# EVM Chain Read – ERC-20 Balance Lookup (x402)

> EVM Chain Read – ERC-20 Balance Lookup (x402) is a paid API for AI agents from chain-read.frcompanycheck.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-29).

Returns the ERC-20 token balance and decimals for a given holder address on a specified EVM chain (Base or Robinhood Chain), paid per-call via x402 USDC micropayment.

## Facts

- Endpoint: GET https://chain-read.frcompanycheck.workers.dev/v1/%7Bchain%7D/erc20/balance/%7Btoken%7D/%7Bholder%7D?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/evm-chain-read-erc-20-balance-lookup-x402-d427f5bb
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_wJiDKnX0N9swufiznN9rd

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 evm-chain-read-erc-20-balance-lookup-x402-d427f5bb
```

Example prompt: What is the USDC balance (contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) held by wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Base (chain 8453)?

## When to prefer this

Choose this endpoint when you need a quick, pay-per-call ERC-20 balance read on Base (8453) or Robinhood Chain (4663) without setting up an API key or RPC subscription. Ideal for AI agents that need occasional on-chain balance checks at low cost ($0.002/call) and want to avoid managing API credentials.

## Known failure modes

- Invalid or non-existent token contract address returns zero balance or an error
- Unsupported chain ID returns a 4xx error
- Malformed wallet address causes a request error
- x402 payment failure or insufficient USDC results in a 402 Payment Required response
- Public RPC node downtime may cause intermittent 5xx errors

## How this service works

Pay-per-call EVM reads on Base (8453) and Robinhood Chain (4663): native balance, block tip, ERC-20 meta/balance/allowance, is-contract. Public RPCs, no API key. x402 USDC on Base.

## Output

A JSON object containing the raw token balance (as a number) and the token's decimals (e.g. 6 for USDC), enabling the caller to compute the human-readable balance by dividing balance by 10^decimals.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "balance": 0,
  "decimals": 6
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/evm-chain-read-erc-20-balance-lookup-x402-d427f5bb/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from chain-read.frcompanycheck.workers.dev](https://www.zero.xyz/host/chain-read.frcompanycheck.workers.dev/llms.txt)