# x402 AI Gateway — Currency Amount Converter

> x402 AI Gateway — Currency Amount Converter is a paid API for AI agents from api.fastapi.online, paid per call via x402, $0.0002/call, status unknown (last checked 2026-10-12).

Converts a specified amount of a source currency via a self-hosted AI gateway endpoint gated by an x402 USDC micropayment on Base.

## Facts

- Endpoint: POST https://api.fastapi.online/f/fx/ang/kmf?utm_source=zero.xyz
- Price: $0.0002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-ai-gateway-currency-amount-converter-4764dccf
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ezj0PT1fH3fJj7bIN00Fu

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-ai-gateway-currency-amount-converter-4764dccf -d '<json body>'
```

Example prompt: Convert 50 units of my source currency using the x402 micropayment gateway — I'm okay with a $0.0002 USDC charge on Base per call.

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call currency conversion via a self-hosted AI gateway that uses the x402 micropayment protocol on Base (USDC). It is ideal for agents with crypto wallets on Base that want to avoid subscription fees and instead pay fractions of a cent per conversion call.

## Known failure modes

- Payment not authorized or insufficient USDC balance on Base — gateway returns 402 Payment Required
- Invalid or missing 'amount' field — API may return 400 or default to 1
- Gateway unavailable or self-hosted server down — 5xx error
- x402 facilitator or payment channel failure — transaction not processed, request blocked
- Unexpected empty or malformed JSON response object

## How this service works

Self-hosted AI API gateway. Expensive endpoints require an x402 micropayment (USDC on Base) before executing.

## Output

Returns a JSON object containing the result of the currency conversion computation. Exact fields are unspecified in the schema but typically include the converted amount or rate-related data.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "amount": {
   "type": "number",
   "description": "Amount of the source currency to convert (default 1)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-ai-gateway-currency-amount-converter-4764dccf/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.fastapi.online](https://www.zero.xyz/host/api.fastapi.online/llms.txt)