# Phantom API – Optimism Token Balances

> Phantom API – Optimism Token Balances 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 2026-10-20).

Fetches ERC-20 token balances for a given wallet address on the Optimism network, optionally filtered by specific contract addresses.

## Facts

- Endpoint: POST https://phantom-api-omega.vercel.app/api/optimism/token/balances?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/phantom-api-optimism-token-balances-a52be399
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kc5hCI8rcCL5g10T9XsSi

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-optimism-token-balances-a52be399 -d '<json body>'
```

Example prompt: What ERC-20 token balances does wallet 0xAbC...123 hold on Optimism — check all tokens, or just these two contracts: 0xToken1 and 0xToken2?

## When to prefer this

Use this endpoint when you specifically need ERC-20 token balance data on the Optimism L2 network. Prefer it over generic multi-chain endpoints when Optimism is the target chain, and over Ethereum mainnet endpoints when querying Optimism-native or bridged tokens. Its pay-per-call model via x402 makes it suitable for low-frequency or agent-driven queries without subscription overhead.

## Known failure modes

- Invalid or malformed owner address returns an error or empty result
- Invalid contract addresses in the array may be ignored or cause a validation error
- Wallet with no token balances returns an empty list
- Payment failure (x402) blocks the request before execution
- Rate limiting or network issues on the Optimism RPC layer may cause timeouts

## 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 a list of token balances associated with the specified wallet address on Optimism, including token contract addresses and balance amounts. When specific contract addresses are provided, results are filtered to those tokens only.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "owner": {
   "type": "string"
  },
  "contractAddresses": {
   "type": "array",
   "items": {
    "type": "string"
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/phantom-api-optimism-token-balances-a52be399/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)