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AI Agent Authentication and Authorization
draft-klrc-aiagent-auth-01

Document Type Active Internet-Draft (individual)
Authors Pieter Kasselman , Jeff Lombardo , Yaroslav Rosomakho , Brian Campbell , Nick Steele
Last updated 2026-03-30
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draft-klrc-aiagent-auth-01
Network Working Group                                       P. Kasselman
Internet-Draft                                          Defakto Security
Intended status: Informational                               J. Lombardo
Expires: 1 October 2026                                              AWS
                                                            Y. Rosomakho
                                                                 Zscaler
                                                             B. Campbell
                                                           Ping Identity
                                                               N. Steele
                                                                 Open AI
                                                           30 March 2026

               AI Agent Authentication and Authorization
                       draft-klrc-aiagent-auth-01

Abstract

   This document proposes a model for authentication and authorization
   of AI agent interactions.  It leverages existing standards such as
   the Workload Identity in Multi-System Environments (WIMSE)
   architecture and OAuth 2.0 family of specifications.  Rather than
   defining new protocols, this document describes how existing and
   widely deployed standards can be applied or extended to establish
   agent authentication and authorization.  By doing so, it aims to
   provide a framework within which to use existing standards, identify
   gaps and guide future standardization efforts for agent
   authentication and authorization.

About This Document

   This note is to be removed before publishing as an RFC.

   The latest revision of this draft can be found at
   https://PieterKas.github.io/agent2agent-auth-framework/draft-klrc-
   aiagent-auth.html.  Status information for this document may be found
   at https://datatracker.ietf.org/doc/draft-klrc-aiagent-auth/.

   Source for this draft and an issue tracker can be found at
   https://github.com/PieterKas/agent2agent-auth-framework.

Status of This Memo

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

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   Copyright (c) 2026 IETF Trust and the persons identified as the
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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Conventions and Definitions . . . . . . . . . . . . . . . . .   4
   3.  Agents are workloads  . . . . . . . . . . . . . . . . . . . .   4
   4.  Agent Identity Management System  . . . . . . . . . . . . . .   6
   5.  Agent Identifier  . . . . . . . . . . . . . . . . . . . . . .   7
   6.  Agent Credentials . . . . . . . . . . . . . . . . . . . . . .   8
   7.  Agent Attestation . . . . . . . . . . . . . . . . . . . . . .   9
   8.  Agent Credential Provisioning . . . . . . . . . . . . . . . .   9
   9.  Agent Authentication  . . . . . . . . . . . . . . . . . . . .  10
     9.1.  Transport Layer Authentication  . . . . . . . . . . . . .  10
       9.1.1.  Limitations . . . . . . . . . . . . . . . . . . . . .  11
     9.2.  Application Layer Authentication  . . . . . . . . . . . .  11
       9.2.1.  WIMSE Proof Tokens (WPTs) . . . . . . . . . . . . . .  11
       9.2.2.  HTTP Message Signatures . . . . . . . . . . . . . . .  12
       9.2.3.  Limitations . . . . . . . . . . . . . . . . . . . . .  12
   10. Agent Authorization . . . . . . . . . . . . . . . . . . . . .  13
     10.1.  Leverage OAuth 2.0 as a Delegation Authorization
            Framework  . . . . . . . . . . . . . . . . . . . . . . .  13
     10.2.  Use of OAuth 2.0 Access Tokens . . . . . . . . . . . . .  13
     10.3.  Obtaining an OAuth 2.0 Access Token  . . . . . . . . . .  14

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       10.3.1.  User Delegates Authorization . . . . . . . . . . . .  14
       10.3.2.  Agent Obtains Own Authorization  . . . . . . . . . .  14
       10.3.3.  Agents Accessed by Systems or Other Agents . . . . .  15
       10.3.4.  OAuth 2.0 Security Best Practices  . . . . . . . . .  15
     10.4.  Risk Reduction with Transaction Tokens . . . . . . . . .  15
     10.5.  Cross Domain Access  . . . . . . . . . . . . . . . . . .  16
     10.6.  Human in the Loop  . . . . . . . . . . . . . . . . . . .  16
     10.7.  Tool-to-Service Access . . . . . . . . . . . . . . . . .  17
     10.8.  Privacy Considerations {privacy-considerations}  . . . .  18
     10.9.  OAuth 2.0 Discovery in Dynamic Environments  . . . . . .  18
       10.9.1.  Authorization Server Capability Discovery  . . . . .  18
       10.9.2.  Protected Resource Capability Discovery  . . . . . .  19
       10.9.3.  Client Capability Discovery  . . . . . . . . . . . .  19
   11. Agent Monitoring, Observability and Remediation . . . . . . .  19
   12. Agent Authentication and Authorization Policy . . . . . . . .  21
   13. Agent Compliance  . . . . . . . . . . . . . . . . . . . . . .  21
   14. Security Considerations . . . . . . . . . . . . . . . . . . .  21
   15. Privacy Considerations  . . . . . . . . . . . . . . . . . . .  21
   16. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  21
   17. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  21
   18. Normative References  . . . . . . . . . . . . . . . . . . . .  22
   Appendix A.  Document History . . . . . . . . . . . . . . . . . .  25
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  26

1.  Introduction

   The rapid emergence of AI agents as autonomous workloads has sparked
   considerable innovation in authentication and authorization
   approaches.  However, many of these efforts develop solutions in
   isolation, often reinventing existing mechanisms unaware of
   applicable prior art.  This fragmentation risks creating incompatible
   implementations, duplicated development effort, and missed
   opportunities to leverage decades of established identity and
   authorization standards.

   This document aims to help close that gap by providing a
   comprehensive model demonstrating how existing, well-established
   standards and some emergent specifications can be composed and
   applied to solve agent authentication and authorization challenges.
   Rather than proposing new protocols, this work focuses on integrating
   proven standards into a coherent framework tailored to the specific
   requirements of AI agent workloads.

   By doing so, this document serves two complementary goals:

   1.  *Consolidation of prior art*: It establishes a baseline by
       showing how existing standards address the core identity,
       authentication, authorization, monitoring and observability needs

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       of agent-based systems.  Implementers and standards developers
       can reference this framework to avoid redundant work and ensure
       interoperability.

