k-data-mcp
MCP server for Korean market data, metered per call in USDC over x402. No account, no API key, no signup โ the server pays each request from a wallet you supply.
What you get
- Kimchi premium on a tradeable basis. Everyone quotes the premium against the official USD/KRW rate, but Korean capital controls mean the KRW exit leg actually goes through USDT โ so that number is not something you can trade on. This returns both, and they routinely disagree in sign: official can read โ0.27% while the realizable basis is +0.19%.
- Premium history and percentile context. A continuously recorded archive answers "is this premium unusual right now?" โ percentile, mean, stdev, z-score over 1hโ90d. No free source publishes this, and it cannot be reconstructed after the fact.
- Korean headlines translated to English, from Yonhap, Maeil Business and Hankyung. Korean myriad units (์ต / ์กฐ) are expanded deterministically before translation, so "989์ต๋ฌ๋ฌ" comes back as $98.9 billion rather than the 10ร-off answer language models produce unaided.
- Upbit KRW quotes and market summaries, USD/KRW.
Install
Claude Desktop / Claude Code
{
"mcpServers": {
"k-data": {
"command": "npx",
"args": ["-y", "k-data-mcp"],
"env": {
"K_DATA_PRIVATE_KEY": "0xYOUR_DEDICATED_WALLET_KEY",
"K_DATA_MAX_SPEND_USD": "1"
}
}
}
}
Wallet setup
Each tool call spends real USDC, so the server will not start without a key and a budget.
- Create a dedicated wallet โ not your main one. The key sits in a config file and every call spends from it.
- Fund it with the USDC you're willing to spend on Base. No ETH needed: x402 settles with an off-chain EIP-3009 signature and the facilitator pays the gas.
- Set
K_DATA_MAX_SPEND_USD. The server refuses any call that would push cumulative spend past it.
| Variable | Required | Default | Meaning |
|---|
K_DATA_PRIVATE_KEY | yes | โ | Private key of the paying wallet (USDC on Base) |
K_DATA_MAX_SPEND_USD | no | 1 | Hard cap on cumulative spend for the session |
K_DATA_BASE_URL | no | hosted service | Point at a different K-Data deployment |
list_endpoints is free โ call it first to see current prices and decide what's worth buying.
| Tool | Price | Returns |
|---|
list_endpoints | free | Catalog, current prices, wallet address, remaining budget |
kimchi_premium | $0.03 | Dual-basis premium (official + USDT) for up to 10 coins |
kimchi_premium_stats | $0.12 | Percentile, mean, stdev, z-score of the premium over 1hโ90d |
kimchi_premium_history | $0.08 | Premium time series, both bases |
korea_market_snapshot | $0.08 | One-call briefing: premium + markets + FX + translated headlines |
news_headlines_en | $0.05 | Korean headlines with English translations |
crypto_krw_markets | $0.01 | All Upbit KRW markets โ volume leaders, gainers, losers |
news_headlines | $0.01 | Korean headlines, untranslated |
crypto_krw_ticker | $0.005 | One Upbit KRW quote |
fx_usdkrw | $0.005 | USD/KRW rate |
Prices are read from the provider's catalog at startup, so this table reflects whatever the service currently charges.
How payment works
Every paid endpoint answers an unpaid request with HTTP 402 and a PAYMENT-REQUIRED header describing the price, asset and recipient. This server signs an EIP-3009 authorization for that exact amount and retries; the facilitator settles it on Base. Nothing is held on account โ you pay per call, and stop paying when you stop calling.
License
MIT