# Delx Commerce — Is-Subset Array Validator

> Delx Commerce — Is-Subset Array Validator 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).

Checks whether array A is a subset of array B, returning a boolean result with element counts for both arrays.

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/is-subset?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-is-subset-array-validator-4bd3fc05
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_H6yPx1Ut2Xlii0bNvUSHU

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-is-subset-array-validator-4bd3fc05 -d '<json body>'
```

Example prompt: Can you check if ["apple", "banana"] is a subset of ["apple", "banana", "cherry", "date"]?

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call subset check with no signup overhead, especially in agent workflows that require verifiable, micropayment-gated computation. Prefer it over implementing custom set logic when you want a stateless, auditable result with guaranteed delivery confirmation via USDC on Base or Solana.

## Known failure modes

- Missing or malformed 'a' or 'b' fields returns an error
- Non-array values for 'a' or 'b' may cause a validation error
- Payment failure via x402 protocol results in a 402 response and no result
- Empty array A may return subset=true (vacuous truth), which can be unexpected

## 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 a 'subset' boolean indicating whether array A is entirely contained in array B, along with 'a_count' (number of elements in A) and 'b_count' (number of elements in B), and a schema identifier string.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "a": {
   "type": "array",
   "description": "Input field: a."
  },
  "b": {
   "type": "array",
   "description": "Input field: b."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "schema": "delx/util-is-subset/v1",
  "subset": true,
  "a_count": 2,
  "b_count": 3
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-commerce-is-subset-array-validator-4bd3fc05/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)