   2.  *Foundation for future work*: As the agent ecosystem matures,
       having such a framework aids in identifying gaps and clarifies
       where extensions or profiles of existing standards are needed.
       This provides a foundation for more focused standardization
       efforts in areas needing novel work rather than variations of
       existing approaches.

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.

3.  Agents are workloads

   An Agent is a workload that iteratively interacts with a Large
   Language Model (LLM) and a set of Tools, Services and Resources.  An
   agent performs its operations until a terminating condition,
   determined either by the LLM or by the agent's internal logic, is
   reached.  It may receive input from a user, or act autonomously.
   Figure 1 shows a conceptual model of the AI Agent as a workload and
   illustrates the high-level interaction model between the User or
   System, the AI Agent, the Large Language Model (LLM), Tools,
   Services, and Resources.

   In this document, Tools, Services, and Resources are treated as a
   single category of external endpoints that an agent invokes or
   interacts with to complete a task.  Communication within or between
   Tools, Services, and Resources is out of scope.

                   +----------------+
                   | Large Language |
                   |   Model (LLM)  |
                   +----------------+
                         ^   |
                        (2) (3)
                         |   V
   +--------+       +------------+       +-----------+
   |  User  |--(1)->|  AI Agent  |--(4)->|   Tools   |
   |   or   |       | (workload) |       | Services  |
   | System |<-(6)--|            |<-(5)--| Resources |
   +--------+       +------------+       +-----------+

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                      Figure 1: AI Agent as a Workload

   1.  Optional: The User or System (e.g. a batch job or another Agent)
       provides an initial request or instruction to the AI Agent.

   2.  The AI Agent provides the available context to the LLM.  Context
       is implementation, and deployment, specific and may include User
       or System input, system prompts, Tool descriptions, prior Tool,
       Service and Resource outputs, and other relevant state.

   3.  The LLM returns output to the AI Agent facilitating selection of
       Tools, Services or Resources to invoke.

   4.  The AI Agent invokes one or more external endpoints of selected
       Tools, Services or Resources.  A Tool endpoint may itself be
       implemented by another AI agent.

   5.  The external endpoint of the Tools, Services or Resources returns
       a result of the operation to the AI Agent, which may send the
       information as additional context to the Large Language Model,
       repeating steps 2-5 until the exit condition is reached and the
       task is completed.

   6.  Optional: Once the exit condition is reached in step 5, the AI
       Agent may return a response to the User or System.  The AI Agent
       may also return intermediate results or request additional input.

   As shown in Figure 1, the AI agent is a workload that needs an
   identifier and credentials so it can be authenticated by the Tools,
   Services, Resources, Large Language Model, System and the User (via
   the underlying operating system or platform, similar to existing
   applications and services).  Once authenticated, these parties
   determine if the AI Agent is authorized to access the requested Large
   Language Model, Tools, Services or Resources.  If the AI Agent is
   acting on behalf of a User or System, the User or System needs to
   delegate authority to the AI Agent, and the User or System context is
   preserved and used as input to authorization decisions and recorded
   in audit trails.

   This document describes how AI Agents should leverage existing
   standards defined by SPIFFE [SPIFFE], WIMSE, OAuth and OpenID SSF
   [SSF].

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4.  Agent Identity Management System

   This document defines the term Agent Identity Management System
   (AIMS) as a conceptual model describing the set of functions required
   to establish, maintain, and evaluate the identity and permissions of
   an agent workload.  AIMS does not refer to a single product,
   protocol, or deployment architecture.  AIMS may be implemented by one
   component or distributed across multiple systems (such as identity
   providers, attestation services, authorization servers, policy
   engines, and runtime enforcement points).

   An Agent Identity Management System ensures that the right Agent has
   access to the right resources and tools at the right time for the
   right reason.  An Agent identity management system depends on the
   following components to achieve its goals:

   *  *Agent Identifiers:* Unique identifier assigned to every Agent.

   *  *Agent Credentials:* Cryptographic binding between the Agent
      Identifier and attributes of the Agent.

   *  *Agent Attestation:* Mechanisms for determining and assigning the
      identifier and issue credentials based on measurements of the
      Agent's environment.

   *  *Agent Credential Provisioning:* The mechanism for provisioning
      credentials to the agent at runtime.

   *  *Agent Authentication:* Protocols and mechanisms used by the Agent
      to authenticate itself to Large Language Models or Tools (resource
      or server) in the system.

   *  *Agent Authorization:* Protocols and systems used to determine if
      an Agent is allowed to access a Large Language Model or Tool
      (resource or server).

   *  *Agent Observability and Remediation:* Protocols and mechanisms to
      dynamically modify the authorization decisions based on observed
      behavior and system state.

   *  *Agent Authentication and Authorization Policy:* The configuration
      and rules for each of the Agent Identity Management System.

   *  *Agent Compliance:* Measurement of the state and functioning of
      the system against the stated policies.

   The components form a logical stack in which higher layers depend on
   guarantees provided by lower layers, as illustrated in Figure 2.

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   +--------------+----------------------------------+-----------------+
   |    Policy    |     Monitoring, Observability    |    Compliance   |
   |              |          & Remediation           |                 |
   |              +----------------------------------+                 |
   |              |          Authorization           |                 |
   |              +----------------------------------+                 |
   |              |          Authentication          |                 |
   |              +----------------------------------+                 |
   |              |          Provisioning            |                 |
   |              +----------------------------------+                 |
   |              |           Attestation            |                 |
   |              +----------------------------------+                 |
   |              |           Credentials            |                 |
   |              +----------------------------------+                 |
   |              |           Identifier             |                 |
   +--------------+----------------------------------+-----------------+

                 Figure 2: Agent Identity Management System

5.  Agent Identifier

   Agents MUST be uniquely identified in order to support
   authentication, authorization, auditing, and delegation.

   The Workload Identity in Multi-System Environments (WIMSE) identifier
   as defined by [WIMSE-ID] is the primary identifier for agents in this
   framework.

   A WIMSE identifier is a URI that uniquely identifies a workload
   within a trust domain.  Authorization decisions, delegation
   semantics, and audit records rely on this identifier remaining stable
   for the lifetime of the workload identity.

   The Secure Production Identity Framework for Everyone ([SPIFFE])
   identifier is a widely deployed and operationally mature
   implementation of the WIMSE identifier model.  A SPIFFE identifier
   ([SPIFFE-ID]) is a URI in the form of spiffe://<trust-domain>/<path>
   that uniquely identifies a workload within a trust domain.

