generated: '2026-09-19'
method: probed
source: https://mcp.horizonshield.dev/.well-known/agent-card.json
card:
  file: a2a/horizonshield-dev-agent-card.json
discovery:
  path: /.well-known/agent-card.json
  canonical: true
  host: mcp.horizonshield.dev
  note: >-
    Served from the provider's MCP host, which is also the A2A JSON-RPC endpoint the card names (url and both
    supportedInterfaces[] entries point at https://mcp.horizonshield.dev). The registrable apex horizonshield.dev
    has NO A/AAAA record on 1.1.1.1, 8.8.8.8 or 9.9.9.9 (NOERROR, ANSWER 0) and carries only identity TXT records
    ("a2a-registry-verify=a2a_2d0b…" and "v=MCPv1; k=ed25519; p=…", the a2aregistry.org and MCP-registry domain
    verifications), so there is no apex to probe — every horizonshield.dev surface lives on a subdomain. The same
    card, byte-identical except for the signatures[] block, is served at
    https://hs-mcp.oga-surf-project.workers.dev/.well-known/agent-card.json, the Cloudflare Workers origin behind
    the custom domain and the URL a2aregistry.org lists as wellKnownURI. The legacy /.well-known/agent.json returns
    a real JSON 404 ({"error":"not_found","known_paths":[…]}, 561 bytes), and a negative-control path
    (/.well-known/horizonshield-negative-control-7e2a91.json) also 404s, so the 200 is a served document, not a
    catch-all. Ownership: provider.organization is "The HORIZ音s株式会社" (this company), provider.url and
    documentationUrl are https://shield.the-horizons-innovation.com, whose JSON-LD Organization node names the same
    company, the same MCP host, and explicitly disclaims the unrelated cybersecurity products at horizonshield.org /
    horizonshield.ai.
x-evidence:
  fetched: '2026-09-19'
  url: https://mcp.horizonshield.dev/.well-known/agent-card.json
  http_status: 200
  content_type: application/json; charset=utf-8
  body_bytes: 9940
  body_parses_as: >-
    JSON object with AgentCard shape (supportedInterfaces, protocolVersion, name, description, url,
    preferredTransport, provider, version, capabilities, defaultInputModes, defaultOutputModes, skills,
    documentationUrl, signatures) plus provider-specific top-level fields compensation, ledger, dataset
  corroborating_probes:
  - url: https://hs-mcp.oga-surf-project.workers.dev/.well-known/agent-card.json
    http_status: 200
    note: Registry-listed copy (a2aregistry.org wellKnownURI). Identical to the mcp-host copy except it carries no signatures[] block (9631 vs 9940 bytes).
  - url: https://mcp.horizonshield.dev/.well-known/agent.json
    http_status: 404
  - url: https://horizonshield.dev/.well-known/agent-card.json
    http_status: 0
    note: Could not resolve host — the apex has no address record on any public resolver.
  - url: https://shield.the-horizons-innovation.com/.well-known/agent-card.json
    http_status: 404
    note: The documentation host (GitHub Pages) serves no card; it returns the GitHub Pages 404 page.
  - url: https://mcp.horizonshield.dev/
    method: POST
    body: '{"jsonrpc":"2.0","id":1,"method":"message/send","params":{"message":{"role":"user","parts":[{"kind":"text","text":"ping"}],"messageId":"apievangelist-probe-1"}}}'
    http_status: 200
    response: 'Task object {"kind":"task","id":"979a8040-…","status":{"state":"completed","message":{"role":"agent","parts":[{"kind":"text","text":"HORIZON SHIELD KIRA / 見積もり誠実性監査 … No known high-pressure tactic matched …"}]}}}'
    note: A real A2A message/send responder on the same URL as the MCP server — the probe text "ping" was run through the red-flag skill and a completed Task came back. Nothing was purchased and no ledger record is created by this skill.
  - url: https://mcp.horizonshield.dev/
    method: POST
    body: '{"jsonrpc":"2.0","id":1,"method":"tasks/get","params":{"id":"apievangelist-nonexistent-probe"}}'
    http_status: 200
    response: '{"jsonrpc":"2.0","id":6,"error":{"code":-32601,"message":"Method not found: tasks/get"}}'
    note: tasks/get is not implemented; the sibling gate and JIDEC agents say so explicitly ("This agent implements SendMessage (1.0) and message/send (0.3)").
  - url: https://mcp.horizonshield.dev/.well-known/jwks.json
    http_status: 200
    note: 'JWKS with one EC P-256 key, kid hs-2026-09, alg ES256, use sig — the key the card''s signatures[0] protected header names via jku.'
