# Crypto Microdata for Agents (x402) — Ethereum Mainnet RPC

> Crypto Microdata for Agents (x402) — Ethereum Mainnet RPC is a paid API for AI agents from kr-x402-mvp.kgy5612.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-11-02).

Executes Ethereum mainnet JSON-RPC calls (balances, gas, eth_call, etc.) via pay-per-call x402 micropayments with no API key required

## Facts

- Endpoint: GET https://kr-x402-mvp.kgy5612.workers.dev/api/v1/rpc/mainnet?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/crypto-microdata-for-agents-x402-ethereum-mainnet-rpc-513bd1ba
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Nu8C3FZjXGQhUI9ddhyht

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-ethereum-mainnet-rpc-513bd1ba
```

Example prompt: Check the current ETH balance of wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Ethereum mainnet using the eth_getBalance RPC method — pay the micro-fee in USDC, no API key needed.

## When to prefer this

Choose this endpoint when your AI agent needs raw Ethereum mainnet JSON-RPC access without managing API keys or monthly subscriptions — ideal for autonomous agents that pay per-call in USDC via x402. Best for lightweight, read-only RPC calls (eth_getBalance, eth_blockNumber, eth_call) in DeFi trading or onchain automation contexts.

## Known failure modes

- Payment not provided or insufficient USDC via x402 — returns 402 Payment Required
- Invalid JSON-RPC method name — upstream may return an error result field
- Malformed params array (not valid URL-encoded JSON) — may cause upstream parse error
- Upstream publicnode.com outage — elevated latency or 5xx response
- Calling write methods (eth_sendRawTransaction) may not be supported on a GET endpoint

## 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

A JSON-RPC 2.0 response object containing: the method result (e.g. hex balance, hex block number, or call return data), the chain name ('ethereum'), chain_id (1), the upstream RPC URL used, and the latency in milliseconds.

## 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": {
      "method": {
       "type": "string",
       "examples": [
        "eth_blockNumber",
        "eth_getBalance",
        "eth_call"
       ],
       "description": "JSON-RPC method (default eth_blockNumber)"
      },
      "params": {
       "type": "string",
       "examples": [
        "[]",
        "[\"0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045\",\"latest\"]"
       ],
       "description": "URL-encoded JSON array of params (default [])"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "id": 1,
  "chain": "ethereum",
  "result": "0x16a3f2b",
  "jsonrpc": "2.0",
  "chain_id": 1,
  "upstream": "https://ethereum-rpc.publicnode.com",
  "latency_ms": 92
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/crypto-microdata-for-agents-x402-ethereum-mainnet-rpc-513bd1ba/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)