{
 "acronym": "ADP",
 "adoption": {
  "by": null,
  "level": "unmeasured",
  "probe_run": null
 },
 "aliases": [],
 "analog": "a layered service-discovery stack (DNS SRV -> REST descriptor -> live connection), akin to how email escalates from MX lookup to SMTP handshake",
 "collisions": [
  "ADP is a generic acronym also used for 'Agile Development Process' and unrelated ADP payroll/HR company; within the agentic space, distinct from ARDP (Agent Registration and Discovery Protocol) and AID/DNS-AID"
 ],
 "discovery": {
  "mechanism": "Layer 1 DNS-AID (SVCB/TLSA), Layer 2 well-known JSON metadata, Layer 3 HTML landing page + JSON-LD + WebSocket (Agent Gateway Protocol)",
  "path": "/.well-known/agent.json"
 },
 "dispute": null,
 "evidence": [
  {
   "claim": "draft-pro-adp-agent-discovery-02 (18 June 2026) defines ADP v1.1 as a three-layer stack: Layer 1 delegates entirely to DNS-AID (SVCB records), Layer 2 defines a GET-able /.well-known/agent.json metadata document, and Layer 3 defines an HTML landing page plus a WebSocket-based Agent Gateway Protocol (AGP) with Ed25519 signature authentication for real-time messaging.",
   "date": "2026-06-18",
   "label": "VERIFIED",
   "url": "https://datatracker.ietf.org/doc/html/draft-pro-adp-agent-discovery-02"
  },
  {
   "claim": "A reference implementation exists at github.com/harrylian8766/adp-protocol (5 stars, 1 fork, fetched 2026-09-06): a Node.js SDK (protocol identifier urn:adp:1.1) implementing SVCB-first DNS discovery, TLSA/DANE, the /.well-known/agent.json builder, HTML landing-page generation, and a CLI, explicitly version-aligned with draft-pro-adp-agent-discovery-02 and cross-referencing draft-mozleywilliams-dnsop-dnsaid for SvcParamKey usage.",
   "date": "2026-09-06",
   "label": "VERIFIED",
   "url": "https://github.com/harrylian8766/adp-protocol"
  }
 ],
 "form": "well-known-file",
 "governance": "IETF individual Internet-Draft; explicitly delegates its DNS layer to the separate dnsop-area DNS-AID draft rather than defining its own",
 "group": null,
 "history": [
  {
   "date": "2026-09-05",
   "note": "seeded from Exa Agent research run"
  },
  {
   "date": "2026-09-06",
   "note": "verified against draft-pro-adp-agent-discovery-02 spec text via datatracker.ietf.org"
  },
  {
   "date": "2026-09-06",
   "note": "fix round 1: added second evidence entry (harrylian8766/adp-protocol reference implementation, fetched directly); upgraded implementation unknown -> prototype on that basis"
  }
 ],
 "id": "adp",
 "implementation": "prototype",
 "last_verified": "2026-09-06",
 "name": "Agent Discovery Protocol",
 "native_status": "Internet-Draft; work in progress",
 "origin": {
  "date": "2026-06-18",
  "org": "Individual IETF submission"
 },
 "part_of": null,
 "parties": [
  "agent-site",
  "agent-agent"
 ],
 "phase": "draft",
 "probe": {
  "method": "GET",
  "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",
  "parse": "200 response is a JSON document with identity/endpoints/capabilities/security top-level blocks",
  "path": "https://{origin}/.well-known/agent.json"
 },
 "question": "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?",
 "scope": "general",
 "spec_url": "https://datatracker.ietf.org/doc/html/draft-pro-adp-agent-discovery-02",
 "step": "discover",
 "summary_md": "The Agent Discovery Protocol (ADP) is a layered protocol, currently at v1.1, for discovering, verifying, and interacting with AI agents on the internet [1]. It is an individual IETF Internet-Draft (not adopted by any working group), revision -02, dated 18 June 2026 [1].\n\nADP's organizing idea is escalation: \"if SVCB answers your question, do not issue an HTTP request; if Well-Known suffices, do not open a WebSocket\" [1]. It is explicitly a three-layer stack. Layer 1 is DNS discovery, and rather than redefine it, ADP delegates entirely to the separate DNS-AID Internet-Draft (see `dns-aid`), reusing its SVCB records, its `well-known`/`cap`/`cap-sha256` SvcParamKeys, and its DANE TLSA-based endpoint authentication [1]. Layer 2 is a well-known JSON metadata document, published by default at `/.well-known/agent.json`, containing identity, capability, relationship, security-policy and endpoint-map blocks [1]. Layer 3 covers interaction endpoints: an HTML landing page at the domain root with embedded JSON-LD structured data for human-facing discovery, plus a WebSocket transport -- the Agent Gateway Protocol (AGP) -- for real-time inter-agent messaging authenticated with Ed25519 signatures [1]. A TXT+SRV fallback exists for organizations that cannot deploy SVCB records [1].\n\nADP does not itself mint a new DNS mechanism (Layer 1 is DNS-AID verbatim) and does not define the internal schema of whatever protocol Layer 3 ultimately hands off to (MCP, A2A, etc. remain external, similar to ARD's artifact-agnostic envelope) [1]. Because it explicitly reuses DNS-AID, the two drafts should be read together rather than as fully independent proposals: ADP's Layer 1 section is a summary that points back to the normative DNS-AID text.\n\nCurrent state: revision -02 was published 18 June 2026, expiring 20 December 2026 unless refreshed, and its \"Changes from -00\" section (part of the table of contents) indicates it is still actively being revised rather than stable [1]. A single-author reference implementation was located at github.com/harrylian8766/adp-protocol (5 stars, 1 fork, fetched 2026-09-06): a Node.js SDK and CLI implementing all three layers (SVCB-first DNS discovery aligned with DNS-AID's SvcParamKeys, the agent.json builder, HTML landing-page generation, and Ed25519 verification), published under a CC0 protocol license / MIT SDK license [2]. This is a solo hobbyist project rather than a vendor or standards-body implementation, so implementation is recorded as prototype rather than shipping; no independent deployment or adopter evidence was located, so adoption remains unmeasured.\n\nWhat is disputed or unknown: whether ADP's Layer 2/3 additions (the well-known JSON schema, the WebSocket AGP transport) will be adopted independently of whether DNS-AID itself is adopted, since the two are only loosely coupled (an implementer could deploy DNS-AID without ADP's higher layers, or vice versa using the TXT+SRV fallback); and how ADP's `/.well-known/agent.json` relates to the similarly-named but structurally different `/.well-known/agent` fallback defined by the unrelated AID specification (see `aid`) -- both use the word \"agent\" in a well-known path but are not the same document format.",
 "track": "ietf",
 "version": {
  "date": "2026-06-18",
  "label": "draft-pro-adp-agent-discovery-02"
 }
}