# SignalDesk AI Percent Change Calculator

> SignalDesk AI Percent Change 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 percentage change between two numeric values (before and after)

## Facts

- Endpoint: POST https://x402-agent.kariguetoazul.workers.dev/api/math/percent-change?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-percent-change-calculator-c149ceae
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VkPktUc75NcA2MPcpoNma

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-percent-change-calculator-c149ceae -d '<json body>'
```

Example prompt: What's the percentage change from 250 to 300? I need the exact percent increase.

## When to prefer this

Use this endpoint when you need a reliable, hosted API call for percent change computation rather than doing inline arithmetic — especially in agentic pipelines where you want auditable, paid computation steps, or when integrating with x402 payment flows on Cloudflare Workers infrastructure.

## Known failure modes

- Division by zero if 'before' is 0 — result undefined or error returned
- Values outside the allowed range (-1,000,000,000,000,000 to 1,000,000,000,000,000) will be rejected
- Non-numeric or missing 'before'/'after' fields may cause a 400/validation error
- Payment failure (x402) if USDC not provided, returning 402 Payment Required

## 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 single field 'percent_change' representing the calculated percentage change from the 'before' value to the 'after' value as a number (e.g. {"percent_change": 20}).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "after": {
   "type": "number",
   "maximum": 1000000000000000,
   "minimum": -1000000000000000,
   "description": "Finite number."
  },
  "before": {
   "type": "number",
   "maximum": 1000000000000000,
   "minimum": -1000000000000000,
   "description": "Finite number."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "percent_change": 20
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signaldesk-ai-percent-change-calculator-c149ceae/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)