# Crypto Microdata for Agents

> Pay-per-call crypto + Base on-chain microdata for trading/onchain agents. No API key, no signup: GET a route, read 402 PAYMENT-REQUIRED, sign USDC (EIP-3009) on Base, retry with PAYMENT-SIGNATURE. Funnel: 1) GET /crypto/ping ($0.001) to test your x402 client; 2) /crypto/base-gas ($0.001, cheapest live Base gas) before any Base tx, /crypto/gas-compare ($0.002: which EVM chain is cheapest right now, Base/Ethereum/Arbitrum/Optimism/Polygon/BSC gas in USD per transfer/ERC-20/swap, cheapest first; 2.5x cheaper than $0.005 gas-compare APIs), /crypto/prices ($0.003, median of 4-5 venues), /crypto/market-pulse ($0.004: prices+funding+kimchi+Fear&Greed+regime in one call); 3) /crypto/funding-signal ($0.006: cross-venue funding Hyperliquid+OKX+Gate+dYdX, signal EXTREME_LONG..EXTREME_SHORT, best funding-arb pair), /crypto/hl-book?coin=BTC and /crypto/hl-funding ($0.005) for perps; 4) /crypto/token-risk?address=0x... ($0.01) answers 'should my agent buy this Base token?' with verdict OK|CAUTION|AVOID, should_buy, can_sell, reasons, /crypto/erc20-balance?token=&wallet= ($0.003), /crypto/wallet-snapshot?wallet= ($0.003, ETH+USDC+gas readiness in one call), /crypto/eth-balance?wallet= ($0.002), /crypto/allowance?owner=&spender= ($0.002: ERC-20 approval check on Base, unlimited flag, exposure = min(allowance, balance), known-spender label, revoke calldata; pass amount= for can_spend; cheaper than $0.003 allowance APIs), /crypto/tx-status?hash=0x.. ($0.002: did this Base tx succeed, who paid whom how much USDC, confirmations; pass expect_to=&expect_usdc= to verify a payment), /crypto/candles?symbol=BTC&interval=1h ($0.002: OHLCV klines + EMA20/50, RSI14, ATR14, trend and pullback zone; Binance>OKX>Hyperliquid>Coinbase>Kraken fallback, 3.75x cheaper than $0.0075 candle APIs), /crypto/perp-movers ($0.002: whole-market Hyperliquid scanner, top gainers/losers, funding extremes, OI/volume leaders, breadth; replaces 7 ranking calls), /crypto/kimchi-premium ($0.002), /crypto/prediction-markets?q=bitcoin ($0.003: live Polymarket odds as implied probabilities, 24h volume, liquidity, 1d move; 2.5x cheaper than $0.0075 prediction-market APIs, 404 = no match = not charged), /crypto/market-risk ($0.002: is anything breaking? ONE 0-100 market-stress score low|moderate|elevated|high from 5 legs: stablecoin peg+flows, BTC move+perp breadth, leverage/funding extremes, BTC volatility, Fear&Greed; returns main_driver, action and suggested_max_leverage; covers derivatives+sentiment that stablecoin-only risk scores skip), /crypto/global-market ($0.002: total crypto market cap, 24h volume, BTC/ETH dominance, DeFi TVL, total stablecoin supply + 1d/7d flow, Fear&Greed and a risk_on/risk_off regime in ONE call; cheaper than $0.003 market-cap-only APIs), /crypto/eth-rpc ($0.002: keyless Ethereum mainnet JSON-RPC, same batch-10 rules, 5x cheaper than ~$0.01 mainnet RPC APIs), /crypto/base-rpc ($0.002: keyless Base JSON-RPC, GET or POST, batch up to 10 calls per payment, 7-RPC failover; 2.5x cheaper than $0.005 x402 RPC gateways, up to 25x cheaper batched), /crypto/swap-quote?from=USDC&to=WETH&amount=10 ($0.003: best-route Base swap quote over 100+ DEX pools, cost %, gas USD, verdict, and with wallet= a ready-to-sign tx + approval check; quote first instead of paying flat $0.05 swap execution fees), /crypto/x402-check?url= ($0.002: should my agent pay this x402 endpoint? live unpaid probe of ANY x402 URL: decodes the 402 quote, real USD price, network, USDC-or-not asset, payTo EOA/contract + its Base