   An agent participating in this framework MUST be assigned exactly one
   WIMSE identifier, which MAY be a SPIFFE ID.

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6.  Agent Credentials

   Agents MUST possess credentials that provide a cryptographic binding
   to the agent identifier.  These credentials are considered primary
   credentials that are provisioned at runtime.  An identifier alone is
   insufficient unless it can be verified to be controlled by the
   communicating agent through a cryptographic binding.

   WIMSE credentials ([WIMSE-CRED]) are defined as a profile of X.509
   certificates and Workload Identity Tokens (WITs), while SPIFFE
   defines SPIFFE Verified ID (SVID) profiles of JSON Web Token (JWT-
   SVID), X.509 certificates (X.509-SVID) and WIMSE Workload Identity
   Tokens (WIT-SVID).  SPIFFE SVID credentials are compatible with WIMSE
   defined credentials.  The choice of an appropriate format depends on
   the trust model and integration requirements.

   Agent credentials SHOULD be short-lived to minimize the risk of
   credential theft, MUST include an explicit expiration time after
   which it is no longer accepted, and MAY carry additional attributes
   relevant to the agent (for example trust domain, attestation
   evidence, or workload metadata).

   Deployments can improve the assurance of agent identity by protecting
   private keys using hardware-backed or isolated cryptographic storage
   such as TPMs, secure enclaves, or platform security modules when such
   capabilities are available.  These mechanisms reduce key exfiltration
   risk but are not required for interoperability.

   In some cases, agents MAY need secondary credentials to access a
   proprietary or legacy environment that is not compatible with the
   X.509, JWT or WIT it is provisioned with.  In these cases an agent
   MAY exchange their primary credentials through a credential exchange
   mechanisms (e.g., OAuth 2.0 Token Exchange [OAUTH-TOKEN-EXCHANGE],
   Transaction Tokens [OAUTH-TXN-TOKENS] or Workload Identity
   Federation).  This allows an agent to obtain a credential targeted to
   a specific environment by leveraging the primary credential in its
   possession.

   *Note*: Static API keys are an antipattern for agent identity.  They
   are bearer artifacts that are not cryptographically bound, do not
   convey identity, are typically long-lived and are operationally
   difficult to rotate, making them unsuitable for secure agent
   authentication or authorization.

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7.  Agent Attestation

   Agent attestation is the identity-proofing mechanism for AI agents.
   Just as humans rely on identity proofing during account creation or
   credential issuance, agents require a means to demonstrate what they
   are, how they were instantiated, and under what conditions they are
   operating.  Attestation evidence feeds into the credential issuance
   process and determines whether a credential is issued, the type of
   credential issued and the contents of the credential.

   Multiple attestation mechanisms exist, and the appropriate choice is
   deployment and risk specific.  These mechanisms may include hardware-
   based attestations (e.g., TEE evidence), software integrity
   measurements, supply-chain provenance, platform and orchestration-
   layer attestations, or operator assertions to name a few.  Depending
   on the risk involved, a single attestation may be sufficient, or, in
   higher risk scenarios, multi-attestation may be required.

   There are numerous systems that perform some form of attestation, any
   of which can contribute to establishing agent identity.  For example,
   SPIFFE implementations can attest workloads using platform and
   environment specific mechanisms.  At a high level, an attesting
   component gathers workload and execution context signals (such as
   where the workload is running and relevant platform identity
   attributes), presents those signals for verification to an issuer,
   and, as long as verification succeeds, binds the workload to a SPIFFE
   identifier and issues credentials (such as SVID) for subsequent
   authentication and authorization.

   An agent identity management system may incorporate multiple
   attestation mechanisms and implementations to collect evidence and
   supply it to credential provisioning components.  The selection of
   mechanisms depends on deployment constraints (such as the underlying
   platform and available identity signals) and the desired level of
   trust assurance.

8.  Agent Credential Provisioning

   Agent credential provisioning refers to the runtime issuance,
   renewal, lifecycle state and rotation of the credentials an agent
   uses to authenticate and authorize itself to other agents.  Agents
   may be provisioned with one or more credential types as described in
   Section 6.  Unlike static secrets, agent credentials are provisioned
   dynamically and are intentionally short-lived, eliminating the
   operational burden of manual expiration management and reducing the
   impact of credential compromise.  Agent credential provisioning must
   operate autonomously, scale to high-churn environments, and integrate
   closely with the attestation mechanisms that establish trust in the

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   agent at each issuance or rotation event.

   Agent credential provisioning typically includes two phases:

   1.  *Initial Provisioning*: The process by which an agent first
       acquires a credential bound to its identity.  This often occurs
       immediately after deployment or instantiation and is based on
       verified properties of the agent (e.g., deployment context,
       attestation evidence, or orchestration metadata).

   2.  *Rotation/Renewal*: The automatic refresh of short-lived
       credentials before expiration.  Continuous rotation ensures that
       credentials remain valid only for the minimum necessary time and
       that authorization state reflects current operational conditions.

   The use of short-lived credentials provides a significant improvement
   in the risk profile and risk of credential exposure.  It provides an
   alternative to explicit revocation mechanisms and simplifies
   lifecycle management in large, automated environments while removing
   the risks of downtime as a result of credential expiry.

   Deployed frameworks such as [SPIFFE] provide proven mechanisms for
   automated, short-lived credential provisioning at runtime.  In
   addition to issuing short-lived credentials, [SPIFFE] also provisions
   ephemeral cryptographic key material bound to each credential,
   further reducing the risks associated with compromising long-lived
   keys.

9.  Agent Authentication

   Agents may authenticate using a variety of mechanisms, depending on
   the credentials they possess, the protocols supported in the
   deployment environment, and the risk profile of the application.  As
   described in the WIMSE Architecture [WIMSE-ARCH], authentication can
   occur at either the transport layer or the application layer, and
   many deployments rely on a combination of both.

9.1.  Transport Layer Authentication

   Transport-layer authentication establishes trust during the
   establishment of a secure transport channel.  The most common
   mechanism used by agents is mutually-authenticated TLS (mTLS), in
   which both endpoints present X.509-based credentials and perform a
   bidirectional certificate exchange as part of the TLS negotiation.
   When paired with short-lived workload identities, such as those
   issued by SPIFFE or WIMSE, mTLS provides strong channel binding and
   cryptographic proof of control over the agent’s private key.

