# Hermes Data API – Forex Rate Lookup

> Hermes Data API – Forex Rate Lookup is a paid API for AI agents from x402-api-blond.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-16).

Returns the current exchange rate between two currency pairs, sourced from exchangerate-api, for $0.01 USDC per call via x402 protocol.

## Facts

- Endpoint: POST https://x402-api-blond.vercel.app/forex/rate
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/hermes-data-api-forex-rate-lookup-946ea9a3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1oZ7sKRrJqOUzDJ0lKanM

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 hermes-data-api-forex-rate-lookup-946ea9a3 -d '<json body>'
```

Example prompt: What's the current exchange rate from USD to CNY? I need the live forex rate right now.

## When to prefer this

Choose this endpoint when you need a quick, low-cost ($0.01 USDC) spot forex rate lookup for any currency pair via a pay-per-call model with no subscription required. It is especially useful for AI agents operating in crypto-native environments already using the x402 payment protocol on Base, and when you also need sibling data (crypto prices, weather, A-share quotes) from the same Hermes API without managing multiple API keys.

## Known failure modes

- Unsupported or invalid currency codes return an error
- Payment failure via x402 protocol (insufficient USDC balance or incorrect payment header) results in 402 response
- Upstream exchangerate-api outage may cause delayed or unavailable rates
- Malformed request body (missing 'from' or 'to' fields) returns a validation error

## How this service works

Pay-per-call data API: crypto prices (CoinGecko), China A-share quotes (Sina), weather (Open-Meteo), forex rates, and Ethereum gas fees. Payments via x402 protocol, USDC on Base.

## Output

Returns a JSON object containing the source currency (from), target currency (to), the live exchange rate (rate), a Unix timestamp (ts) of when the rate was fetched, and the data source name (e.g. 'exchangerate-api').

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "toolName",
    "inputSchema"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "mcp"
    },
    "example": {
     "type": "object"
    },
    "toolName": {
     "type": "string"
    },
    "description": {
     "type": "string"
    },
    "inputSchema": {
     "type": "object"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "to": "CNY",
  "ts": 1750000000000,
  "from": "USD",
  "rate": 7.25,
  "source": "exchangerate-api"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/hermes-data-api-forex-rate-lookup-946ea9a3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-api-blond.vercel.app](https://www.zero.xyz/host/x402-api-blond.vercel.app/llms.txt)