USDC balance, scheme, timeout, Bazaar schema, latency, risk flags, verdict SAFE_TO_PAY|CAUTION|AVOID and within_budget for max_usd=; live check, not stored evidence, and 5x cheaper than $0.01 endpoint-recommendation APIs), /crypto/x-search?q= ($0.003: live X/Twitter posts + sentiment signal, for agents that cannot read X), /crypto/contract-info?address=0x.. ($0.002: what is at this address on Base/Ethereum? EOA vs contract vs 7702 wallet, ERC20/721/1155/Safe/proxy kind, token metadata, EIP-1967 implementation+admin, owner/renounced, risk flags; one call instead of three), /crypto/defi-tvl ($0.002: total + per-chain DeFi TVL with 1d/7d/30d flow, chain rank, protocol TVL, RISK_ON/OFF; one call instead of two $0.003 TVL/overview calls), /crypto/fear-greed ($0.001: Crypto Fear & Greed now + 30d history, 1d/7d/30d change, 7d/30d avg, streak, zone, contrarian signal; same price as bare-number F&G APIs, 5x cheaper than $0.005 ones), /crypto/stablecoin-peg ($0.001: is USDC/USDT/DAI on peg in bps, DEPEG alerts, stablecoin supply flow 1d/7d/30d = risk-on/off, Base supply). Every unpaid 402 also returns the accepts[] terms inline in the JSON body plus a free sample link. Try before you pay: add ?sample=1 to ANY paid route for a free static example of its exact JSON shape. Failed calls (4xx/5xx) are never charged (settlement only on 200). Every paid 200 carries a receipt.url (also X-Receipt-URL header): re-fetch that exact result free for 24h if your client drops the response. Free: /health, /openapi.json, /llms.txt, /catalog, /status.

## Start here (most useful first calls)
- GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/ping - $0.001 - test your x402 client end-to-end
- GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/gas-compare - $0.002 - cheapest EVM chain to execute on right now (Base, Ethereum, Arbitrum, Optimism, Polygon, BSC; USD per swap)
- GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/swap-quote?from=USDC&to=WETH&amount=10 - $0.003 - best Base swap route + ready-to-sign tx
- GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/token-risk?address=0x... - $0.01 - should my agent buy this Base token?
- GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/market-pulse - $0.004 - prices+funding+kimchi+Fear&Greed in one call
- POST https://kr-x402-mvp.kgy5612.workers.dev/crypto/base-rpc - $0.002 - keyless Base JSON-RPC, up to 10 calls per payment

## Paid endpoints (USDC on Base mainnet, x402)
### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/ping
- price: $0.001 USDC
- tags: x402, ping, test, heartbeat, crypto
- Paid heartbeat: cheapest way to test your x402 client end-to-end on Base USDC. Returns {ok:true,t,next}.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/ping?echo=my-agent-1
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/ping?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/token-risk
- price: $0.01 USDC
- tags: crypto, token-risk, token-verdict, should-buy, honeypot, can-sell, security, base, erc20, rug-check, token-verdict-api, token-analysis
- Should your agent buy this Base token? Half the price of $0.02 AI token-verdict quests, deterministic on-chain checks instead of an LLM opinion. One-call verdict OK|CAUTION|AVOID + should_buy + can_sell + plain-English reasons, backed by risk_score 0-100 + level, flags (honeypot, cannot_sell_all, high tax, mintable, hidden owner, proxy, blacklist, unverified), bytecode size, EIP-1967 proxy impl, owner(), buy/sell tax, honeypot simulation, top10 holder pct, holders. address=0x... (Base ERC-20).