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   mTLS is particularly well-suited for environments where transport-
   level protection, peer authentication, and ephemeral workload
   identity are jointly required.  It also simplifies authorization
   decisions by enabling agents to associate application-layer requests
   with an authenticated transport identity.  One example of this is the
   use of mTLS in service mesh architectures such as Istio or LinkerD.

9.1.1.  Limitations

   There are scenarios where transport-layer authentication is not
   desirable or cannot be relied upon.  In architectures involving
   intermediaries, such as proxies, API gateways, service meshes, load
   balancers, or protocol translators, TLS sessions are often terminated
   and re-established, breaking the end-to-end continuity of transport-
   layer identity.  Similarly, some deployment models (such as
   serverless platforms, multi-tenant edge environments, or cross-domain
   topologies) may obscure or abstract identity presented at the
   transport layer, making it difficult to bind application-layer
   actions to a credential presented at the transport layer.  In these
   cases, application-layer authentication provides a more robust and
   portable mechanism for expressing agent identity and conveying
   attestation or policy-relevant attributes.

9.2.  Application Layer Authentication

   Application-layer authentication allows agents to authenticate
   independently of the underlying transport.  This enables end-to-end
   identity preservation even when requests traverse proxies, load
   balancers, or protocol translation layers.

   The WIMSE working group defines WIMSE Proof Tokens and HTTP Message
   Signatures as authentication mechanisms that may be used by agents.

9.2.1.  WIMSE Proof Tokens (WPTs)

   WIMSE Workload Proof Tokens (WPTs, [WIMSE-WPT]) are a protocol-
   independent, application-layer mechanism for proving possession of
   the private key associated with a Workload Identity Token (WIT).
   WPTs are generated by the agent, using the private key matching the
   public key in the WIT.  A WPT is defined as a signed JSON Web Token
   (JWT) that binds an agent’s authentication to a specific message
   context, for example, an HTTP request, thereby providing proof of
   possession rather than relying on bearer semantics.

   WPTs are designed to work alongside WITs [WIMSE-CRED] and are
   typically short-lived to reduce the window for replay attacks.  They
   carry claims such as audience (aud), expiration (exp), a unique token
   identifier (jti), and a hash of the associated WIT (wth).  A WPT may

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   also include hashes of other related tokens (e.g., a Transaction
   Token) to bind the authentication contexts to specific transaction or
   authorizations details.

   Although the draft currently defines a protocol binding for HTTP (via
   a Workload-Proof-Token header), the core format is protocol-agnostic,
   making it applicable to other protocols.  Its JWT structure and
   claims model allow WPTs to be bound to different protocols and
   transports, including asynchronous or non-HTTP messaging systems such
   as Kafka and gRPC, or other future protocol bindings.  This design
   enables receiving systems to verify identity, key possession, and
   message binding at the application layer even in environments where
   transport-layer identity (e.g., mutual TLS) is insufficient or
   unavailable.

9.2.2.  HTTP Message Signatures

   The WIMSE Workload-to-Workload Authentication with HTTP Signatures
   specification [WIMSE-HTTPSIG] defines an application-layer
   authentication profile built on the HTTP Message Signatures standard
   [HTTP-SIG].  It is one of the mechanisms WIMSE defines for
   authenticating workloads in HTTP-based interactions where transport-
   layer protections may be insufficient or unavailable.  The protocol
   combines a workload's Workload Identity Token (WIT) (which binds the
   agent's identity to a public key) with HTTP Message Signatures (using
   the corresponding private key), thereby providing proof of possession
   and message integrity for individual HTTP requests and responses.
   This approach ensures end-to-end authentication and integrity even
   when traffic traverses intermediaries such as TLS proxies or load
   balancers that break transport-layer identity continuity.  The
   profile mandates signing of some request components (e.g., method,
   request-target, content digest, and the WIT itself) and supports
   optional response signing.  Note that @request-target covers only the
   request-target string (typically path + query) and not the method,
   scheme, or authority; those are only protected if separately covered
   (e.g., @method, @scheme, @authority).

9.2.3.  Limitations

   Unlike transport-layer authentication, application-layer
   authentication does not inherently provide channel binding to the
   underlying secure transport.  As a result, implementations MUST
   consider the risk of message relay or replay if tokens or signed
   messages are accepted outside their intended context.  Deployments
   typically mitigate these risks through short token lifetimes,
   audience restrictions, nonce or unique identifier checks, and binding
   authentication to specific requests or transaction parameters.

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10.  Agent Authorization

   Agents act on behalf of a user, a system, or on their own behalf as
   shown in Figure 1 and need to obtain authorization when interacting
   with protected resources.

10.1.  Leverage OAuth 2.0 as a Delegation Authorization Framework

   The widely deployed OAuth 2.0 Authorization Framework
   [OAUTH-FRAMEWORK] is a mechanism for delegated authorization that
   enables an Agent to obtain limited access to a protected resource
   (e.g., a service or API), intermediated by an Authorization Server,
   often with the explicit approval of the authenticated User.  An Agent
   uses OAuth 2.0-based mechanisms to obtain authorization from a User,
   a System, or on its own behalf.  OAuth 2.0 defines a wide range of
   authorization grant flows that supports these scenarios.  In these
   Oauth 2.0 flows, an Agent acts as an OAuth 2.0 Client to an OAuth 2.0
   Authorization Server, which receives the request, evaluate the
   authorization policy and returns an access token, which the Agent
   presents to the Resource Server (i.e. the protected resources such as
   the LLM or Tools in Figure 1, which can evaluate its authorization
   policy and complete the request.

10.2.  Use of OAuth 2.0 Access Tokens

   An OAuth access token represents the authorization granted to the
   Agent.  In many deployments, access tokens are structured as JSON Web
   Tokens (JWTs) [OAUTH-ACCESSTOKEN-JWT], which include claims such as
   'client_id', 'sub', 'aud', 'scope', and other attributes relevant to
   authorization.  The access token includes the Agent identity as the
   'client_id' claim as defined in Section 2.2 of
   [OAUTH-ACCESSTOKEN-JWT].

