimse-ect-02, 2026,
|
||
<https://datatracker.ietf.org/doc/draft-nennemann-wimse-
|
||
ect/>.
|
||
|
||
[I-D.oauth-transaction-tokens-for-agents]
|
||
G., F., "Transaction Tokens for Agentic AI Systems", Work
|
||
in Progress, Internet-Draft, draft-oauth-transaction-
|
||
tokens-for-agents-06, 2026,
|
||
<https://datatracker.ietf.org/doc/draft-oauth-transaction-
|
||
tokens-for-agents/>.
|
||
|
||
[IEC62304] IEC, "Medical device software — Software life cycle
|
||
processes, IEC 62304:2006+AMD1:2015", 2015,
|
||
<https://www.iec.ch/>.
|
||
|
||
[LANGGRAPH]
|
||
LangChain, "LangGraph Documentation",
|
||
<https://langchain-ai.github.io/langgraph/>.
|
||
|
||
[MCP-SPEC] "Model Context Protocol Specification", 25 November 2025,
|
||
<https://modelcontextprotocol.io/
|
||
specification/2025-11-25>.
|
||
|
||
[OPENAI-AGENTS-SDK]
|
||
OpenAI, "OpenAI Agents SDK",
|
||
<https://openai.github.io/openai-agents-python/>.
|
||
|
||
[RFC7009] Lodderstedt, T., Ed., Dronia, S., and M. Scurtescu, "OAuth
|
||
2.0 Token Revocation", RFC 7009, DOI 10.17487/RFC7009,
|
||
August 2013, <https://www.rfc-editor.org/rfc/rfc7009>.
|
||
|
||
[RFC8693] Jones, M., Nadalin, A., Campbell, B., Ed., Bradley, J.,
|
||
and C. Mortimore, "OAuth 2.0 Token Exchange", RFC 8693,
|
||
DOI 10.17487/RFC8693, January 2020,
|
||
<https://www.rfc-editor.org/rfc/rfc8693>.
|
||
|
||
[SentinelAgent]
|
||
Patil, "SentinelAgent: A Formal Delegation Chain Calculus
|
||
for Verifiable Agent Authorization", April 2026,
|
||
<https://arxiv.org/abs/2604.02767>.
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 40]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
[W3C-DID] M., S., "Decentralized Identifiers (DIDs) v1.0", July
|
||
2022, <https://www.w3.org/TR/did-core/>.
|
||
|
||
Appendix A: Complete JSON Schema
|
||
|
||
The following JSON Schema (2020-12) describes the claim set of ACT
|
||
Phase 1 (Authorization Mandate) and Phase 2 (Execution Record)
|
||
tokens. A token is a Phase 2 record if and only if it contains the
|
||
exec_act, exec_ts, pred, and status claims; otherwise it is a Phase 1
|
||
mandate. The schema validates structure only; semantic rules
|
||
(capability subset on delegation, exec_act membership in cap, DAG
|
||
acyclicity, depth bounds) are specified normatively in the body of
|
||
this document and cannot be expressed in JSON Schema.
|
||
|
||
{
|
||
"$schema": "https://json-schema.org/draft/2020-12/schema",
|
||
"$id": "urn:ietf:params:act:schema:token",
|
||
"title": "Agent Context Token (ACT)",
|
||
"type": "object",
|
||
"oneOf": [
|
||
{ "$ref": "#/$defs/phase1" },
|
||
{ "$ref": "#/$defs/phase2" }
|
||
],
|
||
"$defs": {
|
||
"actionName": {
|
||
"type": "string",
|
||
"pattern": "^[A-Za-z][A-Za-z0-9_-]*(\\.[A-Za-z][A-Za-z0-9_-]*)*$"
|
||
},
|
||
"numericDate": { "type": "integer", "minimum": 0 },
|
||
"uuid": {
|
||
"type": "string",
|
||
"format": "uuid"
|
||
},
|
||
"audience": {
|
||
"oneOf": [
|
||
{ "type": "string" },
|
||
{
|
||
"type": "array",
|
||
"items": { "type": "string" },
|
||
"minItems": 1
|
||
}
|
||
]
|
||
},
|
||
"task": {
|
||
"type": "object",
|
||
"required": ["purpose"],
|
||
"properties": {
|
||
"purpose": { "type": "string", "minLength": 1 },
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 41]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
"data_sensitivity": {
|
||
"type": "string",
|
||
"enum": [
|
||
"public", "internal", "confidential", "restricted"
|
||
]
|
||
},
|
||
"created_by": { "type": "string" },
|
||
"expires_at": { "$ref": "#/$defs/numericDate" }
|
||
},
|
||
"additionalProperties": true
|
||
},
|
||
"capability": {
|
||
"type": "object",
|
||
"required": ["action"],
|
||
"properties": {
|
||
"action": { "$ref": "#/$defs/actionName" },
|
||
"constraints": { "type": "object" }
|
||
},
|
||
"additionalProperties": false
|
||
},
|
||
"oversight": {
|
||
"type": "object",
|
||
"properties": {
|
||
"requires_approval_for": {
|
||
"type": "array",
|
||
"items": { "$ref": "#/$defs/actionName" }
|
||
},
|
||
