# 3HZ Daily FX Reference Rate

> 3HZ Daily FX Reference Rate is a paid API for AI agents from wallet-services-poc-clean-mainnet.3hz-services.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-19).

Returns the ECB/Frankfurter daily reference exchange rate between any two ISO 4217 fiat currency codes.

## Facts

- Endpoint: GET https://wallet-services-poc-clean-mainnet.3hz-services.workers.dev/fx-rate
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/3hz-daily-fx-reference-rate-82f615ff
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3cyAPlYE09zimo5nGG2nr

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 3hz-daily-fx-reference-rate-82f615ff
```

Example prompt: What's today's ECB reference rate for converting EUR to USD? I need the official daily rate for our accounting reconciliation.

## When to prefer this

Choose this endpoint when you need an authoritative, ECB-sourced daily reference rate for accounting, financial reporting, invoice normalization, or expense reimbursement — not for live trading prices or intraday FX quotes. It is ideal when regulatory or audit requirements demand a stable, official reference rate rather than a market spread.

## Known failure modes

- Unsupported currency code returns an error — only ECB-published currencies are available
- Invalid three-letter code format (e.g. numeric or empty string) is rejected by schema validation
- Weekend or holiday dates may return the most recent available ECB business day rate rather than today's date
- Payment failure (x402) if USDC balance is insufficient — endpoint returns 402 before serving data
- Network timeout on the upstream Frankfurter/ECB feed may delay or fail response

## How this service works

Daily reference foreign-exchange rate for any supported fiat currency pair using Frankfurter/ECB reference data. Query base and quote ISO 4217 codes. For conversion, normalization, accounting and reporting; not live trading data.

## Output

A JSON object containing the base currency code, quote currency code, the numeric exchange rate (how many units of quote per 1 unit of base), the date the rate applies to, the data source name and URL, the rate type label, and the timestamp when the rate was fetched.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input",
  "output"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "base": {
       "type": "string",
       "default": "EUR",
       "pattern": "^[A-Za-z]{3}$",
       "description": "Three-letter base currency code"
      },
      "quote": {
       "type": "string",
       "default": "USD",
       "pattern": "^[A-Za-z]{3}$",
       "description": "Three-letter quote currency code"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type",
    "example"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "json"
    },
    "example": {
     "type": "object",
     "required": [
      "base",
      "quote",
      "rate",
      "date",
      "source",
      "source_url",
      "rate_type",
      "fetched_at"
     ],
     "properties": {
      "base": {
       "type": "string"
      },
      "date": {
       "type": "string"
      },
      "rate": {
       "type": "number"
      },
      "quote": {
       "type": "string"
      },
      "source": {
       "type": "string"
      },
      "rate_type": {
       "type": "string"
      },
      "fetched_at": {
       "type": "string"
      },
      "source_url": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  }
 },
 "additionalProperties": false
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/3hz-daily-fx-reference-rate-82f615ff/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from wallet-services-poc-clean-mainnet.3hz-services.workers.dev](https://www.zero.xyz/host/wallet-services-poc-clean-mainnet.3hz-services.workers.dev/llms.txt)