# ONE Engine Stable Sort Array

> ONE Engine Stable Sort Array is a paid API for AI agents from one-search.one-engine.workers.dev, paid per call via x402, $0.0015/call, status unknown (last checked 2026-10-02).

Sorts a JSON array of up to 1000 items using a stable sort algorithm, with optional comparison array support.

## Facts

- Endpoint: POST https://one-search.one-engine.workers.dev/v3/array/stable-sort/t4?utm_source=zero.xyz
- Price: $0.0015/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-stable-sort-array-b4b88f11
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_S9CtZdxmvoPovTxIWWu-b

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-stable-sort-array-b4b88f11 -d '<json body>'
```

Example prompt: Sort this array of values [42, 7, 19, 3, 55, 7, 1] using a stable sort so equal elements keep their original relative order.

## When to prefer this

Choose this endpoint when you need a guaranteed stable sort (equal elements preserve their original order) on a JSON array of up to 1000 items without spinning up your own compute. Ideal for autonomous agents needing lightweight, pay-per-call data ordering without managing server infrastructure. Prefer over client-side sorting when the agent runtime lacks reliable sort primitives or when auditability of the sort operation is needed.

## Known failure modes

- Array exceeds 1000 items — request rejected
- Invalid or non-array 'values' field — validation error
- Malformed JSON body — parse error
- Payment not provided or insufficient — 402 Payment Required
- Comparison array type mismatch — sort may error or return unexpected results

## 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 stably-sorted version of the input array, preserving the relative order of equal elements as they appeared in the original input.

## 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-stable-sort-array-b4b88f11/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)