"approval_ref": { "type": "string" }
|
||
},
|
||
"additionalProperties": false
|
||
},
|
||
"delegationEntry": {
|
||
"type": "object",
|
||
"required": ["delegator", "jti", "sig"],
|
||
"properties": {
|
||
"delegator": { "type": "string" },
|
||
"jti": { "$ref": "#/$defs/uuid" },
|
||
"sig": { "type": "string" }
|
||
},
|
||
"additionalProperties": false
|
||
},
|
||
"delegation": {
|
||
"type": "object",
|
||
"required": ["depth", "max_depth", "chain"],
|
||
"properties": {
|
||
"depth": { "type": "integer", "minimum": 0 },
|
||
"max_depth": { "type": "integer", "minimum": 0 },
|
||
"chain": {
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 42]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
"type": "array",
|
||
"items": { "$ref": "#/$defs/delegationEntry" }
|
||
}
|
||
},
|
||
"additionalProperties": false
|
||
},
|
||
"error": {
|
||
"type": "object",
|
||
"required": ["code"],
|
||
"properties": {
|
||
"code": { "type": "string" },
|
||
"detail": { "type": "string" }
|
||
},
|
||
"additionalProperties": false
|
||
},
|
||
"commonClaims": {
|
||
"type": "object",
|
||
"required": [
|
||
"iss", "sub", "aud", "iat", "exp", "jti", "task", "cap"
|
||
],
|
||
"properties": {
|
||
"iss": { "type": "string" },
|
||
"sub": { "type": "string" },
|
||
"aud": { "$ref": "#/$defs/audience" },
|
||
"iat": { "$ref": "#/$defs/numericDate" },
|
||
"exp": { "$ref": "#/$defs/numericDate" },
|
||
"jti": { "$ref": "#/$defs/uuid" },
|
||
"wid": { "$ref": "#/$defs/uuid" },
|
||
"task": { "$ref": "#/$defs/task" },
|
||
"cap": {
|
||
"type": "array",
|
||
"minItems": 1,
|
||
"items": { "$ref": "#/$defs/capability" }
|
||
},
|
||
"oversight": { "$ref": "#/$defs/oversight" },
|
||
"del": { "$ref": "#/$defs/delegation" }
|
||
}
|
||
},
|
||
"phase1": {
|
||
"allOf": [{ "$ref": "#/$defs/commonClaims" }],
|
||
"not": {
|
||
"anyOf": [
|
||
{ "required": ["exec_act"] },
|
||
{ "required": ["exec_ts"] },
|
||
{ "required": ["status"] }
|
||
]
|
||
}
|
||
},
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 43]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
"phase2": {
|
||
"allOf": [{ "$ref": "#/$defs/commonClaims" }],
|
||
"required": ["exec_act", "pred", "exec_ts", "status"],
|
||
"properties": {
|
||
"exec_act": { "$ref": "#/$defs/actionName" },
|
||
"pred": {
|
||
"type": "array",
|
||
"items": { "$ref": "#/$defs/uuid" }
|
||
},
|
||
"inp_hash": { "type": "string" },
|
||
"out_hash": { "type": "string" },
|
||
"exec_ts": { "$ref": "#/$defs/numericDate" },
|
||
"status": {
|
||
"type": "string",
|
||
"enum": ["completed", "failed", "partial"]
|
||
},
|
||
"err": { "$ref": "#/$defs/error" }
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
Appendix B: Test Vectors
|
||
|
||
All vectors in this appendix are produced by the reference
|
||
implementation using fixed Ed25519 seeds and fixed identifiers, and
|
||
are therefore reproducible. The base timestamp (iat) is 1772064000
|
||
(2026-02-26T00:00:00Z). Long Base64url values are wrapped for
|
||
display only; line breaks are not part of the value.
|
||
|
||
B.0. Key Material
|
||
|
||
Three Ed25519 key pairs are used, identified by kid. Keys are given
|
||
in JWK [RFC7517] form using the Ed25519 OKP encoding [RFC8037]; "d"
|
||
is the private seed and "x" is the public key, both Base64url-
|
||
encoded. These seeds are recognizable test patterns and MUST NOT be
|
||
used in production.
|
||
|
||
{
|
||
"kty": "OKP",
|
||
"crv": "Ed25519",
|
||
"kid": "iss-key",
|
||
"d": "AAECAwQFBgcICQoLDA0ODxAREhMUFRYXGBkaGxwdHh8",
|
||
"x": "A6EHv_POEL4dcN0Y50vAmWfk1jCbpQ1fHdyGZBJVMbg"
|
||
}
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 44]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"kty": "OKP",
|
||
"crv": "Ed25519",
|
||
"kid": "sub-key",
|
||
"d": "ICEiIyQlJicoKSorLC0uLzAxMjM0NTY3ODk6Ozw9Pj8",
|
||
"x": "Kay64UG8yvCyLhqU000LxzYeUm0L_hLIl5S8kyKWbdc"
|
||
}
|
||
|
||
{
|
||
"kty": "OKP",
|
||
"crv": "Ed25519",
|
||
"kid": "agent-c-key",
|
||
"d": "QEFCQ0RFRkdISUpLTE1OT1BRUlNUVVZXWFlaW1xdXl8",
|
||
