# x402 AI Gateway – Currency Conversion Endpoint

> x402 AI Gateway – Currency Conversion Endpoint is a paid API for AI agents from api.fastapi.online, paid per call via x402, $0.0002/call, status unknown (last checked 2026-10-13).

Converts a specified amount from one currency to another, gated behind an x402 USDC micropayment on Base before executing.

## Facts

- Endpoint: POST https://api.fastapi.online/f/fx/aoa/try?utm_source=zero.xyz
- Price: $0.0002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-ai-gateway-currency-conversion-endpoint-af869fd3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_QYf6tGLbg4dzKCF5_G6Wi

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-conversion-endpoint-af869fd3 -d '<json body>'
```

Example prompt: Can you convert 250 USD to EUR for me using the x402 micropayment-gated currency converter? Just send the 0.0002 USDC payment and give me the result.

## When to prefer this

Choose this endpoint when you need a pay-per-use, self-hosted currency conversion with x402 micropayment support on Base (USDC), especially in agent workflows where you want to avoid subscription-based FX APIs and prefer fractional per-call billing at $0.0002 per request. It is well-suited for low-frequency, on-demand currency lookups embedded in autonomous agent pipelines.

## Known failure modes

- Payment not provided or insufficient USDC — returns HTTP 402 Payment Required
- Invalid or unsupported currency codes — may return an error or empty result
- Amount parameter missing — defaults to 1 or may error
- Network/gateway unavailability — connection timeout or 5xx error
- Stale or unavailable exchange rate data — may return outdated or null values

## How this service works

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

## Output

A JSON object containing the converted currency value for the specified amount, likely including the resulting amount and possibly the exchange rate applied. The exact schema is unspecified beyond a generic object response.

## 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-conversion-endpoint-af869fd3/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)