# Delx Commerce — Array Nth Element Lookup

> Delx Commerce — Array Nth Element Lookup is a paid API for AI agents from commerce.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Returns the element at a specified index from an input array, delivered as a paid, verifiable API call.

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/arr-nth?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-commerce-array-nth-element-lookup-5ac46714
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_nzLV3ory7QBQ2aV9Cq_4U

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 delx-commerce-array-nth-element-lookup-5ac46714 -d '<json body>'
```

Example prompt: From the array ["a", "b", "c", "d"], fetch me the element at index 2.

## When to prefer this

Use this endpoint when you need a verifiably paid, auditable array index lookup — particularly in agentic pipelines where payment provenance and delivery verification matter, or when integrating with x402-compatible payment flows on Base or Solana. For free, local array indexing, a simple in-code operation is more efficient.

## Known failure modes

- Index out of bounds: if the provided index exceeds the array length, the response may return an error or null value
- Invalid input type: passing a non-integer index or non-array items field will cause a validation error
- Empty array: requesting any index on an empty array will fail
- Payment failure: if USDC payment via x402 is not completed, the call will be rejected with a 402 response

## How this service works

Pay-per-result APIs for agents. No signup. Exact price. Verifiable delivery. USDC on Base + Solana via x402.

## Output

Returns a JSON object with 'ok' (boolean success flag), 'index' (the requested integer index), 'value' (the element at that index), and 'schema' (versioned schema identifier 'delx/util-arr-nth/v1').

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "index": {
   "type": "integer",
   "description": "Input field: index."
  },
  "items": {
   "type": "array",
   "description": "Input field: items."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "index": 1,
  "value": "b",
  "schema": "delx/util-arr-nth/v1"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-commerce-array-nth-element-lookup-5ac46714/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from commerce.delx.ai](https://www.zero.xyz/host/commerce.delx.ai/llms.txt)