MCP Verification Gate

{
  "name": "MCP Verification Gate",
  "description": "Checks whether an MCP server exists, publishes an agent card, discloses who pays it, and returns identical output for identical input. Free. Conformance and disclosure only; this gate does not verify that any price returned by a checked server is correct.",
  "supportedInterfaces": [
    {
      "url": "https://gate.horizonshield.dev/a2a",
      "protocolBinding": "JSONRPC",
      "protocolVersion": "1.0"
    },
    {
      "url": "https://gate.horizonshield.dev/a2a",
      "protocolBinding": "JSONRPC",
      "protocolVersion": "0.3"
    }
  ],
  "url": "https://gate.horizonshield.dev/a2a",
  "provider": {
    "organization": "The HORIZ\u97f3s Co., Ltd."
  },
  "version": "0.4.7",
  "protocolVersion": "0.3.0",
  "capabilities": {
    "streaming": false,
    "pushNotifications": false,
    "extensions": [
      {
        "uri": "https://gate.horizonshield.dev/ext/conduct/v1",
        "description": "Who pays this agent, where its measured conduct record lives, and where to file a witness walk. The specification is served at the URI.",
        "required": false,
        "params": {
          "compensation": {
            "paid_by": "buyer",
            "referral_fee": false,
            "listing_fee": false,
            "success_fee_pct": 0,
            "disclosure_url": "https://shield.the-horizons-innovation.com/yakumo/plans/"
          },
          "measured_endpoints": [
            "https://gate.horizonshield.dev/mcp"
          ],
          "conduct_record": "https://gate.horizonshield.dev/history?endpoint=https%3A%2F%2Fgate.horizonshield.dev%2Fmcp",
          "verdict_recipe": "https://gate.horizonshield.dev/spec",
          "witness_intake": "https://ledger.horizonshield.dev/witness",
          "register": "https://gate.horizonshield.dev/register",
          "rings": {
            "spec": "https://github.com/ogasurfproject-jpg/horizon-shield/blob/main/workers/hs-ledger/nenrin/NENRIN_SPEC_v1.md",
            "spec_sha256": "9ccba2e325fd2a555fcdb2dec519b8c6bf7a669064674846aea98ecfff824e3d",
            "base": "https://raw.githubusercontent.com/ogasurfproject-jpg/mcp-conduct-register/main/rings/",
            "path": "<slug>/<YYYY-MM>.json",
            "slug": "endpoint URL without https://, lower case, every run of characters outside [a-z0-9] replaced by one hyphen, hyphens trimmed at both ends",
            "ledger": "https://ledger.horizonshield.dev/ledger"
          }
        }
      }
    ]
  },
  "defaultInputModes": [
    "text/plain"
  ],
  "defaultOutputModes": [
    "application/json",
    "text/plain"
  ],
  "compensation": {
    "paid_by": "buyer",
    "referral_fee": false,
    "listing_fee": false,
    "success_fee_pct": 0,
    "disclosure_url": "https://shield.the-horizons-innovation.com/yakumo/plans/"
  },
  "preferredTransport": "JSONRPC",
  "skills": [
    {
      "id": "check",
      "name": "Conformance check",
      "description": "POST /check with an MCP endpoint URL, or call the check_conformance tool over MCP at /mcp. Returns a verdict with a recomputable SHA-256. Over A2A (SendMessage at /a2a), a text part carrying an MCP endpoint URL returns this gate's current register reading for it (the same bytes as GET /is-verified): verified true only on a full pass, null otherwise, never false.",
      "tags": [
        "mcp",
        "verification",
        "conformance",
        "disclosure"
      ]
    },
    {
      "id": "verify",
      "name": "Verdict verification",
      "description": "Recompute the SHA-256 of a verdict this gate issued, so you do not have to trust the issuer. Available as the verify_verdict tool over MCP.",
      "tags": [
        "verification",
        "tamper-evident",
        "recomputable"
      ]
    }
  ],
  "signatures": [
    {
      "protected": "eyJhbGciOiJFUzI1NiIsInR5cCI6IkpPU0UiLCJraWQiOiJocy0yMDI2LTA5Iiwiamt1IjoiaHR0cHM6Ly9nYXRlLmhvcml6b25zaGllbGQuZGV2Ly53ZWxsLWtub3duL2p3a3MuanNvbiJ9",
      "signature": "YdfpE2yp-vrrz0WgabcMIkX6rkHRKFFa2e4RNcrfoAjfqG3O6eSDBwueJhmRu3jffiHanNxZadJBkESgksmRPw"
    }
  ]
}