Historical daily exchange-rate series from the European Central Bank (via Frankfurter), with computed summary statistics. Pass base = 3-letter ISO 4217 currency (default USD), start = YYYY-MM-DD, optional end = YYYY-MM-DD (default = latest available), optional symbols = comma-separated target codes (default all), optional amount to scale rates (default 1). Range is capped at 366 days. Returns, per target currency, first/last/min/max/mean rate plus absolute and percentage change over the window, alongside the full daily series. ECB publishes on business days only; weekends and holidays are omitted.
/api/fx/timeseriesPAYMENT-SIGNATURE.The timeseries API is a pay-per-call fx endpoint built for AI agents and autonomous software. Historical daily exchange-rate series from the European Central Bank (via Frankfurter), with computed summary statistics.
There is no signup and no API key. An agent (or any HTTP client) hits the endpoint, receives an x402 "402 Payment Required" challenge, signs a sub-cent USDC payment on Base or Solana, and retries — the data comes back on the paid request. That makes it a drop-in timeseries data source for an agent tool-use loop, an MCP host, or a backend that needs fx data on demand without onboarding to yet another vendor portal.
| Name | Type | Description |
|---|---|---|
base | string | Base currency (3-letter ISO 4217). Default USD. match ^[A-Za-z]{3}$ |
symbols | string | Comma-separated target currency codes. Default: all available. min 3 chars · max 200 chars |
startrequired | string | Inclusive start date YYYY-MM-DD. match ^\d{4}-\d{2}-\d{2}$ |
end | string | Inclusive end date YYYY-MM-DD. Default: latest available. match ^\d{4}-\d{2}-\d{2}$ |
amount | number | Amount of base currency to scale rates by. Default 1. min 0 · max 1000000000 |
# 1. Probe with no auth → 402 envelope with PaymentRequirements curl -sS 'https://2s.io/api/fx/timeseries?base=USD&symbols=xxx&start=2024-01-01&end=2024-01-01&amount=1' # 2. Sign + retry with PAYMENT-SIGNATURE: curl -sS 'https://2s.io/api/fx/timeseries?base=USD&symbols=xxx&start=2024-01-01&end=2024-01-01&amount=1' \ -H 'PAYMENT-SIGNATURE: <base64-json-payload>' # Or use the canonical runner (handles probe → sign → retry): # EVM_PRIVATE_KEY=0x... node --env-file=.env.local \ # --experimental-strip-types scripts/x402-pay.ts \ # 'https://2s.io/api/fx/timeseries?base=USD&symbols=xxx&start=2024-01-01&end=2024-01-01&amount=1'
import { TwoS } from '@2sio/sdk'
const client = new TwoS({
privateKey: process.env.EVM_PRIVATE_KEY as `0x${string}`,
})
const result = await client.fx.timeseries({
"base": "USD",
"symbols": "xxx",
"start": "2024-01-01",
"end": "2024-01-01",
"amount": 1
})
console.log('endpoint:', result.endpoint)
console.log('cost:', result.costUsd, 'USDC')
console.log('tx:', result.settlement?.txHash)
console.log('data:', result.data)import os
from twosio import TwoS
client = TwoS(private_key=os.environ["EVM_PRIVATE_KEY"])
result = client.fx.timeseries(base="USD", symbols="xxx", start="2024-01-01", end="2024-01-01", amount=1)
print("endpoint:", result.endpoint)
print("cost:", result.cost_usd, "USDC")
print("tx:", (result.settlement or {}).get("tx_hash"))
print("data:", result.data)// 1. Add @2sio/mcp to your MCP host config (Claude Desktop example below).
// EVM_PRIVATE_KEY funds x402 payments per call.
// claude_desktop_config.json
{
"mcpServers": {
"2sio": {
"command": "npx",
"args": ["-y", "@2sio/mcp"],
"env": { "EVM_PRIVATE_KEY": "0x..." }
}
}
}
// 2. Once the server is running, agents call this tool via standard MCP:
{
"jsonrpc": "2.0",
"id": 1,
"method": "tools/call",
"params": {
"name": "fx.timeseries",
"arguments": {
"base": "USD",
"symbols": "xxx",
"start": "2024-01-01",
"end": "2024-01-01",
"amount": 1
}
}
}| Field | Type | Description |
|---|---|---|
ok | boolean | one of: true |
items | array | |
total | integer | Total matching rows upstream; null when unknown. |
source | object | |
meta | object |
{
"ok": true,
"items": [
{
"currency": "example",
"first": 1,
"last": 1,
"min": 1,
"max": 1,
"mean": 1,
"change": 1,
"pctChange": 1,
"count": 1
}
],
"total": 1,
"source": {
"provider": "example",
"url": "example",
"license": "example"
},
"meta": {
"base": "example",
"start": "example",
"end": "example",
"amount": 1,
"observations": 1,
"series": {}
}
}