{
  "name": "x402 Discovery API",
  "description": "Discover x402-compatible services that accept USDC payments. Search and filter services by protocol type, blockchain network, payment requirements, and price.",
  "version": "2.0.0",
  "provider": "Circle",
  "capabilities": [
    "Service discovery",
    "Payment information retrieval",
    "Schema validation",
    "Price filtering",
    "Network filtering"
  ],
  "endpoints": [
    {
      "path": "/v2/x402/discovery/resources",
      "method": "GET",
      "description": "List all x402-compatible discovery resources with payment information",
      "baseUrl": "https://api.circle.com",
      "parameters": [
        {
          "name": "query",
          "type": "string",
          "in": "query",
          "required": false,
          "description": "Fuzzy search across resource URLs, providers, descriptions, and categories"
        },
        {
          "name": "type",
          "type": "string",
          "in": "query",
          "required": false,
          "description": "Filter by protocol type (http, mcp)",
          "enum": [
            "http",
            "mcp"
          ]
        },
        {
          "name": "network",
          "type": "string",
          "in": "query",
          "required": false,
          "description": "Filter by blockchain network. Accepts CAIP-2 format (e.g., eip155:8453) or legacy SDK names (e.g., base, base-sepolia)"
        },
        {
          "name": "maxUsdPrice",
          "type": "number",
          "in": "query",
          "required": false,
          "description": "Maximum price per request in USD (e.g., 0.01 for services under 1 cent)"
        },
        {
          "name": "limit",
          "type": "integer",
          "in": "query",
          "required": false,
          "description": "Maximum results to return (default: 50, max: 200)",
          "default": 50
        },
        {
          "name": "offset",
          "type": "integer",
          "in": "query",
          "required": false,
          "description": "Number of results to skip for pagination",
          "default": 0
        }
      ]
    },
    {
      "path": "/v1/x402/discovery/resources",
      "method": "GET",
      "description": "Legacy v1 endpoint (output schema in accepts array)",
      "baseUrl": "https://api.circle.com"
    }
  ],
  "authentication": {
    "type": "none",
    "description": "Public API - no authentication required for read access"
  },
  "pricing": {
    "type": "free",
    "description": "Free to use for discovery. Individual services may require payment."
  },
  "documentation": {
    "quickstart": "https://agents.circle.com/SKILL.md",
    "skillsIndex": "https://agents.circle.com/.well-known/agent-skills/index.json",
    "fullContext": "https://agents.circle.com/llms-full.txt",
    "apiReference": "https://agents.circle.com/.well-known/openapi.json",
    "serviceDiscovery": "https://agents.circle.com/services/llms.txt",
    "protocol": "https://developers.circle.com/gateway/nanopayments/concepts/x402"
  },
  "contact": {
    "name": "Circle Developer Support",
    "url": "https://developers.circle.com/gateway/nanopayments/concepts/x402"
  },
  "links": [
    {
      "rel": "self",
      "href": "https://agents.circle.com/.well-known/a2a.json"
    },
    {
      "rel": "service",
      "href": "https://api.circle.com/v2/x402/discovery/resources"
    },
    {
      "rel": "documentation",
      "href": "https://agents.circle.com/.well-known/openapi.json"
    },
    {
      "rel": "agent-skills",
      "href": "https://agents.circle.com/.well-known/agent-skills/index.json"
    },
    {
      "rel": "full-context",
      "href": "https://agents.circle.com/llms-full.txt"
    }
  ]
}