--- type: Agentic Web Standard title: "Agent Discovery Protocol (ADP) v1.1" description: "How does an agent escalate from a cheap DNS lookup, to a well-known JSON metadata document, to a real-time WebSocket session, using only as much machinery as the task needs?" resource: "https://www.ietf.org/archive/id/draft-pro-adp-agent-discovery-02.txt" tags: ["discover", "well-known-file", "ietf", "discover-my-api", "describe-agent-capabilities", "agent-to-agent-messaging", "agent-naming"] status: draft generated: { by: agenticweb-builder/1.0, at: 2026-10-30T00:00:00Z } verified: { by: process:agenticweb-engine, at: 2026-10-29T00:00:00Z } stale_after: 2026-11-28T00:00:00Z sources: - id: ref-1 resource: "https://www.ietf.org/archive/id/draft-pro-adp-agent-discovery-02.txt" title: "Internet-Draft text, draft-pro-adp-agent-discovery-02, checked 2026-10-29: \"Agent Discovery Protocol (ADP) v1.1 — Well-Known Metadata and Interaction Layer\" \"draft-pro-adp-agent-discovery-02\" \"Network Working Group Bin. Lian Internet-Draft aipair.ai\" \"Intended status: Informational\" \"18 June 2026\" \"Expires: 20 December 2026\" \"This Internet-Draft will expire on 20 December 2026.\" \"This document defines the Agent Discovery Protocol (ADP) v1.1, a layered protocol for discovering, verifying, and interacting with AI Agents on the Internet.\" \"ADP delegates DNS discovery to DNS-AID (SVCB records) and defines a Well-Known JSON metadata format, an Ed25519-based identity model, and the Agent Gateway Protocol (AGP) for real-time WebSocket messaging.\" \"ADP v1.1 adopts DNS-AID as its normative DNS discovery mechanism.\" \"The original TXT+SRV scheme is retained as a documented fallback\" \"No central registry; domain ownership is the root of identity.\"" last_modified: 2026-06-18T00:00:00Z - id: ref-2 resource: "https://datatracker.ietf.org/doc/draft-pro-adp-agent-discovery/" title: "IETF Datatracker, document page for draft-pro-adp-agent-discovery, checked 2026-10-29: \"Author Bin Lian\" \"Active Internet-Draft (individual)\" \"IESG state I-D Exists\" \"This I-D is not endorsed by the IETF and has no formal standing in the IETF standards process.\" \"RFC stream (None)\" \"Last updated 2026-07-24\" \"Last updated 2026-07-24 (Latest revision 2026-06-23)\"" last_modified: 2026-07-24T00:00:00Z - id: ref-3 resource: "https://datatracker.ietf.org/api/v1/doc/document/draft-pro-adp-agent-discovery/" title: "IETF Datatracker API, document record for draft-pro-adp-agent-discovery (UTC), checked 2026-10-29: \"\"rev\": \"02\"\" \"\"expires\": \"2026-12-25T20:14:58Z\"\" \"\"pages\": 27\"" last_modified: 2026-10-29T00:00:00Z - id: ref-4 resource: "https://datatracker.ietf.org/api/v1/doc/newrevisiondocevent/?doc__name=draft-pro-adp-agent-discovery&format=json" title: "IETF Datatracker API, revision events for draft-pro-adp-agent-discovery (UTC), checked 2026-10-29: \"\"rev\": \"00\", \"time\": \"2026-06-09T14:01:06Z\"\" \"\"total_count\": 3\" \"\"rev\": \"02\", \"time\": \"2026-06-23T20:14:58Z\"\"" last_modified: 2026-10-29T00:00:00Z --- # Agent Discovery Protocol (ADP) v1.1 Agent Discovery Protocol (ADP) v1.1 is an agentic-web standard (well-known file — /.well-known/agent.json) at step 1, Discover, governed by Individual IETF submission; its status is "Active Internet-Draft". It answers: "How does an agent escalate from a cheap DNS lookup, to a well-known JSON metadata document, to a real-time WebSocket session, using only as much machinery as the task needs?" Implementation status is prototype, last verified 2026-10-29. # Overview ADP is a discovery protocol for AI agents: "This document defines the Agent Discovery Protocol (ADP) v1.1, a layered protocol for