# 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, $0.01/call, status unknown (last checked 2026-10-02).

Computes the difference between two arrays, returning elements present in the input array but not in the comparison array.

## Facts

- Endpoint: POST https://one-search.one-engine.workers.dev/v3/array/difference/t8?utm_source=zero.xyz
- Price: $0.01/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-379d89dd
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_iti_bY_6HYwhO0f_tKnyB

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-379d89dd -d '<json body>'
```

Example prompt: I have two lists of user IDs — [101, 202, 303, 404] and [202, 404] — can you compute the difference and give me back only the IDs from the first list that don't appear in the second?

## When to prefer this

Use this endpoint when you need a quick, cheap ($0.01 USDC), pay-per-call array difference computation without standing up your own infrastructure. Ideal for autonomous agents that occasionally need set subtraction on moderate-sized arrays (up to 1000 items) as part of a larger workflow, without needing a full database or compute environment.

## Known failure modes

- Input array exceeds 1000 items — rejected with validation error
- Missing required `values` field — returns 400-level error
- Payment not included or insufficient — returns HTTP 402 requiring x402 payment on Base
- Malformed JSON body — parse error response
- Network timeout on Cloudflare Worker edge

## 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 that are present in the `values` input array but absent from the `other` comparison array, effectively the set difference A minus B. Supports optional pagination via `size` and `offset` parameters.

## 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-379d89dd/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)