calendar.holidays

List the official holidays for a country and year, with exact observed dates including substitute days (e.g. a Saturday July 4th observed on Friday). Query: country (ISO 3166-1 alpha-2, 200+ supported), year, optional region (subdivision code like CA for US-California or BY for DE-Bavaria), optional types filter (public, bank, school, optional, observance — comma-separated), optional lang (ISO 639-1) for localized names. Returns one item per holiday: { date (YYYY-MM-DD), name, type, substitute, rule }. Dates are computed from maintained per-country rules — including movable feasts and lunar-calendar holidays — so they stay correct year over year. Use for scheduling, delivery estimates, payment terms, and SLA math.

price

$0.0010 USDC per call

method

GET/api/calendar/holidays

payment

x402 v2 · USDC on Base (EIP-3009) or Solana (SPL transfer)

auth

None. Sign the payment, retry with PAYMENT-SIGNATURE.

tier

Tier 0 — no paid upstream

Parameters

Name	Type	Description
`country`required	string	ISO 3166-1 alpha-2 country code, e.g. US, DE, JP. 200+ countries supported. min 2 chars · max 2 chars
`year`required	integer	Calendar year (1950-2100). min 1950 · max 2100
`region`	string	Optional subdivision code — e.g. CA for US-California, BY for DE-Bavaria, ON for CA-Ontario. min 1 chars · max 10 chars
`types`	string	Optional comma-separated holiday-type filter: public, bank, school, optional, observance. Default: all types. max 60 chars
`lang`	string	Optional ISO 639-1 language code for localized holiday names, e.g. en, de, fr. min 2 chars · max 5 chars

Code samples

cURLbash

# 1. Probe with no auth → 402 envelope with PaymentRequirements
curl -sS 'https://2s.io/api/calendar/holidays?country=xx&year=1950&region=example&types=example&lang=xx'

# 2. Sign + retry with PAYMENT-SIGNATURE:
curl -sS 'https://2s.io/api/calendar/holidays?country=xx&year=1950&region=example&types=example&lang=xx' \
  -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/calendar/holidays?country=xx&year=1950&region=example&types=example&lang=xx'

TypeScript / Node — @2sio/sdktypescript

import { TwoS } from '@2sio/sdk'

const client = new TwoS({
  privateKey: process.env.EVM_PRIVATE_KEY as `0x${string}`,
})

const result = await client.calendar.holidays({
  "country": "xx",
  "year": 1950,
  "region": "example",
  "types": "example",
  "lang": "xx"
})

console.log('endpoint:', result.endpoint)
console.log('cost:', result.costUsd, 'USDC')
console.log('tx:', result.settlement?.txHash)
console.log('data:', result.data)

Python — 2siopython

import os
from twosio import TwoS

client = TwoS(private_key=os.environ["EVM_PRIVATE_KEY"])

result = client.calendar.holidays(country="xx", year=1950, region="example", types="example", lang="xx")

print("endpoint:", result.endpoint)
print("cost:", result.cost_usd, "USDC")
print("tx:", (result.settlement or {}).get("tx_hash"))
print("data:", result.data)

MCP — Claude Desktop / AgentKit / any MCP hostjson

// 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": "calendar.holidays",
    "arguments": {
      "country": "xx",
      "year": 1950,
      "region": "example",
      "types": "example",
      "lang": "xx"
    }
  }
}

Response

Field	Type	Description
`ok`	boolean	one of: true
`items`	array
`total`	integer	Total matching rows upstream; null when unknown.
`source`	object

Example response datajson

{
  "ok": true,
  "items": [
    {
      "date": "example",
      "name": "example",
      "type": "example",
      "substitute": false,
      "rule": "example"
    }
  ],
  "total": 1,
  "source": {
    "provider": "example",
    "url": "example",
    "license": "example"
  }
}

Discovery

/api/directory — full catalog of every endpoint
/openapi.json — OpenAPI 3.1 spec (per-op x-payment-info, x402Payment security)
/.well-known/x402 — machine-readable service descriptor for x402-aware crawlers
/.well-known/mcp/server-card.json — MCP SEP-1649 server card
/llms.txt — plain-text manifest for LLM ingestion

2s.io is x402-native. Every call is paid per-request from a USDC-funded EVM wallet on Base — no signup, no API keys, no monthly fees. Source code: github.com/2s-io/sdk.