discovering, verifying, and interacting with AI Agents on the Internet." [^ref-1]. It reuses other work for DNS and adds its own layers: "ADP delegates DNS discovery to DNS-AID (SVCB records) and defines a Well-Known JSON metadata format, an Ed25519-based identity model, and the Agent Gateway Protocol (AGP) for real-time WebSocket messaging." [^ref-1]. Version 1.1 hands the DNS layer to DNS-AID: "ADP v1.1 adopts DNS-AID as its normative DNS discovery mechanism." [^ref-1]. The older DNS method stays as a backup: "The original TXT+SRV scheme is retained as a documented fallback" [^ref-1]. It has no central registry: "No central registry; domain ownership is the root of identity." [^ref-1]. *This short entry has no "Who uses it" or "Who reads it" sections. It makes no claims about adoption or usage; none were checked.* # Examples ```http GET https://{origin}/.well-known/agent.json # parse: 200 response is a JSON document with identity/endpoints/capabilities/security top-level blocks # on absent: Domain does not publish ADP Layer 2 metadata; check for a DNS-AID SVCB record with a well-known SvcParamKey as a possible Layer 1-only deployment ``` # Knowledge Graph * **Lifecycle Step**: [1 Discover](/category/discover/index.md) * **Builds on**: [DNS-AID (DNS for AI Discovery)](/okf/protocols/dns-aid.md) * **Pairs with**: [DNS-AID (DNS for AI Discovery)](/okf/protocols/dns-aid.md), [Agent Identity & Discovery (AID)](/okf/protocols/aid.md), [Agentic Resource Discovery (ARD)](/okf/protocols/ard.md) * **Compared in**: [Agent Identity & Discovery (AID) vs Agent Discovery Protocol (ADP) v1.1](/compare/aid-vs-adp/index.md) [^ref-1]: Internet-Draft text, draft-pro-adp-agent-discovery-02, checked 2026-10-29: "Agent Discovery Protocol (ADP) v1.1 — Well-Known Metadata and Interaction Layer" "draft-pro-adp-agent-discovery-02" "Network Working Group Bin. Lian Internet-Draft aipair.ai" "Intended status: Informational" "18 June 2026" "Expires: 20 December 2026" "This Internet-Draft will expire on 20 December 2026." "This document defines the Agent Discovery Protocol (ADP) v1.1, a layered protocol for discovering, verifying, and interacting with AI Agents on the Internet." "ADP delegates DNS discovery to DNS-AID (SVCB records) and defines a Well-Known JSON metadata format, an Ed25519-based identity model, and the Agent Gateway Protocol (AGP) for real-time WebSocket messaging." "ADP v1.1 adopts DNS-AID as its normative DNS discovery mechanism." "The original TXT+SRV scheme is retained as a documented fallback" "No central registry; domain ownership is the root of identity." (https://www.ietf.org/archive/id/draft-pro-adp-agent-discovery-02.txt) [^ref-2]: IETF Datatracker, document page for draft-pro-adp-agent-discovery, checked 2026-10-29: "Author Bin Lian" "Active Internet-Draft (individual)" "IESG state I-D Exists" "This I-D is not endorsed by the IETF and has no formal standing in the IETF standards process." "RFC stream (None)" "Last updated 2026-07-24" "Last updated 2026-07-24 (Latest revision 2026-06-23)" (https://datatracker.ietf.org/doc/draft-pro-adp-agent-discovery/) [^ref-3]: IETF Datatracker API, document record for draft-pro-adp-agent-discovery (UTC), checked 2026-10-29: ""rev": "02"" ""expires": "2026-12-25T20:14:58Z"" ""pages": 27" (https://datatracker.ietf.org/api/v1/doc/document/draft-pro-adp-agent-discovery/) [^ref-4]: IETF Datatracker API, revision events for draft-pro-adp-agent-discovery (UTC), checked 2026-10-29: ""rev": "00", "time": "2026-06-09T14:01:06Z"" ""total_count": 3" ""rev": "02", "time": "2026-06-23T20:14:58Z"" (https://datatracker.ietf.org/api/v1/doc/newrevisiondocevent/?doc__name=draft-pro-adp-agent-discovery&format=json)