ERC-8004 Agent Liveness

{
  "name": "ERC-8004 Agent Liveness",
  "description": "Checks whether an ERC-8004-registered agent is actually alive right now, not just registered once.",
  "url": "https://erc8004-agent-liveness-325572559480.us-central1.run.app",
  "version": "1.0.0",
  "documentationUrl": "https://erc8004-agent-liveness-325572559480.us-central1.run.app/docs",
  "provider": {
    "organization": "nexus-mcp-infra",
    "url": "https://github.com/nexus-mcp-infra"
  },
  "capabilities": {
    "streaming": false,
    "pushNotifications": false,
    "stateTransitionHistory": false
  },
  "defaultInputModes": [
    "application/json"
  ],
  "defaultOutputModes": [
    "application/json"
  ],
  "additionalInterfaces": [
    {
      "url": "https://erc8004-agent-liveness-325572559480.us-central1.run.app/mcp",
      "transport": "MCP"
    }
  ],
  "skills": [
    {
      "id": "nexus_erc8004_agent_liveness_verify_registered_agent",
      "name": "Verify Registered Agent Liveness",
      "description": "Check whether an ERC-8004-registered agent is actually alive right now via a real MCP handshake against its declared endpoint.",
      "tags": [
        "erc-8004",
        "agent-identity",
        "liveness",
        "trust",
        "web3"
      ]
    }
  ],
  "metadata": {
    "protocol_note": "This service implements the Model Context Protocol (MCP) at /mcp, not A2A's own task methods. POST /verify-registered-agent is charged $0.10 via x402 (Base Sepolia TESTNET, not real funds); the MCP tool is currently free -- see README. Payment settles BEFORE this handler runs: a call is charged even on AGENT_NOT_FOUND or a 422. Checks the real ERC-8004 Identity Registry on Base Sepolia testnet -- no exclusive data access, the value is the real-time MCP liveness check a raw registry lookup can't give you."
  }
}