# ONE Engine Percent Change (t1)

> ONE Engine Percent Change (t1) is a paid API for AI agents from one-search.one-engine.workers.dev, paid per call via x402, $0.0005/call, status unknown (last checked 2026-10-02).

Computes percent change between consecutive numeric values in a provided array, with optional scaling and bounding parameters.

## Facts

- Endpoint: POST https://one-search.one-engine.workers.dev/v3/numeric/percent-change/t1?utm_source=zero.xyz
- Price: $0.0005/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-percent-change-t1-ed1d3f7b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MY6CRNh0e54CwFlV7AcSz

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-percent-change-t1-ed1d3f7b -d '<json body>'
```

Example prompt: Calculate the percent change between each consecutive value in this list: [100, 115, 108, 132, 120], rounded to 2 decimal digits.

## When to prefer this

Choose this endpoint when you need a lightweight, low-cost ($0.0005 USDC) pay-per-call computation of sequential percent changes on a numeric array without standing up your own compute infrastructure. Ideal for AI agents running on Base that need on-demand statistical transformation without managing servers or libraries.

## Known failure modes

- Input array exceeds 1000 elements — request rejected
- Non-finite numbers (NaN, Infinity) in values array cause computation errors
- Missing required 'values' field returns a validation error
- Payment not included or invalid x402 payment header causes 402 response
- Division by zero when a value is 0 and percent change is undefined

## How this service works

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

## Output

Returns a JSON object containing computed percent change values for each consecutive pair in the input array, optionally scaled by a factor, offset, clamped to min/max bounds, sized to a specific output length, and rounded to a specified number of decimal digits.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "values"
 ],
 "properties": {
  "max": {
   "type": "number"
  },
  "min": {
   "type": "number"
  },
  "size": {
   "type": "integer"
  },
  "digits": {
   "type": "integer"
  },
  "factor": {
   "type": "number"
  },
  "offset": {
   "type": "number"
  },
  "values": {
   "type": "array",
   "description": "Finite numbers, maximum 1000"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "additionalProperties": true
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/one-engine-percent-change-t1-ed1d3f7b/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)