  - url: https://a2aregistry.org/api/agents?search=HORIZON
    http_status: 200
    note: The card entered the harvest backlog as one of 415 agents on a2aregistry.org (author "The HORIZ音s株式会社"). The registry was the lead; the card above was fetched from the provider's own host.
agent_card:
  name: HORIZON SHIELD KIRA
  description: >-
    An independent, pre-transaction auditor for construction and renovation estimates. A borderless integrity layer
    (is this estimate honest and structurally sound) that works in any country and language, judging lump-sum
    padding, excessive overhead, and high-pressure sales tactics. Built on 30 years of field experience by a Japanese
    master carpenter. Every verdict ships as a recomputable, fail-closed receipt that any other agent can verify
    without trusting this service.
  url: https://mcp.horizonshield.dev
  version: 1.0.0
  protocol_version: 0.3.0
  preferred_transport: JSONRPC
  supported_interfaces:
  - {url: 'https://mcp.horizonshield.dev', protocolBinding: JSONRPC, protocolVersion: '1.0'}
  - {url: 'https://mcp.horizonshield.dev', protocolBinding: JSONRPC, protocolVersion: '0.3'}
  provider:
    organization: The HORIZ音s株式会社
    url: https://shield.the-horizons-innovation.com
  capabilities:
    streaming: false
    push_notifications: false
    state_transition_history: false
    extensions:
    - uri: https://gate.horizonshield.dev/ext/conduct/v1
      required: false
      description: A2A Conduct Extension v1 — who pays this agent (paid_by buyer, referral_fee false, listing_fee false, success_fee_pct 0), where its measured conduct record lives, and where to file a witness walk. Authored and served by this provider.
  default_input_modes: [text/plain, application/json]
  default_output_modes: [application/json, text/plain]
  security_schemes: null
  security: null
  documentation_url: https://shield.the-horizons-innovation.com
  icon_url: null
  signatures: 1 JWS (ES256, kid hs-2026-09, jku https://mcp.horizonshield.dev/.well-known/jwks.json)
  skill_count: 3
  skills:
  - {id: estimate-integrity-audit, name: Estimate integrity audit (borderless), tags: [construction, estimate, audit, fraud-detection, credence-goods, borderless, price-verification, overcharge-detection, second-opinion, planning-stage], examples: 15}
  - {id: japan-property-reform-intake, name: Japan property acquisition and renovation intake, tags: [japan, real-estate, renovation, intake, takkenshi, cross-border], examples: 4}
  - {id: verify-claim, name: Integrity claim verification (fail closed), tags: [verification, integrity, fail-closed, tamper-evident, a2a, credence-goods], examples: 2}
  provider_specific_fields:
    compensation: {paid_by: buyer, referral_fee: false, listing_fee: false, success_fee_pct: 0, disclosure_url: 'https://shield.the-horizons-innovation.com/verify-directory/'}
    ledger: {name: JIDEC, url: 'https://hs-ledger.oga-surf-project.workers.dev', catalog: 'https://hs-ledger.oga-surf-project.workers.dev/.well-known/api-catalog', mcp: 'https://hs-jidec-mcp.oga-surf-project.workers.dev/mcp'}
    dataset: {name: Japan Construction Cost Database (JCCDB), license: CC BY 4.0, doi: 'https://doi.org/10.5281/zenodo.22127752'}
conformance:
  spec: A2A 1.0.0
  grade: conformant
  protocol_version: '0.3.0'
  preferred_transport: JSONRPC
  hard_checks:
    capabilities_is_object: true
    protocol_version_present: true
    skills_is_array: true
  optional_fields:
    default_input_modes: true
    default_output_modes: true
    preferred_transport: true
  grade_basis: >-
    capabilities is an OBJECT (streaming, pushNotifications, stateTransitionHistory, extensions[]); protocolVersion
    "0.3.0" is present at the top level; skills is an ARRAY of three fully-populated skills (id, name, description,
    tags, examples). All three optional discriminators are present. The card carries BOTH the 0.3.0 triple
    (url + preferredTransport + protocolVersion) and a 1.0-style supportedInterfaces[] block declaring JSONRPC at
    protocolVersion 1.0 and 0.3, so a reader written against either revision finds its fields. It is signed (JWS
    ES256) with a key resolvable from the same host's /.well-known/jwks.json.
  deviations:
  - field: securitySchemes / security
    observed: absent
    note: The agent is anonymous by design (the MCP server, the plugin README and the site all say "no API key"); the card does not say so in the A2A vocabulary, so a client cannot read the auth posture from securitySchemes.
  - field: url / supportedInterfaces[].url
    observed: https://mcp.horizonshield.dev — the same URL as the MCP Streamable HTTP endpoint
    note: One JSON-RPC URL multiplexes MCP methods (initialize, tools/list, tools/call, prompts/*) and A2A methods (message/send). Verified live for both. tasks/get and agent/getAuthenticatedExtendedCard return -32601.
  - field: compensation / ledger / dataset
    observed: provider-specific top-level fields
    note: Not in the A2A schema. compensation duplicates the conduct extension's params so a reader that ignores extensions still sees who pays; ledger and dataset point at the JIDEC ledger and the CC BY 4.0 JCCDB dataset (DOI). The ledger URLs here are the workers.dev origins; the custom domains https://ledger.horizonshield.dev and https://jidec.horizonshield.dev/mcp serve the same services.