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/token-risk?address=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/token-risk?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/erc20-balance
- price: $0.003 USDC
- tags: crypto, base, erc20, balance, onchain, wallet
- Live ERC-20 balance on Base: token=0x..&wallet=0x.. -> balance (decimals applied), raw, symbol, block.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/erc20-balance?token=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913&wallet=0xe4be4d0bd82d8e68203deff81f79ede0529f2617
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/erc20-balance?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/allowance
- price: $0.002 USDC
- tags: crypto, base, erc20, allowance, approval, revoke, approval-risk, permit2, wallet-security, onchain, defi
- ERC-20 approval check on Base: how much can spender move from owner? owner=0x..&spender=0x..[&token=0x.., default USDC][&amount=] -> allowance, unlimited flag, owner balance, exposure (min of allowance and balance), known spender label (Permit2, Uniswap, 1inch, 0x, Odos, Aerodrome), risk class, revoke_recommended + ready approve(spender,0) calldata, can_spend when amount= given. Use before transferFrom/swap, or to audit a wallet's dangerous approvals. Cheaper than $0.003 allowance APIs; 4xx/5xx never charged.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/allowance?owner=0xe4be4d0bd82d8e68203deff81f79ede0529f2617&spender=0x000000000022D473030F116dDEE9F6B43aC78BA3&token=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/allowance?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/wallet-snapshot
- price: $0.003 USDC
- tags: crypto, base, wallet, wallet-quick, payee-check, balance, usdc, eth, gas, onchain, x402, agent
- One-call Base wallet quick check (agent self-check or counterparty/payee check before you pay): native ETH + nonce + USDC balance + live gas cost of an ERC-20 transfer, and can_pay_gas / can_pay_x402 booleans. Cheaper than eth-balance + erc20-balance + base-gas separately ($0.006). wallet=0x..
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/wallet-snapshot?wallet=0xe4be4d0bd82d8e68203deff81f79ede0529f2617
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/wallet-snapshot?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/tx-status
- price: $0.002 USDC
- tags: crypto, base, transaction, tx-status, tx-decode, payment-verify, allowance, approval, revoke, approval-risk, permit2, receipt, usdc, erc20, x402, onchain, evm
- Did this Base transaction succeed, and who paid whom? hash=0x.. (64 hex) -> status success|failed|pending, block, confirmations, timestamp, from, to, ETH value, gas used + fee in ETH, method (transfer / approve / transferWithAuthorization / Multicall3 ...), is_x402_settlement (EIP-3009 AuthorizationUsed on USDC), and every decoded ERC-20 Transfer (token, symbol, from, to, amount with decimals). Optional expect_to=0x..&expect_usdc=0.01 returns payment_verified true|false (did expect_to receive >= that USDC in this tx). When to call: after sending a tx, before delivering goods for a payment, to confirm an x402 settlement, or to explain an unknown hash. Cheaper than generic tx-decode APIs ($0.003).
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/tx-status?hash=0x3ea6d07f7e990ba4c2289487cd12ea41b6e13b48518fa38b24de2afd1df1d8ca
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/tx-status?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/swap-quote
- price: $0.003 USDC
- tags: crypto, base, swap, swap-quote, dex, dex-aggregator, best-price, trade, buy-token, price-impact, slippage, calldata, approval, uniswap, aerodrome, kyberswap, defi, onchain, trading-agent
- How much will I get, and what do I sign? Best-route swap quote on Base for any token pair: from=USDC|ETH|WETH|cbBTC|DAI|AERO|DEGEN|BRETT|VIRTUAL or 0x.. &to=..&amount=10 (human units) [&wallet=0x.. for ready-to-sign calldata + approval check] [&slippage_bps=50]. Aggregates 100+ Base DEX pools (KyberSwap meta-aggregator, OpenOcean fallback). Returns amount_out, min_out after slippage, effective price, USD in/out, total cost % (price impact + fees), gas + L1 fee in USD, net_out_usd, DEX route, router (with known-router label), verdict GOOD|OK|POOR|AVOID. With wallet=: tx {to,data,value} to broadcast, current allowance to the router, needs_approval + exact approve calldata, and balance check. When to call: before any agent swap or token buy on Base, instead of paying a flat $0.05 swap execution fee. Pair with /crypto/token-risk (is the token safe) and /crypto/decode-calldata (verify the tx). 4xx/no-route never charged.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/swap-quote?from=USDC&to=WETH&amount=10