"x": "JUO5L_EJVRFHatyDadtt3JM2ZaEZeN2hQE7hBmypVZ0"
|
||
}
|
||
|
||
B.1. Valid Phase 1 ACT: root mandate, Tier 1 (Ed25519), no delegation
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "iss-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 45]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": [
|
||
"agent-subject",
|
||
"https://ledger.example.com"
|
||
],
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440001",
|
||
"task": {
|
||
"purpose": "validate_data",
|
||
"data_sensitivity": "restricted"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data",
|
||
"constraints": {
|
||
"max_records": 10
|
||
}
|
||
},
|
||
{
|
||
"action": "write.result"
|
||
}
|
||
],
|
||
"wid": "a0b1c2d3-e4f5-6789-abcd-ef0123456789",
|
||
"del": {
|
||
"depth": 0,
|
||
"max_depth": 2,
|
||
"chain": []
|
||
}
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJpc3Mta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjpbImFnZW50LXN1YmplY3QiLCJodHRwczovL2xlZGdlci5leGFtcGxlLmNvbSJd
|
||
LCJpYXQiOjE3NzIwNjQwMDAsImV4cCI6MTc3MjA2NDkwMCwianRpIjoiNTUwZTg0
|
||
MDAtZTI5Yi00MWQ0LWE3MTYtNDQ2NjU1NDQwMDAxIiwidGFzayI6eyJwdXJwb3Nl
|
||
IjoidmFsaWRhdGVfZGF0YSIsImRhdGFfc2Vuc2l0aXZpdHkiOiJyZXN0cmljdGVk
|
||
In0sImNhcCI6W3siYWN0aW9uIjoicmVhZC5kYXRhIiwiY29uc3RyYWludHMiOnsi
|
||
bWF4X3JlY29yZHMiOjEwfX0seyJhY3Rpb24iOiJ3cml0ZS5yZXN1bHQifV0sIndp
|
||
ZCI6ImEwYjFjMmQzLWU0ZjUtNjc4OS1hYmNkLWVmMDEyMzQ1Njc4OSIsImRlbCI6
|
||
eyJkZXB0aCI6MCwibWF4X2RlcHRoIjoyLCJjaGFpbiI6W119fQ._nVgyp4X0zYvy
|
||
ylbyBgE_CWKAVdEMFgHjHIUkhxEsr83PQw_rzxNryDd179_KdkCo_kxWDbfmEQV-
|
||
JA1-pknBA
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 46]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
Expected result: Accept. The signature verifies under kid "iss-key"
|
||
and all required Phase 1 claims are present.
|
||
|
||
B.2. Valid Phase 2 ACT: completed execution (transition from B.1)
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "sub-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 47]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": [
|
||
"agent-subject",
|
||
"https://ledger.example.com"
|
||
],
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440001",
|
||
"task": {
|
||
"purpose": "validate_data",
|
||
"data_sensitivity": "restricted"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data",
|
||
"constraints": {
|
||
"max_records": 10
|
||
}
|
||
},
|
||
{
|
||
"action": "write.result"
|
||
}
|
||
],
|
||
"exec_act": "read.data",
|
||
"pred": [],
|
||
"exec_ts": 1772064300,
|
||
"status": "completed",
|
||
"wid": "a0b1c2d3-e4f5-6789-abcd-ef0123456789",
|
||
"del": {
|
||
"depth": 0,
|
||
"max_depth": 2,
|
||
"chain": []
|
||
},
|
||
"inp_hash": "DHooOQxm8XoCuW4a2BOMC2ZP8VyzFYj1gRvKzRdfX_g",
|
||
"out_hash": "n24FIk7teYuF6yXfVBqJ9THKIWuU9C0M5qlGlhLtx2U"
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 48]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJzdWIta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjpbImFnZW50LXN1YmplY3QiLCJodHRwczovL2xlZGdlci5leGFtcGxlLmNvbSJd
|
||
LCJpYXQiOjE3NzIwNjQwMDAsImV4cCI6MTc3MjA2NDkwMCwianRpIjoiNTUwZTg0
|
||
MDAtZTI5Yi00MWQ0LWE3MTYtNDQ2NjU1NDQwMDAxIiwidGFzayI6eyJwdXJwb3Nl
|
||
IjoidmFsaWRhdGVfZGF0YSIsImRhdGFfc2Vuc2l0aXZpdHkiOiJyZXN0cmljdGVk
|
||
In0sImNhcCI6W3siYWN0aW9uIjoicmVhZC5kYXRhIiwiY29uc3RyYWludHMiOnsi
|
||
bWF4X3JlY29yZHMiOjEwfX0seyJhY3Rpb24iOiJ3cml0ZS5yZXN1bHQifV0sImV4
|
||
ZWNfYWN0IjoicmVhZC5kYXRhIiwicHJlZCI6W10sImV4ZWNfdHMiOjE3NzIwNjQz
|
||
MDAsInN0YXR1cyI6ImNvbXBsZXRlZCIsIndpZCI6ImEwYjFjMmQzLWU0ZjUtNjc4
|
||
OS1hYmNkLWVmMDEyMzQ1Njc4OSIsImRlbCI6eyJkZXB0aCI6MCwibWF4X2RlcHRo
|
||
IjoyLCJjaGFpbiI6W119LCJpbnBfaGFzaCI6IkRIb29PUXhtOFhvQ3VXNGEyQk9N
|
||
QzJaUDhWeXpGWWoxZ1J2S3pSZGZYX2ciLCJvdXRfaGFzaCI6Im4yNEZJazd0ZVl1
|
||
RjZ5WGZWQnFKOVRIS0lXdVU5QzBNNXFsR2xoTHR4MlUifQ.ByEeEiMp2MwLHEeiF
|
||
iaV-fRjJw37VdIWahoaGdtR3EnlRMxI01jN9-TuPnUSDqIAf8yfzbri3FTjb02zX
|
||
h0LBA
|
||
|
||
Expected result: Accept. Phase 2 record; the signature verifies
|
||
under kid "sub-key" and exec_act "read.data" is present in cap.
