# Aether Base ETH Balance Lookup

> Aether Base ETH Balance Lookup is a paid API for AI agents from aether-x402.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-12).

Returns the ETH balance (in ETH and wei) for a given Base network wallet address, paid via x402 micropayment in USDC.

## Facts

- Endpoint: POST https://aether-x402.vercel.app/v1/base/balance?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/aether-base-eth-balance-lookup-0ecdfedb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-igZebcFpnCxs0Ot_kME0

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 aether-base-eth-balance-lookup-0ecdfedb -d '<json body>'
```

Example prompt: Can you check how much ETH the wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 has on the Base network right now?

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call ETH balance check on the Base L2 network without setting up your own RPC node or managing API keys. It is ideal for AI agents that operate with USDC on Base and need to make onchain queries at minimal cost ($0.001 per call). Prefer this over self-hosted RPC solutions when you want zero infrastructure overhead and native x402 micropayment integration.

## Known failure modes

- Invalid address format (not a valid 0x-prefixed 40-hex-character address) returns a validation error
- Payment failure via x402 if USDC balance is insufficient or x402 handshake fails
- Address not found or zero balance may return 0 ETH without error
- Rate limiting or RPC backend unavailability may cause timeout or 5xx error
- Querying a mainnet Ethereum address that has no Base activity returns 0 balance

## How this service works

Pay-per-call Base onchain data, token risk verdicts and x402 payability audits over x402 (USDC on Base).

## Output

Returns a JSON object containing the wallet's ETH balance as a human-readable decimal string (e.g. '0.001'), the raw wei amount as a string, and the queried wallet address. Response reflects current onchain state on the Base L2 network.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "address": {
   "type": "string",
   "pattern": "^0x[0-9a-fA-F]{40}$"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "eth": "0.001",
  "wei": "1000000000000000",
  "address": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/aether-base-eth-balance-lookup-0ecdfedb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from aether-x402.vercel.app](https://www.zero.xyz/host/aether-x402.vercel.app/llms.txt)