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/swap-quote?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/decode-calldata
- price: $0.002 USDC
- tags: crypto, base, calldata, abi-decode, tx-decode, function-selector, 4byte, pre-sign, approval-risk, unlimited-approval, permit, wallet-security, simulation, evm, onchain, agent-safety, x, twitter, x-search, social-sentiment
- What am I about to sign? Pre-sign calldata decoder for Base: data=0x.. (selector+args) [&to=0x.. token/contract for symbol+decimals] or hash=0x.. (decode an existing tx). Resolves the 4-byte selector (builtin + openchain + 4byte, collision-checked by ABI round-trip), returns function signature, typed args, plain-English summary, risk none|low|medium|high, flags (unlimited_approval, unknown_spender, approve_all_nfts, offchain_permit, permit2_allowance, batched_calls, inner_approval, eip3009_x402_settlement) and verdict SAFE_TO_SIGN|CAUTION|DANGER. Multicall/aggregate3 inner calls are decoded too. When to call: before an agent signs any tx or approval it did not build itself, or to explain an unknown tx input. 2.5x cheaper than $0.005 hash/keccak utilities and tells you what the bytes do. 4xx never charged.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/decode-calldata?data=0x095ea7b3000000000000000000000000000000000022d473030f116ddee9f6b43ac78ba3ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff&to=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/decode-calldata?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/candles
- price: $0.002 USDC
- tags: crypto, candles, ohlcv, klines, chart, technical-analysis, rsi, ema, atr, binance, trading, bitcoin, ethereum, solana, indicators
- OHLCV candlesticks (klines) for any major USDT pair with indicators precomputed, so your trading agent skips the math: symbol=BTC|ETH|SOL|BNB|XRP|DOGE|ADA|AVAX|LINK|SUI|... (or BTCUSDT), interval=1m|5m|15m|1h|4h|1d (default 1h), limit=10-500 (default 100). Returns candles [{t,o,h,l,c,v}] oldest->newest plus last close, change_pct over the window, EMA20, EMA50, RSI14, ATR14 (abs + pct), trend up|down|range, and a pullback zone EMA20 +/- 0.75*ATR (in_zone true/false). Source fallback Binance -> OKX -> Hyperliquid -> Coinbase -> Kraken -> Bybit (source field tells which). When to call: signal generation, backtest seed, stop/target sizing from ATR. 3.75x cheaper than $0.0075 candle endpoints; 60s cache.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/candles?symbol=BTC&interval=1h&limit=100
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/candles?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/prediction-markets
- price: $0.003 USDC
- tags: prediction-markets, polymarket, odds, implied-probability, event-odds, betting, crypto, bitcoin, macro, fed, election, forecast, sentiment
- Live prediction-market odds (Polymarket) as clean implied probabilities, so your agent can price events: q=bitcoin|ethereum|solana|fed|election|any keyword (default crypto), limit=1-20 events (default 8), markets=1-20 per event (default 6). Returns events sorted by 24h volume, each with markets [{question, outcome_label, yes_prob, no_prob, best_bid, best_ask, change_1d, volume_24h, liquidity, end_date, url}], contested markets (5-95%) first; plus top_contested (the most-traded genuinely uncertain market). When to call: hedge or size a trade on BTC/ETH price targets, read crowd odds on Fed/macro/election events, feed an event-driven strategy. 2.5x cheaper than $0.0075 prediction-market endpoints; no match returns 404 and is never charged; 60s cache.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/prediction-markets?q=bitcoin&limit=8
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/prediction-markets?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/perp-movers
- price: $0.002 USDC
