# SignalDesk AI Factorial Calculator

> SignalDesk AI Factorial Calculator is a paid API for AI agents from x402-agent.kariguetoazul.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-13).

Computes the exact factorial of a non-negative integer n (0 ≤ n ≤ 300) and returns the result as a string

## Facts

- Endpoint: POST https://x402-agent.kariguetoazul.workers.dev/api/math/factorial?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signaldesk-ai-factorial-calculator-d2451003
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_RxPHmeqd83mhoTcKEkQqu

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 signaldesk-ai-factorial-calculator-d2451003 -d '<json body>'
```

Example prompt: What is the factorial of 150? Give me the exact full integer value.

## When to prefer this

Use this endpoint when you need the exact integer value of a factorial (no floating-point approximation) for values of n up to 300. It is preferable to local computation when the agent environment lacks arbitrary-precision math libraries, or when a verifiable, paid API result is required for audit or evidence purposes. Avoid if n > 300 or if approximate scientific notation is acceptable.

## Known failure modes

- Input n exceeds maximum of 300 — returns validation error
- Input n is negative — rejected by schema validation
- Non-integer input — schema validation failure
- Payment of 0.001 USDC not fulfilled — x402 payment required error before computation
- Network timeout on Cloudflare Worker edge node

## How this service works

Evidence-backed autonomous AI jobs and paid data tools. Queue/D1/cron run outside the chat; free quotas and bounded execution apply.

## Output

A JSON object containing a 'factorial' field with the exact result of n! as a string (e.g. {"factorial": "3628800"} for n=10). Large factorials (e.g. n=300) return very long numeric strings with full precision.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "n": {
   "type": "integer",
   "maximum": 300,
   "minimum": 0,
   "description": "n."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "factorial": "3628800"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signaldesk-ai-factorial-calculator-d2451003/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-agent.kariguetoazul.workers.dev](https://www.zero.xyz/host/x402-agent.kariguetoazul.workers.dev/llms.txt)