   When the Agent is acting on-behalf of another User or System, the
   User or System identifier is conveyed in the 'sub' claim as defined
   in Section 2.2 of [OAUTH-ACCESSTOKEN-JWT].  These identifiers MUST be
   used by resource servers protected by the OAuth 2.0 authorization
   service, along with other claims in the access token, to determine if
   access to a resource should be allowed.  The access token typically
   includes additional claims to convey contextual, attestation-derived,
   or policy-related information that enables fine-grained access
   control.  The resource server uses the access token and the
   information it contains along with other authorization systems (e.g.
   policy based, attribute based or role based authorization systems)
   when enforcing access control.  JWT access tokens can be validated
   directly by resource servers while other formats that are opaque to
   the resource server can be validated through a mechanism that calls
   back to the authorization server (the mechanism is called

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   introspection despite the word having nearly the opposite meaning).
   This framework supports both models and does not require a specific
   token format, provided that equivalent authorization semantics are
   maintained.

   A resource server in receipt of tokens opaque to it are able to
   obtain authorization and other information from the token through
   OAuth 2.0 Token Introspection [OAUTH-TOKEN-INTROSPECTION].  The
   introspection response provides the active state of the token and
   associated authorization attributes equivalent to those conveyed in
   structured tokens.

10.3.  Obtaining an OAuth 2.0 Access Token

   OAuth 2.0 defines a number authorization grant flows in support of
   different authorization scenarios.  The appropriate flow depends on
   the specific authorization scenario and the nature of User
   involvement.  The following subsections describe the most relevant
   flows for Agent authorization.

10.3.1.  User Delegates Authorization

   When a User grants authorization to an Agent for access to one or
   more resources (Tools, LLMs, etc.), the Authorization Code Grant, as
   described in Section 4.1 of [OAUTH-FRAMEWORK], is the canonical means
   of obtaining an access token.  This redirection-based flow involves
   an interactive authorization process in which the user authenticates
   to the authorization server and explicitly approves the requested
   access.  The resulting access token reflects the authorization
   delegated to the Agent by the User and can be used by the Agent to
   access resources on behalf of the user.

10.3.2.  Agent Obtains Own Authorization

   Agents obtaining access tokens on their own behalf can use the Client
   Credentials Grant as described in Section 4.4 of [OAUTH-FRAMEWORK] or
   the JWT Authorization Grant as described in Section 2.1 of
   [OAUTH-CLIENTAUTH-JWT].  When using the Client Credentials Grant, the
   Agent authenticates itself using one of the mechanisms described in
   Section 9 and not with the use of static, long-lived client secrets.
   When using the JWT Authorization Grant, the Agent will be identified
   in the subject of the JWT assertion.

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10.3.3.  Agents Accessed by Systems or Other Agents

   Agents themselves can act in the role of an OAuth protected resource
   and be invoked by a System (e.g. a batch job) or another Agent.  The
   System obtains an access token using an appropriate mechanism and
   then invokes the Agent presenting the access token.

10.3.4.  OAuth 2.0 Security Best Practices

   The Best Current Practice for OAuth 2.0 Security as described in
   [OAUTH-BCP] are applicable when requesting and using access tokens.

10.4.  Risk Reduction with Transaction Tokens

   Resources servers, whether they are LLMs, Tools or Agents (in the
   Agent-to-Agent case) may be composed of multiple microservices that
   are invoked to complete a request.  The access tokens presented to
   the Agent, LLM or Tools can typically be used with multiple
   transactions and consequently have broader scope than needed to
   complete any specific transaction.  Passing the access token from one
   microservice to another within an invoked Agent, LLM or the Tools
   increases the risk of token theft and replay attacks.  For example,
   an attacker may discover and access token passed between
   microservices in a log file or crash dump, exfiltrate it, and use it
   to invoke a new transaction with different parameters (e.g. increase
   the transaction amount, or invoke an unrelated call as part of
   executing a lateral move).

   To avoid passing access tokens between microservices, the Agent, LLM
   or Tools can exchange the received access token for a transaction
   token, as defined in the Transaction Token specification
   [OAUTH-TXN-TOKENS].  The transaction token allows for identity and
   authorization information to be passed along the internal call chain
   of microservices.  The transaction token issuer enriches the
   transaction token with context of the caller that presented the
   access token (e.g. IP address, etc.), transaction context
   (transaction amount), identity information and a unique transaction
   identifier.  This results in a downscoped token that is bound to a
   specific transaction and cannot be used as an access token, with
   another transaction, or within the same transaction with modified
   transaction details (e.g. change in transaction amount).  Transaction
   tokens are typically short-lived, further limiting the risk in case
   they are obtained by an attacker by limiting the time window during
   which these tokens will be accepted.

   A transaction token MAY be used to obtain an access token to call
   another service (e.g. another Agent, Tool or LLM) by using OAuth 2.0
   Token Exchange as defined in [OAUTH-TOKEN-EXCHANGE].

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10.5.  Cross Domain Access

   Agents often require access to resources that are protected by
   different OAuth 2.0 authorization servers.  When the components in
   Figure 1 are protected by different logical authorization servers, an
   Agent SHOULD use OAuth Identity and Authorization Chaining Across
   Domains as defined in ([OAUTH-ID-CHAIN]), or a derived specification
   such as the Identity Assertion JWT Authorization Grant
   [OAUTH-JWT-ASSERTION], to obtain an access token from the relevant
   authorization servers.

   When using OAuth Identity and Authorization Chaining Across Domains
   ([OAUTH-ID-CHAIN]), an Agent SHOULD use the access token or
   transaction token it received to obtain a JWT authorization grant as
   described in Section 2.3 of [OAUTH-ID-CHAIN] and then use the JWT
   authorization grant it receives to obtain an access token for the
   resource it is trying to access as defined in Section 2.4 of
   [OAUTH-ID-CHAIN].

   When using the Identity Assertion JWT Authorization Grant
   [OAUTH-JWT-ASSERTION], the identity assertion (e.g. the OpenID
   Connect ID Token or SAML assertion) for the target end-user is used
   to obtain a JWT assertion as described in Section 4.3 of
   [OAUTH-JWT-ASSERTION], which is then used to obtain an access token
   as described in Section 4.4 of [OAUTH-JWT-ASSERTION].

