# ONE Engine Array Tail — Last 3 Items (Tier 2)

> ONE Engine Array Tail — Last 3 Items (Tier 2) is a paid API for AI agents from one-search.one-engine.workers.dev, paid per call via x402, $0.0006/call, status unknown (last checked 2026-10-12).

Returns the last 3 elements of a JSON array, with Tier 2 richer diagnostic information included in the response.

## Facts

- Endpoint: POST https://one-search.one-engine.workers.dev/v6/array-tail/items-3/t2?utm_source=zero.xyz
- Price: $0.0006/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/one-engine-array-tail-last-3-items-tier-2-d1301a15
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dtD-uUotDa7bf-evO5szX

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-tail-last-3-items-tier-2-d1301a15 -d '<json body>'
```

Example prompt: I have a JSON array and I need just the last 3 items from it — can you slice it and give me back those final 3 elements along with any diagnostic info?

## When to prefer this

Choose this endpoint when you need a cheap, deterministic, pay-per-call utility to extract the tail (last 3 elements) of a JSON array and you also want richer diagnostic output (Tier 2) compared to the base tier. Ideal for autonomous agents that process ordered lists and need just the most recent or final entries without custom code. Prefer over Tier 1 when diagnostics matter for debugging or logging.

## Known failure modes

- Input is not a valid JSON array — returns a 400 error
- Array has fewer than 3 elements — may return all available elements or an error
- Payment not provided or invalid x402 payment header — returns 402 Payment Required
- Malformed request body — returns 400 or 422 error
- Network timeout on the Workers edge — returns 503 or 504

## How this service works

Return last 3 array items. Tier 2/10 adds richer diagnostics.

## Output

Returns a JSON object containing an array of the last 3 elements from the input array, plus Tier 2 richer diagnostic metadata such as input length, operation performed, tier info, and processing details.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/one-engine-array-tail-last-3-items-tier-2-d1301a15/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)