# Crypto Microdata for Agents (x402) — /pay Gateway

> Crypto Microdata for Agents (x402) — /pay Gateway is a paid API for AI agents from kr-x402-mvp.kgy5612.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-31).

Pay-per-call gateway endpoint that accepts x402 micropayments (USDC on Base) and returns routing metadata and receipt for subsequent crypto data calls

## Facts

- Endpoint: GET https://kr-x402-mvp.kgy5612.workers.dev/pay?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/crypto-microdata-for-agents-x402-pay-gateway-3e5844e6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_BjIkmfecpuB3ynLaXChb-

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability crypto-microdata-for-agents-x402-pay-gateway-3e5844e6
```

Example prompt: Pay for a crypto microdata call using x402 with my USDC on Base and tag it with correlation ID 'run-001' so I can verify the payment went through before fetching Base gas prices.

## When to prefer this

Use this endpoint as the mandatory first step when integrating with the x402 crypto microdata suite — it handles payment verification and returns routing metadata so your agent knows which data endpoints to call next. Prefer it over API-key-based crypto data services when you want keyless, pay-per-call access with USDC on Base, or when building onchain agents that need to self-fund their own data access programmatically.

## Known failure modes

- Payment not received or insufficient USDC balance — returns 402 Payment Required with payment instructions
- Invalid x402 payment header format — returns 400 Bad Request
- echo or testRunId exceeds max length (64 or 100 chars) — schema validation error
- Network or Cloudflare Worker timeout — returns 5xx with no receipt
- Payment double-spend or replay detected — payment rejected

## How this service works

Pay-per-call crypto microdata for trading/onchain AI agents via x402 (USDC on Base): Base gas, token risk, balances, multi-venue prices, Hyperliquid book/funding, kimchi premium. No API keys.

## Output

Returns a JSON object with: timestamp (t), ok status, paymentVerified boolean, receiptId for the micropayment, echoed testRunId, nextAction string ('call_paid_data'), and an array of suggested next endpoint paths (e.g. /crypto/base-gas, /crypto/liquidations).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "echo": {
       "type": "string",
       "examples": [
        "my-agent-1"
       ],
       "maxLength": 64,
       "description": "Optional string echoed back (correlate your test call)"
      },
      "testRunId": {
       "type": "string",
       "examples": [
        "run-001"
       ],
       "maxLength": 100,
       "description": "Optional caller-supplied correlation ID for a bounded validation run (echoed back)"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "t": "2026-10-28T14:00:00Z",
  "ok": true,
  "next": [
   "/crypto/simulate",
   "/crypto/ens",
   "/crypto/liquidations?coin=BTC",
   "/crypto/base-gas"
  ],
  "receiptId": "rcpt_0b9f6c1e2a7d4c55",
  "testRunId": "run-001",
  "nextAction": "call_paid_data",
  "paymentVerified": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/crypto-microdata-for-agents-x402-pay-gateway-3e5844e6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from kr-x402-mvp.kgy5612.workers.dev](https://www.zero.xyz/host/kr-x402-mvp.kgy5612.workers.dev/llms.txt)