# Base Reads – USDC Balance Lookup

> Base Reads – USDC Balance Lookup is a paid API for AI agents from base-reads-api.rafliyaputra.deno.net, paid per call via x402, $0.001/call, status unknown (last checked 2026-11-01).

Returns the USDC (and ETH) balance of a given Base network address at the latest block, for $0.001 USDC per call via x402.

## Facts

- Endpoint: GET https://base-reads-api.rafliyaputra.deno.net/base/usdc-balance?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-reads-usdc-balance-lookup-5f2bfb9c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_4xSmX1dbv8qEF1bqBYH_z

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 base-reads-usdc-balance-lookup-5f2bfb9c
```

Example prompt: What's the current USDC balance for the Base address 0x4200000000000000000000000000000000000016?

## When to prefer this

Use this endpoint when you need a cheap ($0.001 USDC), deterministic, pay-per-call read of a wallet's USDC balance on the Base L2 network without setting up your own RPC node or indexer. Ideal for agents that need occasional on-demand balance checks rather than continuous streaming. Prefer over general Ethereum RPC providers when you specifically need Base network data with x402 micropayment billing.

## Known failure modes

- Invalid address format (not matching ^0x[0-9a-fA-F]{40}$) returns a validation error
- Missing address query parameter returns a 400-level error
- Payment not provided or invalid x402 payment header returns 402 Payment Required
- RPC/node unavailability may cause transient 5xx errors
- Rate limiting if payment processing fails on the facilitator side

## How this service works

Pay-per-call read API for Base over x402 v2. Deterministic data, no advice.

## Output

A JSON object containing the wallet's USDC balance in human-readable form and raw units (usdc and usdc_raw), ETH balance in ETH and wei (eth and eth_wei), the block number at which the read was taken (block), the chain name (base), and the queried address. Example: {eth: 0.25, usdc: 12.5, block: 36000000, chain: 'base', address: '0x...', eth_wei: '250000000000000000', usdc_raw: '12500000'}.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "address": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$",
       "description": "Base address to read (0x + 40 hex chars)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "eth": 0.25,
  "usdc": 12.5,
  "block": 36000000,
  "chain": "base",
  "address": "0x4200000000000000000000000000000000000016",
  "eth_wei": "250000000000000000",
  "usdc_raw": "12500000"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-reads-usdc-balance-lookup-5f2bfb9c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from base-reads-api.rafliyaputra.deno.net](https://www.zero.xyz/host/base-reads-api.rafliyaputra.deno.net/llms.txt)