# QuickNode JSON-RPC Proxy — Fuel Sepolia Testnet

> QuickNode JSON-RPC Proxy — Fuel Sepolia Testnet is a paid API for AI agents from x402.quicknode.com, paid per call via x402, $10/call, status unknown (last checked 2026-09-14).

Routes JSON-RPC calls to the Fuel blockchain Sepolia testnet via QuickNode's node infrastructure

## Facts

- Endpoint: POST https://x402.quicknode.com/fuel-sepolia/
- Price: $10/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/quicknode-da2a5634
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_x7oNK0b3FpBdOSV9xM42_

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-da2a5634 -d '<json body>'
```

Example prompt: Send a JSON-RPC call to the Fuel Sepolia testnet using method 'eth_blockNumber' with an empty params array and request ID 1 — I need to know the current block height on Fuel's test network.

## When to prefer this

Use this endpoint when you need to interact specifically with the Fuel Sepolia testnet (not mainnet) via JSON-RPC, such as during development, testing smart contracts, or validating transactions in a test environment without risking real assets. Prefer this over generic Ethereum RPC endpoints when targeting Fuel's FuelVM-specific methods.

## Known failure modes

- Invalid JSON-RPC method name returns error code -32601 (Method not found)
- Malformed params array returns error code -32602 (Invalid params)
- Payment failure or insufficient funds returns HTTP 402
- Network congestion may cause timeouts on heavy RPC calls
- Testnet node downtime returns 503 Service Unavailable

## How this service works

JSON-RPC proxy — fuel-sepolia

## Output

Returns a standard JSON-RPC 2.0 response object containing the result of the requested method call (e.g. block number, transaction receipt, call return value) or an error object with code and message if the call failed.

## 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-da2a5634/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)