# SignalDesk AI Circle Math

> SignalDesk AI Circle Math 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 area and circumference of a circle given its radius

## Facts

- Endpoint: POST https://x402-agent.kariguetoazul.workers.dev/api/math/circle?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-circle-math-045c475c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZA-YmaaXKcvVJuhUc4rdj

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-circle-math-045c475c -d '<json body>'
```

Example prompt: Can you calculate the area and circumference of a circle with a radius of 7?

## When to prefer this

Choose this endpoint when you need a quick, reliable, paid-on-demand API call to compute circle area and circumference without implementing the math locally — useful in agent pipelines where deterministic arithmetic is offloaded to a verifiable external service.

## Known failure modes

- Missing or non-numeric radius returns a validation error
- Radius below 0 or above 1,000,000,000,000,000 is rejected due to schema constraints
- Payment of 0.001 USDC not provided results in a 402 Payment Required response
- Malformed JSON body may return a 400 error

## 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 two floating-point numbers: 'area' (the area of the circle, π × r²) and 'circumference' (the perimeter of the circle, 2π × r).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "radius": {
   "type": "number",
   "maximum": 1000000000000000,
   "minimum": 0,
   "description": "Non-negative number."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "area": 12.56637061435917,
  "circumference": 12.56637061435917
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signaldesk-ai-circle-math-045c475c/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)