   OAuth Identity and Authorization Chaining Across Domains
   ([OAUTH-ID-CHAIN]) provides a general mechanism for obtaining cross-
   domain access that can be used whether an identity assertion like a
   SAML or OpenID Connect token is available or not.  The Identity
   Assertion JWT Authorization Grant [OAUTH-JWT-ASSERTION] is optimized
   for cases where an identity assertion like a SAML or OpenID Connect
   token is available from an identity provider that is trusted by all
   the OAuth authorization servers as it removes the need for the user
   to re-authenticate.  This is typically used within enterprise
   deployments to simplify authorization delegation for multiple
   software-as-a-service offerings.

10.6.  Human in the Loop

   An OAuth authorization server MAY conclude that the level of access
   requested by an Agent requires explicit user confirmation.  In such
   cases the authorization server SHOULD either decline the request or
   obtain additional authorization from the User.  An Agent, acting as
   an OAuth client, may use the OpenID Client Initiated Backchannel
   Authentication (CIBA) protocol.  This triggers an out-of-band
   interaction allowing the user to approve or deny the requested
   operation without exposing credentials to the agent (for example a

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   push notification requesting the user to approve a request through an
   authenticator application on their mobile device).

   Interactive agent frameworks may also solicit user confirmation
   directly during task execution (for example tool invocation approval
   or parameter confirmation).  Such interactions do not by themselves
   constitute authorization and MUST be bound to a verifiable
   authorization grant issued by the authorization server.  The agent
   SHOULD therefore translate user confirmation into an OAuth
   authorization event (e.g., step-up authorization via CIBA) before
   accessing protected resources.

   This model aligns with user-solicitation patterns such as those
   described by the Model Context Protocol ([MCP]), where an agent
   pauses execution and requests user confirmation before performing
   sensitive actions.  The final authorization decision remains with the
   authorization server, and the agent MUST NOT treat local UI
   confirmation alone as sufficient authorization.

   *Note:* Additional specification or design work may be needed to
   define how out-of-band interactions with the User occur at different
   stages of execution.  CIBA itself only accounts for client
   initiation, which doesn't map well to cases that envision the need
   for User confirmation to occur mid-execution.

10.7.  Tool-to-Service Access

   Tools expose interfaces to underlying services and resources.  Access
   to the Tools can be controlled by OAuth and augmented by policy,
   attribute or role based authorization systems (amongst others).  If
   the Tools are implemented as one or more microservices, it should use
   transaction tokens to reduce risk as described in Section 10.4 to
   avoid passing access tokens around within the Tool implementation.

   Access from the Tools to the resources and services MAY be controlled
   through a variety of authorization mechanisms, including OAuth.  If
   access is controlled through OAuth, the Tools can use OAuth 2.0 Token
   Exchange as defined in [OAUTH-TOKEN-EXCHANGE] to exchange the access
   token it received for a new access token to access the resource or
   service in question.  When the Tool needs access to a resource
   protected by an authorization server other than the Tool's own
   authorization server, the OAuth Identity and Authorization Chaining
   Across Domains ([OAUTH-ID-CHAIN]) can be used to obtain an access
   token from the authorization server protecting that resource.

   *Note:* It is an anti-pattern for Tools to forward access tokens it
   received from the Agent to Services or Resources.  It increases the
   risk of credential theft and lateral attacks.

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10.8.  Privacy Considerations {privacy-considerations}

   Authorization tokens may contain user identifiers, agent identifiers,
   audience restrictions, transaction details, and contextual
   attributes.  Deployments SHOULD minimize disclosure of personally
   identifiable or sensitive information in tokens and prefer audience-
   restricted and short-lived tokens.  Where possible, opaque tokens
   with introspection SHOULD be preferred when claim minimization is
   required.

   Agents SHOULD request only the minimum scopes and authorization
   details necessary to complete a task.  Resource servers SHOULD avoid
   logging full tokens and instead log token identifiers or hashes.
   When authorization context is propagated across services, derived or
   down-scoped tokens (such as transaction tokens) SHOULD be used to
   reduce correlation and replay risk.

   Implementations MUST ensure that user identity information delegated
   to agents is not exposed to unrelated services and that cross-domain
   authorization exchanges only disclose information required for the
   target authorization decision.

10.9.  OAuth 2.0 Discovery in Dynamic Environments

   In dynamic Agent deployments (e.g., ephemeral workloads, multi-tenant
   services, and frequently changing endpoint topology), Agents and
   other participants MAY use OAuth discovery mechanisms to reduce
   static configuration and to bind runtime decisions to verifiable
   metadata.

10.9.1.  Authorization Server Capability Discovery

   An Agent that needs to obtain tokens can discover authorization
   server endpoints and capabilities using OAuth 2.0 Authorization
   Server Metadata [OAUTH-SERVER-METADATA] and/or OpenID Connect
   Discovery [OpenIDConnect.Discovery].  This allows the Agent to learn
   the authorization server issuer identifier, authorization and token
   endpoints, supported grant types, client authentication methods,
   signing keys (via jwks_uri), and other relevant capabilities without
   preconfiguring them.

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10.9.2.  Protected Resource Capability Discovery

   When an Agent is invoking a Tool, the Agent MAY use OAuth 2.0
   Protected Resource Metadata [OAUTH-RESOURCE-METADATA] to discover how
   the resource is protected, including the resource identifier and the
   applicable Authorization Server(s) that protects Tool access.  This
   enables an Agent to select the correct issuer/audience and token
   acquisition flow at runtime, even when resources are deployed or
   moved dynamically.

   A Tool that attempts to access and OAuth protected resource MAY use
   OAuth 2.0 Protected Resource Metadata [OAUTH-RESOURCE-METADATA] in a
   similar way as an Agent.  Similarly, a System may use
   [OAUTH-RESOURCE-METADATA] when accessing an Agent.

10.9.3.  Client Capability Discovery

   Other actors (e.g., Authorization Servers, registrars, or policy
   systems) may need to learn about any entities (System, Agent, Tool)
   that acts as OAuth clients.  Where supported, they MAY use Client ID
   Metadata Documents [OAUTH-CLIENT-METADATA], which allow a client to
   host its metadata at a URL-valued client_id so that the relying party
   can retrieve client properties (e.g., redirect URIs, display
   information, and other registered client metadata) without prior
   bilateral registration.

   As an alternative, entities acting as OAuth clients MAY register
   their capabilities with authorization servers as defined in the OAuth
   2.0 Dynamic Client Registration Protocol [OAUTH-REGISTRATION].