|
||
|
||
B.3. Valid Phase 2 ACT: fan-in with two predecessor tasks
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "sub-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 49]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": "agent-subject",
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440005",
|
||
"task": {
|
||
"purpose": "merge_results"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "compute.result"
|
||
}
|
||
],
|
||
"exec_act": "compute.result",
|
||
"pred": [
|
||
"550e8400-e29b-41d4-a716-446655440003",
|
||
"550e8400-e29b-41d4-a716-446655440004"
|
||
],
|
||
"exec_ts": 1772064200,
|
||
"status": "completed",
|
||
"wid": "a0b1c2d3-e4f5-6789-abcd-ef0123456789",
|
||
"del": {
|
||
"depth": 0,
|
||
"max_depth": 1,
|
||
"chain": []
|
||
}
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJzdWIta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjoiYWdlbnQtc3ViamVjdCIsImlhdCI6MTc3MjA2NDAwMCwiZXhwIjoxNzcyMDY0
|
||
OTAwLCJqdGkiOiI1NTBlODQwMC1lMjliLTQxZDQtYTcxNi00NDY2NTU0NDAwMDUi
|
||
LCJ0YXNrIjp7InB1cnBvc2UiOiJtZXJnZV9yZXN1bHRzIn0sImNhcCI6W3siYWN0
|
||
aW9uIjoiY29tcHV0ZS5yZXN1bHQifV0sImV4ZWNfYWN0IjoiY29tcHV0ZS5yZXN1
|
||
bHQiLCJwcmVkIjpbIjU1MGU4NDAwLWUyOWItNDFkNC1hNzE2LTQ0NjY1NTQ0MDAw
|
||
MyIsIjU1MGU4NDAwLWUyOWItNDFkNC1hNzE2LTQ0NjY1NTQ0MDAwNCJdLCJleGVj
|
||
X3RzIjoxNzcyMDY0MjAwLCJzdGF0dXMiOiJjb21wbGV0ZWQiLCJ3aWQiOiJhMGIx
|
||
YzJkMy1lNGY1LTY3ODktYWJjZC1lZjAxMjM0NTY3ODkiLCJkZWwiOnsiZGVwdGgi
|
||
OjAsIm1heF9kZXB0aCI6MSwiY2hhaW4iOltdfX0.Koikd5apdJ1LLfdl0n0-arQ4
|
||
nDWbrygFImdE8QMKtWFwE35bIjIlr8ILXcr-0jDOBt0IJa8b_0yZROkUPlEgCA
|
||
|
||
Expected result: Accept. Phase 2 fan-in; pred lists the two
|
||
predecessor jti values from the parallel branches.
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 50]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
B.4. Valid Phase 1 ACT: delegated mandate (depth 1)
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "iss-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-c",
|
||
"aud": "agent-c",
|
||
"iat": 1772064010,
|
||
"exp": 1772064600,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440006",
|
||
"task": {
|
||
"purpose": "delegated_read"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data",
|
||
"constraints": {
|
||
"max_records": 5
|
||
}
|
||
}
|
||
],
|
||
"wid": "a0b1c2d3-e4f5-6789-abcd-ef0123456789",
|
||
"del": {
|
||
"depth": 1,
|
||
"max_depth": 2,
|
||
"chain": [
|
||
{
|
||
"delegator": "agent-issuer",
|
||
"jti": "550e8400-e29b-41d4-a716-446655440001",
|
||
"sig": "cYYbPuSiYxFV1D45qBKkzUo2GZMjkVkN4IEnJt4433CN8MJ6sAEVy4Huqr4ebuF7fCKpvGijOidrOkfY-BJFCQ"
|
||
}
|
||
]
|
||
}
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 51]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJpc3Mta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1jIiwiYXVkIjoiYWdl
|
||
bnQtYyIsImlhdCI6MTc3MjA2NDAxMCwiZXhwIjoxNzcyMDY0NjAwLCJqdGkiOiI1
|
||
NTBlODQwMC1lMjliLTQxZDQtYTcxNi00NDY2NTU0NDAwMDYiLCJ0YXNrIjp7InB1
|
||
cnBvc2UiOiJkZWxlZ2F0ZWRfcmVhZCJ9LCJjYXAiOlt7ImFjdGlvbiI6InJlYWQu
|
||
ZGF0YSIsImNvbnN0cmFpbnRzIjp7Im1heF9yZWNvcmRzIjo1fX1dLCJ3aWQiOiJh
|
||
MGIxYzJkMy1lNGY1LTY3ODktYWJjZC1lZjAxMjM0NTY3ODkiLCJkZWwiOnsiZGVw
|
||
dGgiOjEsIm1heF9kZXB0aCI6MiwiY2hhaW4iOlt7ImRlbGVnYXRvciI6ImFnZW50
|
||
LWlzc3VlciIsImp0aSI6IjU1MGU4NDAwLWUyOWItNDFkNC1hNzE2LTQ0NjY1NTQ0
|
||
MDAwMSIsInNpZyI6ImNZWWJQdVNpWXhGVjFENDVxQktrelVvMkdaTWprVmtONElF
|
||
bkp0NDQzM0NOOE1KNnNBRVZ5NEh1cXI0ZWJ1RjdmQ0twdkdpak9pZHJPa2ZZLUJK
|
||
RkNRIn1dfX0.k4SGmgQrAdUN_f-LsJVAL5A3Q-2NHllGaSx1WOmdbcRzvW2uOfct
|
||
1K0e_zxnd_7UHvLClTE01kKiQ3zU1imtCQ
|
||
|
||
Expected result: Accept. Delegated mandate at depth 1; the delegated
|
||
cap (max_records=5) is a subset of the parent cap (max_records=10).
