# Czech National Bank (CNB) Exchange Rates

> Czech National Bank (CNB) Exchange Rates is a paid API for AI agents from x402.tuancodes.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-24).

Returns official CNB daily foreign exchange rates for a given date, sourced directly from the Czech National Bank's public API.

## Facts

- Endpoint: GET https://x402.tuancodes.workers.dev/cnb/rates?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/czech-national-bank-cnb-exchange-rates-d5bf07a4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DOOQlsq9OiIYOn45soT3M

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 czech-national-bank-cnb-exchange-rates-d5bf07a4
```

Example prompt: What's the official Czech National Bank exchange rate for euros to Czech koruna today? Pull the CNB daily fixing rates.

## When to prefer this

Choose this endpoint when you need authoritative, official CNB daily fixing rates sourced directly from the Czech National Bank (not estimated or third-party rates), especially for accounting, invoicing, VAT compliance, or any Czech regulatory context where the official CNB rate is legally required. Prefer this over generic forex APIs when Czech koruna (CZK) rates with official provenance and a specific fixing date matter.

## Known failure modes

- Date not yet published — CNB rates are published mid-morning on business days, so early-morning or weekend requests may return not-found (not charged)
- Non-business day requested — weekends and Czech public holidays have no fixing; returns not-found (not charged)
- Upstream CNB API timeout or 5xx — request is not charged and an error is returned
- Invalid date format — malformed date parameter may cause a 4xx error
- Future date beyond the current fixing — no rate available yet

## How this service works

Deterministic lookups from official public sources (ARES, EU VIES, Czech National Bank, GLEIF LEI index). No AI, no scraping. Pay per call in USDC on Base via x402. Requests that fail upstream (5xx/timeout) or not-found results are not charged.

## Output

Returns a JSON object with the base currency (CZK), a list of all foreign currencies with their code, country, currency name, unit amount, rate, and CZK-per-unit value, plus metadata including the source (Czech National Bank), the date the rates are valid for, the fixing order number, and the originally requested date.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "base": "CZK",
  "rates": [
   {
    "code": "EUR",
    "rate": 24.3,
    "amount": 1,
    "country": "EMU",
    "currency": "euro",
    "czk_per_unit": 24.3
   }
  ],
  "source": "Czech National Bank (api.cnb.cz)",
  "valid_for": "2026-10-13",
  "fixing_order": 197,
  "requested_date": "2026-10-13"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/czech-national-bank-cnb-exchange-rates-d5bf07a4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.tuancodes.workers.dev](https://www.zero.xyz/host/x402.tuancodes.workers.dev/llms.txt)