  - field: skills[].inputModes / outputModes / security
    observed: absent on every skill
    note: Optional per-skill fields; the card relies on the defaults (text/plain, application/json).
additional_cards:
  note: >-
    The provider serves five more A2A agent cards on its own subdomains, each with the same JWS key id and the same
    conduct extension. All were fetched 2026-09-19, saved verbatim, and graded against the same hard checks. Two of
    the hosts the register also lists (p001 / p002.horizonshield.dev) serve cards whose provider.organization is a
    Yakumo member CONTRACTOR (リフォーム職人株式会社, ミネオトーヨー住器株式会社), not this company — HORIZON SHIELD hosts them
    as its "WebMCP Partner" tier — so they are noted here and not saved as this provider's cards.
  cards:
  - file: a2a/horizonshield-dev-jidec-agent-card.json
    source: https://ledger.horizonshield.dev/.well-known/agent-card.json
    http_status: 200
    bytes: 4464
    name: HORIZON SHIELD JIDEC
    version: 1.1.0
    protocol_version: '0.3.0'
    url: https://ledger.horizonshield.dev/a2a
    skills: 1
    grade: conformant
    signed: true
    notes: >-
      Declares securitySchemes {} and security [] explicitly, supportsAuthenticatedExtendedCard false, and an
      additionalDiscovery block pointing at the RFC 9727 api-catalog and the MCP endpoint https://jidec.horizonshield.dev/mcp.
      A second copy at https://jidec.horizonshield.dev/.well-known/agent-card.json (200, 5076 bytes) names
      https://jidec.horizonshield.dev/a2a as its interface. POST tasks/get on /a2a returns -32601 with the
      message "This agent implements SendMessage (1.0) and message/send (0.3); send a JIDEC citation as a text part."
  - file: a2a/horizonshield-dev-gate-agent-card.json
    source: https://gate.horizonshield.dev/.well-known/agent-card.json
    http_status: 200
    bytes: 4090
    name: MCP Verification Gate
    version: 0.4.7
    protocol_version: '0.3.0'
    url: https://gate.horizonshield.dev/a2a
    skills: 2
    grade: conformant
    signed: true
    notes: The card is also declared as a path in the gate's own OpenAPI (GET /.well-known/agent-card.json). POST tasks/get on /a2a returns -32601 naming SendMessage (1.0) and message/send (0.3).
  - file: a2a/horizonshield-dev-yakumo-agent-card.json
    source: https://hearing.horizonshield.dev/.well-known/agent-card.json
    http_status: 200
    bytes: 2589
    name: HORIZON SHIELD YAKUMO
    version: null
    protocol_version: '0.3.0'
    url: https://hearing.horizonshield.dev/mcp
    skills: 1
    grade: conformant
    signed: false
    notes: 'Passes every hard and optional check but omits version and points url at the MCP endpoint; its conduct extension declares paid_by seller / listing_fee true — the one surface in the family that is seller-funded (the Yakumo mall membership plans).'
  - file: a2a/horizonshield-dev-femtech-agent-card.json
    source: https://femtech.horizonshield.dev/.well-known/agent-card.json
    http_status: 200
    bytes: 5595
    name: HORIZON SHIELD Femtech Registry
    version: 0.4.1
    protocol_version: '0.3.0'
    url: https://femtech.horizonshield.dev/a2a
    skills: 2
    grade: conformant
    signed: true
    notes: A second product line (neutral femtech information-source registry) run by the same company; carries extra top-level fields (protocol, role, mcp_endpoint, discovery, medical_disclaimer).
  - file: a2a/horizonshield-dev-webmcp-agent-card.json
    source: https://web.horizonshield.dev/.well-known/agent-card.json
    http_status: 200
    bytes: 4425
    name: 'HORIZON SHIELD: Construction Estimate Auditor for Japan (KIRA)'
    version: 1.0.4
    protocol_version: null
    url: null
    skills: 5
    grade: flavored
    signed: false
    notes: 'Fails the protocolVersion hard check and has no url / supportedInterfaces / preferredTransport / default modes; it is a WebMCP intake descriptor wearing the agent-card path (keys: capabilities, protocol, name, provider, description, compensation, version, role, skills, bridges_to, how_to_connect, site). skills[] entries are the five MCP tool names without ids.'
surface_relationship:
  note: >-
    One company, one signing key (kid hs-2026-09, one JWKS per host), six agent cards. KIRA (mcp.) is the product:
    price audit + verifiable receipts + AP2 attestation. JIDEC (ledger./jidec.) is the audit-of-the-auditor: an
    append-only, Bitcoin-anchored ledger with an RFC 9727 api-catalog. The gate (gate.) is a public conformance
    register for OTHER people's MCP servers, with the only OpenAPI in the family. Yakumo (hearing.) is the verified
    contractor directory. WebMCP (web.) is an intake desk. Femtech (femtech.) is a separate registry product. Every
    card declares the same A2A Conduct Extension, whose specification the company itself serves at
    https://gate.horizonshield.dev/ext/conduct/v1 — see conformance/horizonshield-dev-conformance.yml.