|
||
|
||
B.5. Valid Phase 2 ACT: delegated execution record
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "agent-c-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 52]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-c",
|
||
"aud": "agent-c",
|
||
"iat": 1772064010,
|
||
"exp": 1772064600,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440006",
|
||
"task": {
|
||
"purpose": "delegated_read"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data",
|
||
"constraints": {
|
||
"max_records": 5
|
||
}
|
||
}
|
||
],
|
||
"exec_act": "read.data",
|
||
"pred": [],
|
||
"exec_ts": 1772064350,
|
||
"status": "completed",
|
||
"wid": "a0b1c2d3-e4f5-6789-abcd-ef0123456789",
|
||
"del": {
|
||
"depth": 1,
|
||
"max_depth": 2,
|
||
"chain": [
|
||
{
|
||
"delegator": "agent-issuer",
|
||
"jti": "550e8400-e29b-41d4-a716-446655440001",
|
||
"sig": "cYYbPuSiYxFV1D45qBKkzUo2GZMjkVkN4IEnJt4433CN8MJ6sAEVy4Huqr4ebuF7fCKpvGijOidrOkfY-BJFCQ"
|
||
}
|
||
]
|
||
}
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 53]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJhZ2VudC1jLWtl
|
||
eSJ9.eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1jIiwiYXVkIjo
|
||
iYWdlbnQtYyIsImlhdCI6MTc3MjA2NDAxMCwiZXhwIjoxNzcyMDY0NjAwLCJqdGk
|
||
iOiI1NTBlODQwMC1lMjliLTQxZDQtYTcxNi00NDY2NTU0NDAwMDYiLCJ0YXNrIjp
|
||
7InB1cnBvc2UiOiJkZWxlZ2F0ZWRfcmVhZCJ9LCJjYXAiOlt7ImFjdGlvbiI6InJ
|
||
lYWQuZGF0YSIsImNvbnN0cmFpbnRzIjp7Im1heF9yZWNvcmRzIjo1fX1dLCJleGV
|
||
jX2FjdCI6InJlYWQuZGF0YSIsInByZWQiOltdLCJleGVjX3RzIjoxNzcyMDY0MzU
|
||
wLCJzdGF0dXMiOiJjb21wbGV0ZWQiLCJ3aWQiOiJhMGIxYzJkMy1lNGY1LTY3ODk
|
||
tYWJjZC1lZjAxMjM0NTY3ODkiLCJkZWwiOnsiZGVwdGgiOjEsIm1heF9kZXB0aCI
|
||
6MiwiY2hhaW4iOlt7ImRlbGVnYXRvciI6ImFnZW50LWlzc3VlciIsImp0aSI6IjU
|
||
1MGU4NDAwLWUyOWItNDFkNC1hNzE2LTQ0NjY1NTQ0MDAwMSIsInNpZyI6ImNZWWJ
|
||
QdVNpWXhGVjFENDVxQktrelVvMkdaTWprVmtONElFbkp0NDQzM0NOOE1KNnNBRVZ
|
||
5NEh1cXI0ZWJ1RjdmQ0twdkdpak9pZHJPa2ZZLUJKRkNRIn1dfX0.dCUyOsyvrRA
|
||
vM7m0WO6LBnIhijckknlbX3kVGxmkKlzekQmKTAJQbM5H2WbACOh3LpB9LW3hgCE
|
||
luEjhd4laAw
|
||
|
||
Expected result: Accept. Phase 2 record for the delegated mandate;
|
||
the signature verifies under kid "agent-c-key".
|
||
|
||
B.6. Invalid: delegation depth exceeds maximum
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "iss-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 54]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": "agent-subject",
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440008",
|
||
"task": {
|
||
"purpose": "bad_depth"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data"
|
||
}
|
||
],
|
||
"del": {
|
||
"depth": 3,
|
||
"max_depth": 2,
|
||
"chain": [
|
||
{
|
||
"delegator": "a",
|
||
"jti": "j1",
|
||
"sig": "sig1"
|
||
},
|
||
{
|
||
"delegator": "b",
|
||
"jti": "j2",
|
||
"sig": "sig2"
|
||
},
|
||
{
|
||
"delegator": "c",
|
||
"jti": "j3",
|
||
"sig": "sig3"
|
||
}
|
||
]
|
||
}
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 55]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJpc3Mta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjoiYWdlbnQtc3ViamVjdCIsImlhdCI6MTc3MjA2NDAwMCwiZXhwIjoxNzcyMDY0
|
||
OTAwLCJqdGkiOiI1NTBlODQwMC1lMjliLTQxZDQtYTcxNi00NDY2NTU0NDAwMDgi
|
||
LCJ0YXNrIjp7InB1cnBvc2UiOiJiYWRfZGVwdGgifSwiY2FwIjpbeyJhY3Rpb24i
|
||
OiJyZWFkLmRhdGEifV0sImRlbCI6eyJkZXB0aCI6MywibWF4X2RlcHRoIjoyLCJj
|
||
aGFpbiI6W3siZGVsZWdhdG9yIjoiYSIsImp0aSI6ImoxIiwic2lnIjoic2lnMSJ9
|
||
LHsiZGVsZWdhdG9yIjoiYiIsImp0aSI6ImoyIiwic2lnIjoic2lnMiJ9LHsiZGVs
|
||
ZWdhdG9yIjoiYyIsImp0aSI6ImozIiwic2lnIjoic2lnMyJ9XX19.bhZ7ZaXG6GN
|
||
q4vqquQPcxImFlu50rV8Ae16D06N_X9bRCu9pCiMcY2LTK9XRYWcKlRjUyBRVNJX
|
||
02bFXJ5wGAA
|
||
|
||
Expected result: Reject. del.depth (3) exceeds del.max_depth (2).