11.  Agent Monitoring, Observability and Remediation

   Because agents may perform sensitive actions autonomously or on
   behalf of users, deployments MUST maintain sufficient monitoring and
   observability to reconstruct agent behavior and authorization context
   after execution.  Observability is therefore a security control, not
   solely an operational feature.

   Any participant in the system, including the Agent, Tool, System, LLM
   or other resources and service MAY subscribe to change notifications
   using eventing mechanisms such as the OpenID Shared Signals Framework
   [SSF] with either the Continuous Access Evaluation Profile [CAEP] or
   Risk Incident Sharing and Coordination [RISC] to receive security and
   authorization-relevant signals.  Upon receipt of a relevant signal
   (e.g., session revoked, risk level change, subject disabled, token
   replay suspected, risk elevated), the recipient SHOULD remediate by
   attenuating access, such as terminating local sessions, discarding
   cached tokens, re-acquiring tokens with updated constraints, reducing

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   privileges, or re-running policy evaluation before continuing to
   allow access.  Recipients of such signals MUST ensure that revoked or
   downgraded authorization is enforced without undue delay.  Cached
   authorization decisions and tokens that are no longer valid MUST NOT
   continue to be used after a revocation or risk notification is
   received.

   To support detection, investigation, and accountability, deployments
   MUST produce durable audit logs covering authorization decisions and
   subsequent remediations.  Audit records MUST be tamper-evident and
   retained according to the security policy of the deployment.

   At a minimum, audit events MUST record:

   *  authenticated agent identifier

   *  delegated subject (user or system), when present

   *  resource or tool being accessed

   *  action requested and authorization decision

   *  timestamp and transaction or request correlation identifier

   *  attestation or risk state influencing the decision

   *  remediation or revocation events and their cause

   Monitoring / Observability systems SHOULD correlate events across
   Agents, Tools, Services, Resources and LLMs to detect misuse patterns
   such as replay, confused deputy behavior, privilege escalation, or
   unexpected action sequences.

   End-to-end audit is enabled when Agents, Users, Systems, LLMs, Tools,
   services and resources have stable, verifiable identifiers that allow
   auditors to trace "which entity did what, using which authorization
   context, and why access changed over time."

   Implementations SHOULD provide operators the ability to reconstruct a
   complete execution chain of an agent task, including delegated
   authority, intermediate calls, and resulting actions across service
   boundaries.

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12.  Agent Authentication and Authorization Policy

   The configuration and runtime parameters for Agent Identifiers
   Section 5, Agent Credentials Section 6, Agent Attestation Section 7,
   Agent Credential Provisioning Section 8, Agent Authentication
   Section 9, Agent Authorization Section 10 and Agent Monitoring,
   Observability and Remediation Section 11 collectively constitute the
   authentication and authorization policy within which the Agent
   operates.

   Because these parameters are highly deployment and risk-model-
   specific (and often reflect local governance, regulatory, and
   operational constraints), the policy model and document format are
   out of scope for this framework and are not recommended as a target
   for standardization within this specification.  Implementations MAY
   represent policy in any suitable “policy-as-code” or configuration
   format (e.g., JSON/YAML), provided it is versioned, reviewable, and
   supports consistent evaluation across the components participating in
   the end-to-end flow.

13.  Agent Compliance

   Compliance for Agent-based systems SHOULD be assessed by auditing
   observed behavior and recorded evidence (logs, signals, and
   authorization decisions) against the deployment’s Agent
   Authentication and Authorization Policy Section 12.  Since compliance
   criteria are specific to individual deployments, organizations,
   industries and jurisdictions, they are out of scope for this
   framework though implementers SHOULD ensure strong observability and
   accountable governance, subject to their specific business needs.

14.  Security Considerations

   TODO Security

15.  Privacy Considerations

   TODO Privacy but there's also Section 15...

16.  IANA Considerations

   This document has no IANA actions.

17.  Acknowledgments

   The authors would like to thank Sean O'Dell for providing valuable
   input and feedback on this work.

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18.  Normative References

   [A2A]      "Agent2Agent (A2A) Protocol", n.d.,
              <https://github.com/a2aproject/A2A>.

   [ACP]      "Agentic Commerce Protocol", n.d.,
              <https://www.agenticcommerce.dev/docs>.

   [AP2]      "Agent Payments Protocol (AP2)", n.d.,
              <https://github.com/google-agentic-commerce/AP2>.

   [CAEP]     "OpenID Continuous Access Evaluation Profile 1.0", n.d.,
              <https://openid.net/specs/openid-caep-1_0-final.html>.

   [HTTP-SIG] Backman, A., Ed., Richer, J., Ed., and M. Sporny, "HTTP
              Message Signatures", RFC 9421, DOI 10.17487/RFC9421,
              February 2024, <https://www.rfc-editor.org/rfc/rfc9421>.

   [MCP]      "Model Context Protocol", n.d.,
              <https://modelcontextprotocol.io/specification>.

   [OAUTH-ACCESSTOKEN-JWT]
              Bertocci, V., "JSON Web Token (JWT) Profile for OAuth 2.0
              Access Tokens", RFC 9068, DOI 10.17487/RFC9068, October
              2021, <https://www.rfc-editor.org/rfc/rfc9068>.

   [OAUTH-BCP]
              Lodderstedt, T., Bradley, J., Labunets, A., and D. Fett,
              "Best Current Practice for OAuth 2.0 Security", BCP 240,
              RFC 9700, DOI 10.17487/RFC9700, January 2025,
              <https://www.rfc-editor.org/rfc/rfc9700>.

   [OAUTH-CLIENT-METADATA]
              Parecki, A. and E. Smith, "OAuth Client ID Metadata
              Document", Work in Progress, Internet-Draft, draft-ietf-
              oauth-client-id-metadata-document-01, 1 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-oauth-
              client-id-metadata-document-01>.

   [OAUTH-CLIENTAUTH-JWT]
              Jones, M., Campbell, B., and C. Mortimore, "JSON Web Token
              (JWT) Profile for OAuth 2.0 Client Authentication and
              Authorization Grants", RFC 7523, DOI 10.17487/RFC7523, May
              2015, <https://www.rfc-editor.org/rfc/rfc7523>.

