# Ethereum Mainnet JSON-RPC via x402 (Pay-per-call)

> Ethereum Mainnet JSON-RPC via x402 (Pay-per-call) 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 2026-10-31).

Executes Ethereum mainnet JSON-RPC calls (eth_call, eth_getBalance, etc.) on a pay-per-call basis using Base USDC via the x402 protocol, with no API key required.

## Facts

- Endpoint: GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/eth-rpc?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ethereum-mainnet-json-rpc-via-x402-pay-per-call-e6053aa0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KkAkx29TKFlcxRwhso4eR

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 ethereum-mainnet-json-rpc-via-x402-pay-per-call-e6053aa0
```

Example prompt: What's the current ETH balance of 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Ethereum mainnet? Use eth_getBalance with 'latest' block — pay per call with USDC on Base.

## When to prefer this

Choose this endpoint when your AI agent needs to read Ethereum mainnet state (balances, contract data, receipts) without setting up an Alchemy/Infura account, especially in agentic pay-per-call workflows using x402/USDC micropayments. Batch up to 10 calls for a single $0.002 payment, making it significantly cheaper than comparable x402 RPC APIs at ~$0.01/call. Ideal for autonomous agents that need occasional Ethereum data without subscription overhead.

## Known failure modes

- Invalid JSON-RPC method name returns an error object with code and message
- Malformed params array causes a parse error response
- Calling a non-existent contract method may return 0x or revert
- Payment not received or insufficient USDC results in 402 Payment Required
- Rate limits or upstream node unavailability may cause transient 503 errors
- eth_sendRawTransaction and write methods are not supported (read-only)

## How this service works

Pay-per-call Ethereum mainnet (chain 1) JSON-RPC, no API key, no account, paid in Base USDC: GET ?method=eth_call&params=[...] or POST a standard JSON-RPC body; POST a batch of up to 10 calls for ONE $0.002 payment (vs ~$0.01 per call at other x402 mainnet RPC APIs). Methods: eth_blockNumber, eth_chainId, eth_call, eth_estimateGas, eth_getBalance, eth_getTransactionCount, eth_getCode, eth_getStorageAt, eth_getTransactionByHash, eth_getTransactionReceipt, eth_getBlockByNumber,...

## Output

A JSON-RPC 2.0 response object containing: id, jsonrpc version, the result field (hex-encoded or structured data depending on method), chain name ('ethereum'), chain_id (1), the upstream RPC URL used, and 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/ethereum-mainnet-json-rpc-via-x402-pay-per-call-e6053aa0/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)