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<reference anchor="I-D.hood-independent-agtp" target="https://datatracker.ietf.org/doc/html/draft-hood-independent-agtp-08">
   <front>
      <title>Agent Transfer Protocol (AGTP)</title>
      <author initials="C." surname="Hood" fullname="Chris Hood">
         <organization>Nomotic, Inc.</organization>
      </author>
      <date month="May" day="25" year="2026" />
      <abstract>
	 <t>   AI agents and agentic systems generate a growing volume of intent-
   driven, unstructured, and undifferentiated traffic that flows through
   HTTP indistinguishably from human-initiated requests.  HTTP lacks the
   semantic vocabulary, observability primitives, and identity
   mechanisms required by agent systems operating at scale.  Existing
   protocols described as Agent Group Messaging Protocols (AGMP),
   including MCP, ACP, A2A, and ANP, are messaging-layer constructs that
   presuppose HTTP as their transport.  They do not address the
   underlying transport problem.

   This document defines the Agent Transfer Protocol (AGTP): a dedicated
   application-layer protocol for AI agent traffic.  AGTP is a runtime
   contract negotiation substrate (RCNS): a transport that fixes only a
   eighteen-method protocol floor and negotiates any additional method
   surface at runtime between agent and server in a single round-trip,
   governed by the AGTP-API companion specification [AGTP-API], which
   defines the curated method catalog, path grammar, endpoint primitive,
   and synthesis semantics.  Version 07 confirms the IANA-registered
   agtp:// URI scheme and IANA-assigned port 4480 for TCP/TLS and QUIC,
   formalizes Form 1a URI grammar (agtp://{agent-id}@{host}) for direct
   addressing, renames the Agent Manifest Document to the Agent Identity
   Document with an enumerated schema, redesigns the protocol-defined
   method floor to a 12-method set organized as six cognitive verbs
   (QUERY, DISCOVER, DESCRIBE, SUMMARIZE, PLAN, PROPOSE) and six
   mechanics verbs (EXECUTE, DELEGATE, ESCALATE, CONFIRM, SUSPEND,
   NOTIFY), establishes AGTP as a substrate for higher-level agent
   frameworks (MCP, A2A, ACP) carried as content types inside AGTP
   method invocations, renumbers AGTP-specific status codes out of HTTP-
   assigned space to avoid semantic collision, mandates explicit
   Content-Length framing with a prohibition on TLS socket-level half-
   close, adds a .well-known/agtp bootstrap convention per RFC 8615,
   deprecates the AGIS reference and the proposed AGTP-Methods
   specification by folding both into the unified AGTP-API contract
   layer, adds status codes 405 (Method Not Allowed), 459 (Method
   Violation), and 460 (Endpoint Violation) per the AGTP-API contract
   model, and adopts &quot;Agent Genesis&quot; as the canonical term for the
   permanent signed origin document.  Version 06 prepared the IANA
   Service Name and Port Number application and consolidated the URI
   scheme registration.  Version 05 restored the canonical Agent-ID as
   the primary identity primitive and decoupled Trust Tier 1
   verification from DNS as a sole requirement.  A canonical Agent-ID is
   derived from the agent&#x27;s Agent Genesis hash and is authoritative in
   every AGTP protocol operation.  Three equivalent verification paths
   are recognized for Trust Tier 1: DNS-anchored verification via RFC
   8555 ACME challenge, log-anchored verification via Agent Genesis
   inclusion in an append-only transparency log aligned with RFC 9162
   and RFC 9943 (SCITT), and hybrid verification combining DNS control
   with blockchain address ownership.  Version 04 introduced normative
   integration hooks for the AGTP Merchant Identity and Agentic Commerce
   Binding specification [AGTP-MERCHANT], which defines the merchant-
   side identity model that complements AGTP&#x27;s agent-side identity
   model.  AGTP SHOULD prefer QUIC for new implementations and MUST
   support TCP/TLS for compatibility and fallback.  It is designed to be
   composable with existing agent frameworks, not to replace them.

	 </t>
      </abstract>
   </front>
   <seriesInfo name="Internet-Draft" value="draft-hood-independent-agtp-08" />
   
</reference>
