# Postandshare ERC-20 Token Balance Lookup

> Postandshare ERC-20 Token Balance Lookup is a paid API for AI agents from api.postandshare.net, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-28).

Returns ERC-20 token balance for a given wallet address and contract on Base, Ethereum, Arbitrum, or Polygon

## Facts

- Endpoint: GET https://api.postandshare.net/v1/chain/token?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-28
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/postandshare-erc-20-token-balance-lookup-e5054c09
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WrhOis5Fy_1loMfUBifnW

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 postandshare-erc-20-token-balance-lookup-e5054c09
```

Example prompt: What's the USDC balance (contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) held by wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Ethereum?

## When to prefer this

Choose this endpoint when you need a pay-per-call, no-infrastructure ERC-20 token balance read across Base, Ethereum, Arbitrum, or Polygon without managing your own RPC node. Ideal for AI agents that need occasional on-chain reads without committing to a full blockchain data provider subscription. At $0.001 USDC per call via x402, it suits low-frequency or on-demand balance checks in agentic workflows.

## Known failure modes

- Invalid or malformed 0x-prefixed address returns an error
- Unsupported network value returns a validation error
- Token contract address that is not a valid ERC-20 contract may return zero or an error
- Network congestion or RPC issues may cause timeouts
- Missing required token or holder parameter returns 400-level error

## How this service works

x402 pay-per-call data endpoints for AI agents: multi-chain reads (Base, Ethereum, Arbitrum, Polygon) and Nigerian reference data. Format/reference validation only — no personal data, no identity-database lookup.

## Output

Returns the on-chain ERC-20 token balance for the specified wallet address and token contract on the requested network. Typically includes the raw balance amount and possibly formatted decimals.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "token": {
   "type": "string",
   "description": "0x-prefixed ERC-20 contract address"
  },
  "holder": {
   "type": "string",
   "description": "0x-prefixed wallet address"
  },
  "network": {
   "enum": [
    "base",
    "ethereum",
    "arbitrum",
    "polygon"
   ],
   "type": "string",
   "description": "Chain to read (default base)"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/postandshare-erc-20-token-balance-lookup-e5054c09/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.postandshare.net](https://www.zero.xyz/host/api.postandshare.net/llms.txt)