- tags: crypto, perps, hyperliquid, top-movers, gainers, losers, screener, scanner, rankings, leaderboard, funding-rates, open-interest, momentum, market-breadth, trading
- Whole-market perp scanner (all ~200 Hyperliquid perps) in one call: top_gainers, top_losers, top_volume, top_open_interest, highest_funding (crowded longs), most_negative_funding (crowded shorts / squeeze candidates), unusual_activity (24h volume / OI), plus market breadth (advance_ratio, broad_rally|mixed|broad_selloff). Each row: coin, mark_px, change_24h_pct, volume_24h_usd, open_interest_usd, funding_apr_pct, premium_bps, max_leverage. When to call: pick what to trade this hour, find funding extremes, momentum or mean-reversion screens. limit=1-25 (default 10), min_volume_usd (default 1,000,000). Replaces 7 separate $0.002 ranking calls; 30s cache.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/perp-movers?limit=10
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/perp-movers?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/market-risk
- price: $0.002 USDC
- tags: crypto, market-risk, risk-score, market-stress, risk-off, risk-on, depeg, stablecoin, leverage, funding-rates, volatility, fear-greed, position-sizing, risk-management, circuit-breaker, trading
- Is anything breaking in crypto right now? One composite 0-100 market-stress score (low|moderate|elevated|high) with a per-leg breakdown: stablecoins (worst USDC/USDT/DAI peg deviation in bps + 7d supply flow), price & breadth (BTC 24h move + share of ~140 liquid Hyperliquid perps that are up), leverage (BTC funding APR + share of perps at extreme funding), volatility (BTC 1h ATR14 as % of price) and sentiment (Fear & Greed). Returns main_driver, anything_breaking, a plain-English action and suggested_max_leverage. When to call: once at the top of every trading, treasury or payment loop, before sizing a position, adding leverage or settling in a stablecoin. Unlike stablecoin-only risk scores it includes derivatives and sentiment. Needs >=3 live legs (otherwise 503, not charged); recomputed every 60s. Sources: DefiLlama, Kraken, Hyperliquid, Binance/OKX/Bybit, CoinLore, alternative.me.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/market-risk
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/market-risk?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/global-market
- price: $0.002 USDC
- tags: crypto, market-cap, crypto-market-cap, total-market-cap, btc-dominance, eth-dominance, bitcoin-dominance, defi-tvl, tvl, stablecoin-supply, stablecoin-flows, fear-greed, market-overview, market-regime, risk-on, macro
- Whole-crypto-market context in one call: total crypto market cap (USD) and 24h change, 24h trading volume, Bitcoin (BTC) and Ethereum (ETH) dominance, altcoin share, DeFi TVL across all chains, total USD stablecoin supply with 1d/7d flow (dry powder entering or leaving crypto), stablecoin share of market cap, Fear & Greed index, and a regime label RISK_ON|NEUTRAL|RISK_OFF with reasons. When to call: before acting on any single coin's move (is it the whole market or just this coin?), at the start of a trading or treasury loop, for daily market reports. Market cap + dominance + TVL + stablecoin flows that other APIs sell separately at $0.003 each. Sources: CoinLore (CoinGecko fallback), DefiLlama, alternative.me. 2-min cache.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/global-market
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/global-market?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/gas-compare
- price: $0.002 USDC
- tags: crypto, gas, gas-compare, gas-price, multichain, evm, base, ethereum, arbitrum, optimism, polygon, bsc, l2, fees, cheapest-chain, routing
- Which EVM chain is cheapest to execute on right now? Live gas price on Base, Ethereum, Arbitrum, Optimism, Polygon and BSC, converted to USD per native transfer (21k gas), ERC-20 transfer (65k) and swap (150k), sorted cheapest first, with cheapest chain, Ethereum-vs-cheapest multiple and a one-line recommendation. chains=base,ethereum,... to filter, gas=N for your own gas units. Multi-RPC failover per chain, native prices Binance>OKX>Coinbase, 30s cache. 2.5x cheaper than $0.005 gas-compare APIs; 5xx never charged.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/gas-compare
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/gas-compare?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/eth-rpc
