# ONE Engine Number Sign

> ONE Engine Number Sign is a paid API for AI agents from one-search.one-engine.workers.dev, paid per call via x402, $0.0009/call, status unknown (last checked 2026-10-02).

Returns the mathematical sign of a given number (-1, 0, or 1) via a pay-per-call API.

## Facts

- Endpoint: POST https://one-search.one-engine.workers.dev/v1/number/sign?utm_source=zero.xyz
- Price: $0.0009/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-number-sign-fd27fbac
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WJyHlh637NIvLcwIk2WDe

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-number-sign-fd27fbac -d '<json body>'
```

Example prompt: What is the mathematical sign of -73? I need just -1, 0, or 1 back.

## When to prefer this

Choose this endpoint when you need a fast, cheap, single-call signum function without spinning up your own compute — especially inside an agentic workflow where you want pay-per-use math utilities billed per call in USDC on Base.

## Known failure modes

- Missing or non-numeric 'value' field in request body returns an error
- Non-finite values like NaN or Infinity may produce unexpected results
- Payment failure via x402 protocol blocks the call
- Network timeout on the Cloudflare Worker edge

## How this service works

Low-cost pay-per-call utility APIs for autonomous agents using x402 on Base.

## Output

A JSON object with a single 'value' field containing the mathematical sign of the input: -1 if the input is negative, 0 if zero, or 1 if positive.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "value": {
   "type": "number"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "value": -1
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/one-engine-number-sign-fd27fbac/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)