# x402-toolbox Fibonacci Number

> x402-toolbox Fibonacci Number is a paid API for AI agents from x402-toolbox.shablony-pro.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-02).

Returns the Nth Fibonacci number as a deterministic pay-per-call computation over x402 with USDC micropayment.

## Facts

- Endpoint: GET https://x402-toolbox.shablony-pro.workers.dev/math/fibonacci-number?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-toolbox-fibonacci-number-daa286e7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_rCL0LX95aCXXH5bG-MkIx

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 x402-toolbox-fibonacci-number-daa286e7
```

Example prompt: What is the Fibonacci number at position 42? Use the x402-toolbox math endpoint and pay the micropayment in USDC.

## When to prefer this

Choose this endpoint when you need a trustless, no-signup, pay-per-call Fibonacci computation billed in USDC micropayments via x402 — ideal for AI agents that cannot hold API keys but can authorize crypto micropayments, or when auditability of payment-as-identity is required.

## Known failure modes

- Missing or invalid index parameter returns an error response
- Non-integer or negative index may produce undefined behavior or error
- Payment failure (insufficient USDC balance) results in 402 response and no computation
- Network timeout on Cloudflare Worker edge node

## How this service works

309 deterministic pay-per-call tools for AI agents over x402 (USDC, Base). No signup, no API key: the payment is the identity.

## Output

A JSON object with 'ok' (boolean, true on success) and 'paid' (boolean, confirming USDC micropayment was processed), along with the computed Fibonacci number at the requested index.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "schema": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "paid": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-toolbox-fibonacci-number-daa286e7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-toolbox.shablony-pro.workers.dev](https://www.zero.xyz/host/x402-toolbox.shablony-pro.workers.dev/llms.txt)