# PennyRail Numeric Summary Statistics

> PennyRail Numeric Summary Statistics is a paid API for AI agents from pennyrail.vercel.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-13).

Computes descriptive numeric summary statistics (count, mean, median, min, max, std dev, etc.) for an array of numbers

## Facts

- Endpoint: POST https://pennyrail.vercel.app/api/p/nano/number.stats--numeric-summary
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pennyrail-numeric-summary-statistics-0fd77895
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ipYiu43AECS0ZVvIoJQYf

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-numeric-summary-statistics-0fd77895 -d '<json body>'
```

Example prompt: Can you give me a numeric summary — mean, median, min, max, standard deviation — for this list of values: [4.2, 7.8, 3.1, 9.5, 6.0, 2.3, 8.7]?

## When to prefer this

Choose this endpoint when you need quick, pay-per-call descriptive statistics on a numeric array without setting up a data science environment. It is ideal for lightweight agent workflows that occasionally need to summarize a column of numbers, sensor readings, or financial figures without the overhead of a full analytics stack.

## Known failure modes

- Empty or missing input array returns validation error
- Non-numeric values in the array may cause computation errors or be silently skipped
- Payment failure (402) if USDC balance insufficient
- Malformed request body (missing 'input' field) returns 400
- Very large arrays may time out or exceed memory limits on serverless infrastructure

## How this service works

Machine-readable settlement service

## Output

A JSON object containing descriptive numeric statistics computed over the input array, typically including count, mean, median, min, max, standard deviation, and possibly additional percentile or distribution metrics.

## 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-numeric-summary-statistics-0fd77895/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)