# x402-gateway: cross_chain_balance

> x402-gateway: cross_chain_balance is a paid API for AI agents from x402.freeq.one, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-16).

Fetches the token balances of a wallet address across multiple blockchain networks in a single call

## Facts

- Endpoint: POST https://x402.freeq.one/tools/cross_chain_balance
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-gateway-cross-chain-balance-6f28fa20
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jZquJ4bF2poIlZ8HhJKlT

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 x402-gateway-cross-chain-balance-6f28fa20 -d '<json body>'
```

Example prompt: What token balances does wallet 0xAbC1234...5678 hold across Ethereum, Base, and Polygon? Show me everything including small balances.

## When to prefer this

Choose this endpoint when you need to aggregate a wallet's token holdings across multiple blockchain networks in a single API call rather than querying each chain separately. It is ideal for portfolio dashboards, whale tracking, DeFi analytics, and any scenario requiring a unified multichain balance view. Prefer it over single-chain balance APIs when the user or address may hold assets on more than one network. The pay-per-call x402 model ($0.002 USDC) means no subscription is needed for occasional lookups.

## Known failure modes

- Invalid or malformed wallet address returns an error
- Unsupported chain requested returns partial results or error for that chain
- Payment not fulfilled via x402 results in 402 Payment Required response
- Wallet has no holdings on requested chains returns empty balance lists
- Network timeout on one or more chains may return partial data
- Rate limiting or provider downtime may cause transient failures

## How this service works

x402-gateway tool: cross_chain_balance

## Output

Returns a structured breakdown of token balances held by the specified wallet address across multiple blockchains, including token symbols, amounts, chain names, and optionally USD values for each holding.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chains": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "description": "Chains to query: eth, arb, base, polygon, opt"
  },
  "address": {
   "type": "string",
   "description": "Ethereum address"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {}
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-gateway-cross-chain-balance-6f28fa20/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.freeq.one](https://www.zero.xyz/host/x402.freeq.one/llms.txt)