|
||
|
||
B.7. Invalid: capability escalation in delegated mandate
|
||
|
||
Expected result: Reject. The delegated cap (max_records=100) is not
|
||
a subset of the parent cap (max_records=10); privilege reduction is
|
||
violated. This vector is a delegation-creation check; no token is
|
||
issued.
|
||
|
||
B.8. Invalid: exec_act not present in cap
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "sub-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 56]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": "agent-subject",
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440009",
|
||
"task": {
|
||
"purpose": "bad_exec"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data"
|
||
}
|
||
],
|
||
"exec_act": "delete.everything",
|
||
"pred": [],
|
||
"exec_ts": 1772064100,
|
||
"status": "completed"
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJzdWIta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjoiYWdlbnQtc3ViamVjdCIsImlhdCI6MTc3MjA2NDAwMCwiZXhwIjoxNzcyMDY0
|
||
OTAwLCJqdGkiOiI1NTBlODQwMC1lMjliLTQxZDQtYTcxNi00NDY2NTU0NDAwMDki
|
||
LCJ0YXNrIjp7InB1cnBvc2UiOiJiYWRfZXhlYyJ9LCJjYXAiOlt7ImFjdGlvbiI6
|
||
InJlYWQuZGF0YSJ9XSwiZXhlY19hY3QiOiJkZWxldGUuZXZlcnl0aGluZyIsInBy
|
||
ZWQiOltdLCJleGVjX3RzIjoxNzcyMDY0MTAwLCJzdGF0dXMiOiJjb21wbGV0ZWQi
|
||
fQ.AI-K0abyWHyAUTxIUS22kqhmSdgfOVyLMHaOm6vauEd3YpoRQ8vdzJ2Oblk07
|
||
qyXwR5pAlDewYOwCJTSmIK0Cg
|
||
|
||
Expected result: Reject. exec_act "delete.everything" does not match
|
||
any cap.action.
|
||
|
||
B.9. Invalid: DAG cycle (pred references own jti)
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "sub-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 57]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": "agent-subject",
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-44665544000a",
|
||
"task": {
|
||
"purpose": "cycle_test"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data"
|
||
}
|
||
],
|
||
"exec_act": "read.data",
|
||
"pred": [
|
||
"550e8400-e29b-41d4-a716-44665544000a"
|
||
],
|
||
"exec_ts": 1772064100,
|
||
"status": "completed"
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJzdWIta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjoiYWdlbnQtc3ViamVjdCIsImlhdCI6MTc3MjA2NDAwMCwiZXhwIjoxNzcyMDY0
|
||
OTAwLCJqdGkiOiI1NTBlODQwMC1lMjliLTQxZDQtYTcxNi00NDY2NTU0NDAwMGEi
|
||
LCJ0YXNrIjp7InB1cnBvc2UiOiJjeWNsZV90ZXN0In0sImNhcCI6W3siYWN0aW9u
|
||
IjoicmVhZC5kYXRhIn1dLCJleGVjX2FjdCI6InJlYWQuZGF0YSIsInByZWQiOlsi
|
||
NTUwZTg0MDAtZTI5Yi00MWQ0LWE3MTYtNDQ2NjU1NDQwMDBhIl0sImV4ZWNfdHMi
|
||
OjE3NzIwNjQxMDAsInN0YXR1cyI6ImNvbXBsZXRlZCJ9.9V4Pd5QoKBXLnBCAJne
|
||
PR_QArbIdLAEYFkM0az0ATr_A8BqjQdCQm-zDxExszLBnSdVclHo1Ns25FSpzrDj
|
||
VDg
|
||
|
||
Expected result: Reject. pred references the record's own jti,
|
||
forming a cycle.
|
||
|
||
B.10. Invalid: missing predecessor task in DAG
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "sub-key"
|
||
}
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 58]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
JWT Claims:
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": "agent-subject",
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-44665544000b",
|
||
"task": {
|
||
"purpose": "missing_parent"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data"
|
||
}
|
||
],
|
||
"exec_act": "read.data",
|
||
"pred": [
|
||
"nonexistent-parent-jti"
|
||
],
|
||
"exec_ts": 1772064100,
|
||
"status": "completed"
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJzdWIta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjoiYWdlbnQtc3ViamVjdCIsImlhdCI6MTc3MjA2NDAwMCwiZXhwIjoxNzcyMDY0
|
||
OTAwLCJqdGkiOiI1NTBlODQwMC1lMjliLTQxZDQtYTcxNi00NDY2NTU0NDAwMGIi
|
||
LCJ0YXNrIjp7InB1cnBvc2UiOiJtaXNzaW5nX3BhcmVudCJ9LCJjYXAiOlt7ImFj
|
||
dGlvbiI6InJlYWQuZGF0YSJ9XSwiZXhlY19hY3QiOiJyZWFkLmRhdGEiLCJwcmVk
|
||
IjpbIm5vbmV4aXN0ZW50LXBhcmVudC1qdGkiXSwiZXhlY190cyI6MTc3MjA2NDEw
|
||
MCwic3RhdHVzIjoiY29tcGxldGVkIn0.PSxajLuiL_b2cAZT2Eab5UR-nZDMs2BE
|
||
jEkhzeId8vQzYkldQb9h5xrvvRD9lsjglzda4wscpU-IoW4m8Kw4Cw
|
||
|
||
Expected result: Reject. pred references a jti that is not a
|
||
previously verified task.
