# ONE Engine Array Flatten

> ONE Engine Array Flatten 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).

Flattens a nested JSON array into a single-level array, with optional slicing and comparison array support.

## Facts

- Endpoint: POST https://one-search.one-engine.workers.dev/v3/array/flatten/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-flatten-75687f99
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_W7CLl0BvTULjds6lu4pji

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-flatten-75687f99 -d '<json body>'
```

Example prompt: Flatten this nested JSON array for me — it has up to 50 items and looks like [[1,2],[3,[4,5]],6] — I just need all the values in one flat list, starting from offset 0.

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call array flattening operation without deploying your own transformation logic. Ideal for autonomous agents that need to normalize nested JSON arrays on demand at low cost ($0.01 USDC per call via x402 on Base). Best suited for arrays up to 1000 items. Prefer this over writing custom code when you need a quick, reliable serverless transformation in an agent workflow.

## Known failure modes

- Input array exceeds 1000-item limit — returns an error or truncated result
- Malformed JSON array in 'values' field — returns a parsing or validation error
- Payment failure via x402 on Base — request not processed, 402 response returned
- Empty 'values' array — may return an empty result or minimal response
- Invalid types for 'offset' or 'size' — may return a validation error

## 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 flattened (single-level) version of the input nested array, with optional offset and size slicing applied. The response schema is open (additionalProperties: true), so the flattened result and any metadata are included in the response object.

## 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-flatten-75687f99/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)