# Phantom API — Arbitrum RPC Endpoint

> Phantom API — Arbitrum RPC Endpoint is a paid API for AI agents from phantom-api-omega.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Provides pay-per-call JSON-RPC access to the Arbitrum network, enabling blockchain data queries and smart contract interactions on Arbitrum via the standard Ethereum RPC interface.

## Facts

- Endpoint: POST https://phantom-api-omega.vercel.app/api/arbitrum/rpc
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/phantom-api-arbitrum-rpc-endpoint-0206fb83
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_r0dMHXj95wmrrNsXJIgSk

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 phantom-api-arbitrum-rpc-endpoint-0206fb83 -d '<json body>'
```

Example prompt: What is the current ETH balance of wallet address 0xABC...123 on Arbitrum? Use eth_getBalance with the latest block tag.

## When to prefer this

Choose this endpoint when you need pay-per-call, no-subscription Arbitrum RPC access billed in USDC via x402 micro-payments — ideal for agents that make sporadic or low-volume on-chain queries without committing to a monthly RPC plan. Prefer over free public endpoints when reliability and response speed matter.

## Known failure modes

- Invalid JSON-RPC method name returns an error object with code -32601
- Malformed params array causes -32602 invalid params error
- Payment failure (insufficient x402 balance) blocks the request before it reaches the RPC node
- Network congestion or node unavailability may cause timeouts
- Calls to non-existent contracts return 0x or empty data without explicit error

## How this service works

Lightning-fast access to blockchain data, smart contract insights, and Web3 infrastructure across 57+ networks. Pay-per-call via x402.

## Output

Returns standard Ethereum JSON-RPC response objects containing requested blockchain data such as balances (in wei), block objects, transaction receipts, smart contract return values, gas estimates, or event logs, depending on the method called.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "method": {
   "type": "string"
  },
  "params": {
   "type": "array",
   "items": {}
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/phantom-api-arbitrum-rpc-endpoint-0206fb83/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from phantom-api-omega.vercel.app](https://www.zero.xyz/host/phantom-api-omega.vercel.app/llms.txt)