# Array Intersection (T9)

> Array Intersection (T9) is a paid API for AI agents from one-search.one-engine.workers.dev, paid per call via x402, $0.018/call, status unknown (last checked 2026-10-02).

Computes the intersection of two arrays, returning elements common to both input arrays.

## Facts

- Endpoint: POST https://one-search.one-engine.workers.dev/v3/array/intersection/t9?utm_source=zero.xyz
- Price: $0.018/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/array-intersection-t9-3c3d404f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_j3tjIwyfn4l02L4hb571p

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 array-intersection-t9-3c3d404f -d '<json body>'
```

Example prompt: Find all the common elements between these two arrays: [1, 2, 3, 4, 5] and [3, 4, 5, 6, 7] — return up to 100 results.

## When to prefer this

Choose this endpoint when you need a fast, pay-per-call array intersection with no setup or infrastructure required, especially within agent pipelines using x402/Base micropayments. Ideal for lightweight set operations on arrays up to 1000 items where spinning up custom code is overkill.

## Known failure modes

- Missing required `values` field returns validation error
- Array exceeds 1000-item limit causes rejection
- Malformed JSON array in input causes parse error
- Payment failure or insufficient USDC balance returns 402
- Network timeout on large array processing

## 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 appear in both the primary `values` array and the `other` comparison array, representing the set intersection. May support pagination via `size` and `offset` parameters to limit result size.

## 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/array-intersection-t9-3c3d404f/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)