# 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, gated behind an x402 USDC micropayment on Base.

## Facts

- Endpoint: POST https://api.fastapi.online/f/fx/ang/omr?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-c4f13193
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UG1IhO1lXOA7H5GAhmQKA

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-c4f13193 -d '<json body>'
```

Example prompt: Convert 250 units of source currency using the x402 AI Gateway fx endpoint — I need the converted result back.

## When to prefer this

Choose this endpoint when you need a low-cost, per-call currency amount conversion accessible via the x402 micropayment protocol (USDC on Base), particularly in autonomous agent pipelines that already handle x402 payment flows. Prefer this over public free FX APIs when your stack is already integrated with the x402 payment rail and you want a unified self-hosted gateway experience.

## Known failure modes

- 402 Payment Required — x402 micropayment not attached or insufficient USDC balance on Base
- Invalid or missing 'amount' field — must be a numeric value
- Unsupported currency pair — source or target currency not recognized
- Network or gateway timeout from the self-hosted inference server
- Empty or malformed response object if upstream FX data is unavailable

## 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, including the converted amount or equivalent value for the input currency quantity provided.

## 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-c4f13193/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)