# ONE Engine Array Difference

> ONE Engine Array Difference is a paid API for AI agents from one-search.one-engine.workers.dev, paid per call via x402, $0.004/call, status unknown (last checked 2026-10-02).

Computes the difference between two arrays, returning elements present in the first array but not in the second.

## Facts

- Endpoint: POST https://one-search.one-engine.workers.dev/v3/array/difference/t6?utm_source=zero.xyz
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/one-engine-array-difference-d66f9fae
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_hV7ktcT6Xs-FEPwQQN5GA

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 one-engine-array-difference-d66f9fae -d '<json body>'
```

Example prompt: I have two lists of product IDs — take the first list [101, 102, 103, 104] and remove any IDs that appear in the second list [102, 104], then return what's left.

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call array difference computation without spinning up your own infrastructure. It is ideal for autonomous agents operating on Base/x402 that need fast set subtraction on arrays up to 1000 items, and where a serverless utility call is cheaper than implementing custom logic. Prefer alternatives if you need difference on arrays larger than 1000 items, need symmetric difference, or require union/intersection operations instead.

## Known failure modes

- Input 'values' array exceeds 1000-item limit — request rejected
- Missing required 'values' field — validation error returned
- Malformed JSON body — parse error
- Payment not included or insufficient — 402 Payment Required response
- Non-array value passed for 'values' or 'other' — schema validation failure

## How this service works

Low-cost pay-per-call utility APIs for autonomous agents using x402 on Base.

## Output

Returns a JSON object containing the array of elements present in the 'values' input array but absent from the 'other' comparison array, effectively the set difference (A minus B).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "values"
 ],
 "properties": {
  "size": {
   "type": "integer"
  },
  "other": {
   "type": "array",
   "description": "Optional comparison array"
  },
  "offset": {
   "type": "integer"
  },
  "values": {
   "type": "array",
   "description": "JSON array with at most 1000 items"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "additionalProperties": true
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/one-engine-array-difference-d66f9fae/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from one-search.one-engine.workers.dev](https://www.zero.xyz/host/one-search.one-engine.workers.dev/llms.txt)