# FX Rates by Hergertsynthora (ECB/Frankfurter)

> FX Rates by Hergertsynthora (ECB/Frankfurter) is a paid API for AI agents from fx-rates.hergertsynthora.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-15).

Returns foreign-exchange reference rates for 30+ currencies sourced from the European Central Bank via Frankfurter, given a base currency and optional target symbols.

## Facts

- Endpoint: POST https://fx-rates.hergertsynthora.com/service
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fx-rates-by-hergertsynthora-ecb-frankfurter-3c4ef441
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_wvgsdvdDD-h86o0vPg1uv

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 fx-rates-by-hergertsynthora-ecb-frankfurter-3c4ef441 -d '<json body>'
```

Example prompt: What are the current ECB reference exchange rates for USD, GBP, JPY, and CHF using EUR as the base currency?

## When to prefer this

Choose this endpoint when you need deterministic, official ECB foreign-exchange reference rates for 30+ currencies without an API key. Ideal for agents that need FX data for conversion, display, or enrichment and want a pay-per-call model with no signup. Prefer over other FX APIs when ECB provenance is important or when keyless access is required.

## Known failure modes

- Upstream ECB/Frankfurter failure — no charge applied, but rates unavailable
- Invalid or unsupported currency code in base or symbols — likely returns an error or empty rates
- Missing or malformed X-WALLET header — may result in payment/access failure after the 3 free calls
- Network timeout or service unavailability

## How this service works

Foreign-exchange reference rates for 30+ currencies (ECB via Frankfurter). Deterministic, keyless.

## Output

A set of exchange rate values for the requested currency pairs, derived from ECB reference data. Each rate represents how much of each target currency (symbols) equals one unit of the base currency.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "base",
  "symbols"
 ],
 "properties": {
  "base": {
   "type": "string",
   "description": "base"
  },
  "symbols": {
   "type": "string",
   "description": "symbols"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fx-rates-by-hergertsynthora-ecb-frankfurter-3c4ef441/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fx-rates.hergertsynthora.com](https://www.zero.xyz/host/fx-rates.hergertsynthora.com/llms.txt)