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facilitator.ultravioletadao.xyz · 2026-09-19 06:06:07 UTC · 875837ca5e73286a4bbbba3c9a66675b8f85ccbae158fd9f7c61e9410015fc25

This is a frozen copy of the agent's agent-card.json as we observed it at the timestamp above. We capture a new snapshot every time the card's content hash changes. Useful for: forensic drift analysis, verifying downstream callers see the right version, reproducing routing decisions made historically.

{
  "name": "Ultravioleta DAO x402 Facilitator",
  "version": "1.0.0",
  "description": "x402 payment facilitator operated by Ultravioleta DAO. Verifies and settles signed payments with sponsored network fees, including Arc USDC mainnet/testnet and native Hedera HBAR/USDC mainnet/testnet. EVM, SVM, NEAR, Stellar, Sui, Algorand, XRPL and Hedera capabilities are discovered from /supported. Hedera uses x402 v2/exact only; Arc uses direct EOA exact v1/v2. No facilitator fee. ERC-8004 identity/reputation and Bazaar discovery have their own network scopes.",
  "url": "https://facilitator.ultravioletadao.xyz/",
  "preferredTransport": "HTTP+JSON",
  "additionalInterfaces": [
    {
      "url": "https://facilitator.ultravioletadao.xyz/",
      "transport": "HTTP+JSON"
    },
    {
      "url": "https://facilitator.ultravioletadao.xyz/mcp",
      "transport": "MCP+STREAMABLE-HTTP"
    }
  ],
  "supportedInterfaces": [
    {
      "url": "https://facilitator.ultravioletadao.xyz/",
      "transport": "HTTP+JSON"
    },
    {
      "url": "https://facilitator.ultravioletadao.xyz/mcp",
      "transport": "MCP+STREAMABLE-HTTP"
    }
  ],
  "documentationUrl": "https://facilitator.ultravioletadao.xyz/skill.md",
  "capabilities": [
    {
      "id": "x402-verification",
      "name": "Verify x402 payment authorizations",
      "description": "Validate network-specific signatures, amounts, accounts/tokens and validity windows without submitting a transfer. Native Hedera inspects buyer-signed CryptoTransfer bytes and HTS account eligibility."
    },
    {
      "id": "x402-settlement",
      "name": "Settle x402 payments on-chain",
      "description": "Submit a verified authorization and return the transaction hash or native Hedera transaction ID. The facilitator pays network fees."
    },
    {
      "id": "erc8004-identity-reputation",
      "name": "ERC-8004 Trustless Agents",
      "description": "Read and write on-chain agent identity and reputation on 12 mainnets (21 networks including testnets)."
    },
    {
      "id": "mcp-tools",
      "name": "MCP server (Streamable HTTP)",
      "description": "The same verify / settle / supported / accepts calls exposed as MCP tools at POST /mcp: x402_supported, x402_accepts, x402_verify, x402_settle. Stateless transport, no authentication, and every tool dispatched through the REST handler it names. Server card: /.well-known/mcp/server-card.json."
    }
  ],
  "skills": [
    {
      "id": "verify-payment",
      "name": "Verify a payment authorization",
      "description": "POST /verify. Answers HTTP 200 with {\"isValid\": true|false}; a rejected payment is still a 200, so branch on the body, not the status code.",
      "tags": [
        "x402",
        "verify",
        "eip-3009",
        "payments"
      ],
      "examples": [
        "Is this signed USDC authorization on Base valid for these payment requirements?"
      ],
      "inputModes": [
        "application/json"
      ],
      "outputModes": [
        "application/json"
      ]
    },
    {
      "id": "settle-payment",
      "name": "Settle a payment on-chain",
      "description": "POST /settle re-verifies and submits the network-native transfer. Read success and transaction in the response; Hedera returns account@seconds.nanoseconds. Arc/Hedera support exact only; other schemes depend on the advertised network.",
      "tags": [
        "x402",
        "settle",
        "on-chain",
        "gasless"
      ],
      "examples": [
        "Settle this authorization on Base and give me the transaction hash."
      ],
      "inputModes": [
        "application/json"
      ],
      "outputModes": [
        "application/json"
      ]
    },
    {
      "id": "list-supported",
      "name": "List supported networks and schemes",
      "description": "GET /supported returns the enabled (version, scheme, network) capabilities and network-specific fee payers. Legacy/CAIP-2 aliases may coexist; Hedera is native v2 only.",
      "tags": [
        "x402",
        "discovery",
        "networks",
        "caip-2"
      ],
      "examples": [
        "Which chains and stablecoins can this facilitator settle on right now?"
      ],
      "inputModes": [
        "application/json"
      ],
      "outputModes": [
        "application/json"
      ]
    },
    {
      "id": "negotiate-accepts",
      "name": "Negotiate payment requirements",
      "description": "POST /accepts. Enriches a seller's draft payment requirements with the facilitator's fee payer, token list and escrow data. Faremeter-middleware compatible.",
      "tags": [
        "x402",
        "402-challenge",
        "faremeter"
      ],
      "examples": [
        "Fill in the token list and fee payer for this 402 challenge on Base."
      ],
      "inputModes": [
        "application/json"
      ],
      "outputModes": [
        "application/json"
      ]
    }
  ],
  "defaultInputModes": [
    "application/json"
  ],
  "defaultOutputModes": [
    "application/json"
  ],
  "provider": {
    "organization": "Ultravioleta DAO",
    "url": "https://ultravioletadao.xyz",
    "contactEmail": "ultravioletadao@gmail.com"
  }
}