# QuickNode JSON-RPC Proxy — Kaia Kairos Testnet

> QuickNode JSON-RPC Proxy — Kaia Kairos Testnet is a paid API for AI agents from x402.quicknode.com, paid per call via x402, $10/call, status unknown (last checked 2026-09-13).

Proxies JSON-RPC calls to the Kaia Kairos testnet blockchain network via QuickNode infrastructure

## Facts

- Endpoint: POST https://x402.quicknode.com/kaia-kairos/
- Price: $10/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/quicknode-5e6f43b5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_753hFCNFy5lB7IL1xoz1N

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 quicknode-5e6f43b5 -d '<json body>'
```

Example prompt: Can you call eth_getBalance on the Kaia Kairos testnet for address 0xAbC123... using JSON-RPC 2.0 and tell me the current balance?

## When to prefer this

Use this endpoint when you need to interact specifically with the Kaia Kairos testnet (Kaia's test network) via standard JSON-RPC. Prefer this over generic Ethereum RPC endpoints when your smart contracts or dApps are deployed on Kaia Kairos, or when you need to test Kaia-specific features. Choose this over self-hosted nodes when you need reliable, managed RPC infrastructure without node maintenance.

## Known failure modes

- Invalid JSON-RPC method name returns error code -32601 (method not found)
- Malformed params array causes -32602 (invalid params) error
- Network or node unavailability returns 503 or timeout
- Insufficient USDC balance causes payment failure before the call reaches the node
- Testnet-specific methods may differ from mainnet equivalents
- eth_sendRawTransaction with invalid signature returns transaction rejection error

## How this service works

JSON-RPC proxy — kaia-kairos

## Output

Returns a standard JSON-RPC 2.0 response object containing the result of the requested blockchain method (e.g. block data, transaction receipts, account balances, contract call results) or an error object if the call fails. The response includes the matching request ID, jsonrpc version '2.0', and the method-specific result payload.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "jsonrpc",
  "method"
 ],
 "properties": {
  "id": {
   "type": [
    "number",
    "string"
   ],
   "description": "Request identifier"
  },
  "method": {
   "type": "string",
   "description": "JSON-RPC method name (e.g., eth_blockNumber, eth_call)"
  },
  "params": {
   "type": "array",
   "description": "Method parameters"
  },
  "jsonrpc": {
   "type": "string",
   "const": "2.0"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "id": {
   "type": [
    "number",
    "string"
   ]
  },
  "error": {
   "type": "object",
   "properties": {
    "code": {
     "type": "integer"
    },
    "message": {
     "type": "string"
    }
   }
  },
  "result": {
   "description": "RPC result (type varies by method)"
  },
  "jsonrpc": {
   "type": "string",
   "const": "2.0"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/quicknode-5e6f43b5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.quicknode.com](https://www.zero.xyz/host/x402.quicknode.com/llms.txt)