|
||
|
||
B.11. Invalid: tampered payload
|
||
|
||
JOSE Header:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 59]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "iss-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": [
|
||
"agent-subject",
|
||
"https://ledger.example.com"
|
||
],
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440001",
|
||
"task": {
|
||
"purpose": "validate_data",
|
||
"tata_sensitivity": "restricted"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data",
|
||
"constraints": {
|
||
"max_records": 10
|
||
}
|
||
},
|
||
{
|
||
"action": "write.result"
|
||
}
|
||
],
|
||
"wid": "a0b1c2d3-e4f5-6789-abcd-ef0123456789",
|
||
"del": {
|
||
"depth": 0,
|
||
"max_depth": 2,
|
||
"chain": []
|
||
}
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 60]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJpc3Mta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjpbImFnZW50LXN1YmplY3QiLCJodHRwczovL2xlZGdlci5leGFtcGxlLmNvbSJd
|
||
LCJpYXQiOjE3NzIwNjQwMDAsImV4cCI6MTc3MjA2NDkwMCwianRpIjoiNTUwZTg0
|
||
MDAtZTI5Yi00MWQ0LWE3MTYtNDQ2NjU1NDQwMDAxIiwidGFzayI6eyJwdXJwb3Nl
|
||
IjoidmFsaWRhdGVfZGF0YSIsInRhdGFfc2Vuc2l0aXZpdHkiOiJyZXN0cmljdGVk
|
||
In0sImNhcCI6W3siYWN0aW9uIjoicmVhZC5kYXRhIiwiY29uc3RyYWludHMiOnsi
|
||
bWF4X3JlY29yZHMiOjEwfX0seyJhY3Rpb24iOiJ3cml0ZS5yZXN1bHQifV0sIndp
|
||
ZCI6ImEwYjFjMmQzLWU0ZjUtNjc4OS1hYmNkLWVmMDEyMzQ1Njc4OSIsImRlbCI6
|
||
eyJkZXB0aCI6MCwibWF4X2RlcHRoIjoyLCJjaGFpbiI6W119fQ._nVgyp4X0zYvy
|
||
ylbyBgE_CWKAVdEMFgHjHIUkhxEsr83PQw_rzxNryDd179_KdkCo_kxWDbfmEQV-
|
||
JA1-pknBA
|
||
|
||
Expected result: Reject. The signature does not verify; one byte of
|
||
the claims segment was altered after signing.
|
||
|
||
B.12. Invalid: expired token
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "iss-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": "agent-subject",
|
||
"iat": 1772060400,
|
||
"exp": 1772061300,
|
||
"jti": "550e8400-e29b-41d4-a716-44665544000c",
|
||
"task": {
|
||
"purpose": "expired_test"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data"
|
||
}
|
||
]
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 61]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJpc3Mta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjoiYWdlbnQtc3ViamVjdCIsImlhdCI6MTc3MjA2MDQwMCwiZXhwIjoxNzcyMDYx
|
||
MzAwLCJqdGkiOiI1NTBlODQwMC1lMjliLTQxZDQtYTcxNi00NDY2NTU0NDAwMGMi
|
||
LCJ0YXNrIjp7InB1cnBvc2UiOiJleHBpcmVkX3Rlc3QifSwiY2FwIjpbeyJhY3Rp
|
||
b24iOiJyZWFkLmRhdGEifV19.mK6-ML3hkOlAVvHeG5PPnvr3do9KT-1g4OISjlB
|
||
WrcHac-JPWnzOSZmMiESIKA6mXNSYVxnTDLZyFbAPglrCAQ
|
||
|
||
Expected result: Reject. exp is in the past (expired 45 minutes
|
||
before the verification time).
|
||
|
||
B.13. Invalid: audience mismatch
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "iss-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "wrong-agent",
|
||
"aud": "wrong-agent",
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-44665544000d",
|
||
"task": {
|
||
"purpose": "wrong_aud_test"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data"
|
||
}
|
||
]
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 62]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJpc3Mta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJ3cm9uZy1hZ2VudCIsImF1ZCI6
|
||
Indyb25nLWFnZW50IiwiaWF0IjoxNzcyMDY0MDAwLCJleHAiOjE3NzIwNjQ5MDAs
|
||
Imp0aSI6IjU1MGU4NDAwLWUyOWItNDFkNC1hNzE2LTQ0NjY1NTQ0MDAwZCIsInRh
|
||
c2siOnsicHVycG9zZSI6Indyb25nX2F1ZF90ZXN0In0sImNhcCI6W3siYWN0aW9u
|
||
IjoicmVhZC5kYXRhIn1dfQ.8vP0564UjixScto2vo0MX5wt5TX_dP9ilDB8aPEpl
|
||
WnOovQgQUHywL0_BqSaqgM7NrtjGnITmVoJ6RtUrjV8CA
|
||
|
||
Expected result: Reject. aud does not include the verifier identity.
|
||
|
||
B.14. Invalid: Phase 2 record signed by wrong key
|
||
|
||
JOSE Header:
|
||
|
||
{
|
||
"alg": "EdDSA",
|
||
"typ": "act+jwt",
|
||
"kid": "sub-key"
|
||
}
|
||
|
||
JWT Claims:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 63]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
{
|
||
"iss": "agent-issuer",
|
||
"sub": "agent-subject",
|
||
"aud": [
|
||
"agent-subject",
|
||
"https://ledger.example.com"
|
||
],
|
||
"iat": 1772064000,
|
||
"exp": 1772064900,
|
||
"jti": "550e8400-e29b-41d4-a716-446655440001",
|
||
"task": {
|
||
"purpose": "validate_data",
|
||
"data_sensitivity": "restricted"
|
||
},
|
||
"cap": [
|
||
{
|
||
"action": "read.data",
|
||
"constraints": {
|
||
"max_records": 10
|
||
}
|
||
},
|
||
{
|
||
"action": "write.result"
|
||
}
|
||
],
|
||
"exec_act": "read.data",
|
||
"pred": [],
|
||
"exec_ts": 1772064300,
|
||
"status": "completed",
|
||
"wid": "a0b1c2d3-e4f5-6789-abcd-ef0123456789",
|
||
"del": {
|
||
"depth": 0,
|
||
"max_depth": 2,
|
||
"chain": []
|
||
}
|
||
}
|
||
|
||
JWS Compact Serialization:
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 64]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
eyJhbGciOiJFZERTQSIsInR5cCI6ImFjdCtqd3QiLCJraWQiOiJzdWIta2V5In0.
