# PennyRail Number Stats – Mean & Median

> PennyRail Number Stats – Mean & Median is a paid API for AI agents from pennyrail.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Computes descriptive statistics (mean and median) for a provided array of numbers

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/p/nano/number.stats--mean-median
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pennyrail-number-stats-mean-median-153cbf4d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_tdApZufhdAvKEjyvx718W

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 pennyrail-number-stats-mean-median-153cbf4d -d '<json body>'
```

Example prompt: Can you calculate the mean and median for this list of numbers: [12, 45, 7, 23, 89, 34, 56, 11, 67, 30]?

## When to prefer this

Choose this endpoint when you need a quick, pay-per-use computation of mean and median for a numeric array without standing up your own statistics infrastructure. Ideal for lightweight agent workflows where you want to outsource basic statistical computation at $0.001 per call rather than embedding a math library. Best suited for one-off or low-frequency statistical lookups in agentic pipelines.

## Known failure modes

- Empty input array returns an error or undefined result
- Non-numeric values in the array may cause computation failure or be ignored
- Missing required 'input' field returns a validation error
- Payment failure (x402) blocks the request before computation
- Very large arrays may time out depending on serverless execution limits

## How this service works

Machine-readable settlement service

## Output

Returns a JSON object containing computed statistical values including the mean (arithmetic average) and median (middle value) of the input numeric array. The response may also include additional descriptive statistics.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "array"
  }
 }
}
```

## Response schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pennyrail-number-stats-mean-median-153cbf4d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from pennyrail.vercel.app](https://www.zero.xyz/host/pennyrail.vercel.app/llms.txt)