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   [OAUTH-FRAMEWORK]
              Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
              RFC 6749, DOI 10.17487/RFC6749, October 2012,
              <https://www.rfc-editor.org/rfc/rfc6749>.

   [OAUTH-ID-CHAIN]
              Schwenkschuster, A., Kasselman, P., Burgin, K., Jenkins,
              M. J., and B. Campbell, "OAuth Identity and Authorization
              Chaining Across Domains", Work in Progress, Internet-
              Draft, draft-ietf-oauth-identity-chaining-08, 9 February
              2026, <https://datatracker.ietf.org/doc/html/draft-ietf-
              oauth-identity-chaining-08>.

   [OAUTH-JWT-ASSERTION]
              Parecki, A., McGuinness, K., and B. Campbell, "Identity
              Assertion JWT Authorization Grant", Work in Progress,
              Internet-Draft, draft-ietf-oauth-identity-assertion-authz-
              grant-02, 2 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-oauth-
              identity-assertion-authz-grant-02>.

   [OAUTH-REGISTRATION]
              Richer, J., Ed., Jones, M., Bradley, J., Machulak, M., and
              P. Hunt, "OAuth 2.0 Dynamic Client Registration Protocol",
              RFC 7591, DOI 10.17487/RFC7591, July 2015,
              <https://www.rfc-editor.org/rfc/rfc7591>.

   [OAUTH-RESOURCE-METADATA]
              Jones, M.B., Hunt, P., and A. Parecki, "OAuth 2.0
              Protected Resource Metadata", RFC 9728,
              DOI 10.17487/RFC9728, April 2025,
              <https://www.rfc-editor.org/rfc/rfc9728>.

   [OAUTH-SERVER-METADATA]
              Jones, M., Sakimura, N., and J. Bradley, "OAuth 2.0
              Authorization Server Metadata", RFC 8414,
              DOI 10.17487/RFC8414, June 2018,
              <https://www.rfc-editor.org/rfc/rfc8414>.

   [OAUTH-TOKEN-EXCHANGE]
              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>.

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   [OAUTH-TOKEN-INTROSPECTION]
              Richer, J., Ed., "OAuth 2.0 Token Introspection",
              RFC 7662, DOI 10.17487/RFC7662, October 2015,
              <https://www.rfc-editor.org/rfc/rfc7662>.

   [OAUTH-TXN-TOKENS]
              Tulshibagwale, A., Fletcher, G., and P. Kasselman,
              "Transaction Tokens", Work in Progress, Internet-Draft,
              draft-ietf-oauth-transaction-tokens-08, 2 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-oauth-
              transaction-tokens-08>.

   [OpenIDConnect.AuthZEN]
              Gazitt, O., Ed., Brossard, D., Ed., and A. Tulshibagwale,
              Ed., "Authorization API 1.0", 2026,
              <https://openid.net/specs/authorization-api-1_0.html>.

   [OpenIDConnect.CIBA]
              "OpenID Connect Client-Initiated Backchannel
              Authentication Flow - Core 1.0", n.d.,
              <https://openid.net/specs/openid-client-initiated-
              backchannel-authentication-core-1_0.html>.

   [OpenIDConnect.Discovery]
              "OpenID Connect Discovery 1.0", n.d.,
              <https://openid.net/specs/openid-connect-discovery-
              1_0-final.html>.

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

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

   [RISC]     "OpenID Risk Incident Sharing and Coordination Profile
              1.0", n.d.,
              <https://openid.net/specs/openid-risc-1_0-final.html>.

   [SPIFFE]   "Secure Production Identity Framework for Everyone", n.d.,
              <https://spiffe.io/docs/latest/spiffe-about/overview/>.

   [SPIFFE-ID]
              "SPIFFE-ID", n.d.,
              <https://github.com/spiffe/spiffe/blob/main/standards/
              SPIFFE-ID.md>.

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   [SSF]      "OpenID Shared Signals Framework Specification 1.0", n.d.,
              <https://openid.net/specs/openid-sharedsignals-framework-
              1_0-final.html>.

   [WIMSE-ARCH]
              Salowey, J. A., Rosomakho, Y., and H. Tschofenig,
              "Workload Identity in a Multi System Environment (WIMSE)
              Architecture", Work in Progress, Internet-Draft, draft-
              ietf-wimse-arch-07, 2 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-wimse-
              arch-07>.

   [WIMSE-CRED]
              Campbell, B., Salowey, J. A., Schwenkschuster, A.,
              Sheffer, Y., and Y. Rosomakho, "WIMSE Workload
              Credentials", Work in Progress, Internet-Draft, draft-
              ietf-wimse-workload-creds-00, 3 November 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-wimse-
              workload-creds-00>.

   [WIMSE-HTTPSIG]
              Salowey, J. A. and Y. Sheffer, "WIMSE Workload-to-Workload
              Authentication with HTTP Signatures", Work in Progress,
              Internet-Draft, draft-ietf-wimse-http-signature-02, 1
              March 2026, <https://datatracker.ietf.org/doc/html/draft-
              ietf-wimse-http-signature-02>.

   [WIMSE-ID] Rosomakho, Y. and J. A. Salowey, "Workload Identifier",
              Work in Progress, Internet-Draft, draft-ietf-wimse-
              identifier-02, 2 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-wimse-
              identifier-02>.

   [WIMSE-WPT]
              Campbell, B. and A. Schwenkschuster, "WIMSE Workload Proof
              Token", Work in Progress, Internet-Draft, draft-ietf-
              wimse-wpt-01, 2 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-wimse-
              wpt-01>.

Appendix A.  Document History

   [[ To be removed from the final specification ]]

   *  latest

   *  Add Nick Steele from OpenAI as co-author.

Kasselman, et al.        Expires 1 October 2026                [Page 25]
Internet-Draft                   AI-Auth                      March 2026

   -00

Authors' Addresses

   Pieter Kasselman
   Defakto Security
   Email: pieter@defakto.security

   Jean-François Lombardo
   AWS
   Email: jeffsec@amazon.com

   Yaroslav Rosomakho
   Zscaler
   Email: yrosomakho@zscaler.com

   Brian Campbell
   Ping Identity
   Email: bcampbell@pingidentity.com

   Nick Steele
   Open AI
   Email: steele@openai.com

Kasselman, et al.        Expires 1 October 2026                [Page 26]