# x402-toolbox NFT Balance Checker

> x402-toolbox NFT Balance Checker is a paid API for AI agents from x402-toolbox.shablony-pro.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-02).

Returns the NFT (non-fungible token) balance for a given blockchain address on a specified chain, paid per-call via x402/USDC with no API key required.

## Facts

- Endpoint: GET https://x402-toolbox.shablony-pro.workers.dev/chain/nft-balance?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-toolbox-nft-balance-checker-432258ab
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ER8Jg5DkTuyakLbtkHFgv

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-toolbox-nft-balance-checker-432258ab
```

Example prompt: Check the NFT balance on Base chain for wallet address 0xAbCd1234... — pay the micro-fee automatically with USDC, no API key needed.

## When to prefer this

Choose this endpoint when you need a frictionless, no-signup NFT balance lookup payable per-call in USDC over x402, especially in autonomous agent workflows where managing API keys is undesirable. It is ideal for Base chain queries and micro-payment-native pipelines.

## Known failure modes

- Invalid or malformed wallet address returns an error response
- Unsupported chain schema returns a bad request
- Payment failure (insufficient USDC or wallet issue) prevents the call from executing
- Rate limits or Cloudflare Worker timeouts on high-volume requests
- Missing required schema parameter results in an ambiguous or empty response

## How this service works

309 deterministic pay-per-call tools for AI agents over x402 (USDC, Base). No signup, no API key: the payment is the identity.

## Output

A JSON object with an 'ok' boolean indicating success, a 'paid' boolean confirming the x402 micro-payment was accepted, and the NFT balance data for the queried address on the specified chain.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "paid": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-toolbox-nft-balance-checker-432258ab/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-toolbox.shablony-pro.workers.dev](https://www.zero.xyz/host/x402-toolbox.shablony-pro.workers.dev/llms.txt)