|
||
eyJpc3MiOiJhZ2VudC1pc3N1ZXIiLCJzdWIiOiJhZ2VudC1zdWJqZWN0IiwiYXVk
|
||
IjpbImFnZW50LXN1YmplY3QiLCJodHRwczovL2xlZGdlci5leGFtcGxlLmNvbSJd
|
||
LCJpYXQiOjE3NzIwNjQwMDAsImV4cCI6MTc3MjA2NDkwMCwianRpIjoiNTUwZTg0
|
||
MDAtZTI5Yi00MWQ0LWE3MTYtNDQ2NjU1NDQwMDAxIiwidGFzayI6eyJwdXJwb3Nl
|
||
IjoidmFsaWRhdGVfZGF0YSIsImRhdGFfc2Vuc2l0aXZpdHkiOiJyZXN0cmljdGVk
|
||
In0sImNhcCI6W3siYWN0aW9uIjoicmVhZC5kYXRhIiwiY29uc3RyYWludHMiOnsi
|
||
bWF4X3JlY29yZHMiOjEwfX0seyJhY3Rpb24iOiJ3cml0ZS5yZXN1bHQifV0sImV4
|
||
ZWNfYWN0IjoicmVhZC5kYXRhIiwicHJlZCI6W10sImV4ZWNfdHMiOjE3NzIwNjQz
|
||
MDAsInN0YXR1cyI6ImNvbXBsZXRlZCIsIndpZCI6ImEwYjFjMmQzLWU0ZjUtNjc4
|
||
OS1hYmNkLWVmMDEyMzQ1Njc4OSIsImRlbCI6eyJkZXB0aCI6MCwibWF4X2RlcHRo
|
||
IjoyLCJjaGFpbiI6W119fQ.rTp6oHlLzG32Ex6P08rAafhmjzRdwQTjwgU1Cod1a
|
||
kFy3x5KpaX5fkfeCiK5i0D6HAtwUYR61_HlBWCcJj5_BA
|
||
|
||
Expected result: Reject. The Phase 2 record claims kid "sub-key" but
|
||
was signed with the issuer's private key; the signature does not
|
||
verify.
|
||
|
||
B.15. Invalid: unsigned token (alg "none")
|
||
|
||
JWS Compact Serialization:
|
||
|
||
eyJhbGciOiJub25lIiwidHlwIjoiYWN0K2p3dCIsImtpZCI6ImsifQ.eyJpc3MiO
|
||
iJhIiwic3ViIjoiYiJ9.
|
||
|
||
Expected result: Reject. The JOSE header alg is "none"; unsigned
|
||
tokens MUST NOT be accepted.
|
||
|
||
Appendix C: Deployment Scenarios
|
||
|
||
C.1. Minimal Deployment (Zero Infrastructure)
|
||
|
||
Two organizations exchange pre-shared public keys via secure email.
|
||
Each agent signs Phase 1 mandates and Phase 2 records with its
|
||
Ed25519 key. No ledger, no external services. Suitable for
|
||
development and low-risk workflows.
|
||
|
||
Limitation: No non-equivocation (Section 11.5).
|
||
|
||
C.2. Regulated Deployment with Hash-Chained Ledger
|
||
|
||
Phase 2 ACTs are submitted to a shared append-only ledger with hash-
|
||
chaining. Each recorded ACT extends a cryptographic chain, providing
|
||
tamper evidence for each ACT and the chain as a whole. The ledger is
|
||
shared between all regulated parties participating in the workflow.
|
||
Suitable for DORA compliance.
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 65]
|
||
|
||
Internet-Draft ACT May 2026
|
||
|
||
|
||
C.3. High-Assurance Cross-Organizational Deployment
|
||
|
||
Phase 2 ACTs are anchored to a SCITT Transparency Service. SCITT
|
||
receipts are attached to the audit record as non-equivocation proofs.
|
||
DID-based agent identities (Tier 3) enable self-sovereign key
|
||
management without shared CA infrastructure.
|
||
|
||
C.4. WIMSE Environment Integration
|
||
|
||
In environments where WIMSE is already deployed, ACT-Mandate and ACT-
|
||
Record headers are carried alongside the WIMSE Workload-Identity
|
||
header. The ECT and ACT serve different purposes: the ECT records
|
||
workload-level execution in WIMSE terms; the ACT records the
|
||
authorization provenance and capability constraints that governed the
|
||
action.
|
||
|
||
Acknowledgments
|
||
|
||
The author thanks the IETF WIMSE, OAuth, and SCITT working groups for
|
||
foundational work on workload identity, delegated authorization, and
|
||
transparent supply chain records that informs this specification.
|
||
|
||
Author's Address
|
||
|
||
Christian Nennemann
|
||
Independent Researcher
|
||
Email: ietf@nennemann.de
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
Nennemann Expires 21 November 2026 [Page 66]
|