- price: $0.002 USDC
- tags: crypto, ethereum, mainnet, l1, rpc, json-rpc, eth-rpc, node, eth_call, eth_getLogs, broadcast, onchain, evm, web3, infrastructure
- Pay-per-call Ethereum mainnet (chain 1) JSON-RPC, no API key, no account, paid in Base USDC: GET ?method=eth_call&params=[...] or POST a standard JSON-RPC body; POST a batch of up to 10 calls for ONE $0.002 payment (vs ~$0.01 per call at other x402 mainnet RPC APIs). Methods: eth_blockNumber, eth_chainId, eth_call, eth_estimateGas, eth_getBalance, eth_getTransactionCount, eth_getCode, eth_getStorageAt, eth_getTransactionByHash, eth_getTransactionReceipt, eth_getBlockByNumber, eth_getBlockByHash, eth_getLogs (<=2000 blocks), eth_gasPrice, eth_maxPriorityFeePerGas, eth_feeHistory, eth_sendRawTransaction, net_version. Failover across 7 public Ethereum RPCs; outage = 502 = not charged. Plain JSON-RPC 2.0 so viem/ethers work. When to call: your agent needs an L1 read (ENS, mainnet token balance, contract state, receipt) or to broadcast a signed mainnet tx.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/eth-rpc?method=eth_blockNumber&params=%5B%5D
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/eth-rpc?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/base-rpc
- price: $0.002 USDC
- tags: crypto, base, rpc, json-rpc, base-rpc, node, eth_call, eth_getLogs, broadcast, send-transaction, onchain, evm, web3, infrastructure
- Pay-per-call Base mainnet JSON-RPC, no API key, no account: GET ?method=eth_call&params=[...] (params = URL-encoded JSON array) or POST a standard JSON-RPC body. POST a batch of up to 10 calls for ONE $0.002 payment (vs $0.005 per call at other x402 RPC gateways). Read + broadcast methods: eth_blockNumber, eth_chainId, eth_call, eth_estimateGas, eth_getBalance, eth_getTransactionCount, eth_getCode, eth_getStorageAt, eth_getTransactionByHash, eth_getTransactionReceipt, eth_getBlockByNumber, eth_getBlockByHash, eth_getLogs (<=2000 blocks), eth_gasPrice, eth_maxPriorityFeePerGas, eth_feeHistory, eth_sendRawTransaction, net_version, web3_clientVersion. Failover across 7 public Base RPCs (drpc, publicnode, mainnet.base.org, tenderly, meowrpc, blastapi, llamarpc); upstream outage = 502 = not charged. Response is a plain JSON-RPC 2.0 result so any viem/ethers client works. When to call: your agent needs a raw Base read or to broadcast a signed tx without running or renting a node.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/base-rpc?method=eth_blockNumber&params=%5B%5D
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/base-rpc?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/x402-check
- price: $0.002 USDC
- tags: x402, x402-check, endpoint-trust, pre-payment-check, api-verification, agent-safety, payment-safety, trust, due-diligence, price-check, usdc, base, crypto
- Should my agent pay this x402 endpoint? Live pre-payment check of ANY x402 URL (never pays it): we GET the target unpaid and decode its 402 quote (PAYMENT-REQUIRED header for v2, JSON body for v1) -> x402 version, every accepts[] option with real USD price (atomic amount / decimals), network name, asset (is it canonical USDC on that chain?), scheme, payTo, maxTimeoutSeconds, resource URL match, Bazaar discovery schema present?, description, latency_ms and TLS. For Base payTo we add is_contract and its live USDC balance (has it ever been paid?). Risk flags (non_usdc_asset, price_over_budget, price_over_1usd, resource_host_mismatch, no_402, testnet_only, payto_zero, slow_response, no_schema) roll up to verdict SAFE_TO_PAY|CAUTION|AVOID, should_pay, cheapest_option and within_budget for max_usd=. When to call: before your agent pays an unfamiliar paid API, or to pick the cheapest of several. Live probe, not stale stored evidence, at 1/5 the price of $0.01 x402 recommendation APIs. https only, public hosts only; target unreachable = 502 = not charged.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/x402-check?url=https%3A%2F%2Fkr-x402-mvp.kgy5612.workers.dev%2Fcrypto%2Fping&max_usd=0.01
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/x402-check?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/defi-tvl
- price: $0.002 USDC
- tags: crypto, defi, tvl, defi-tvl, total-value-locked, chain-tvl, protocol-tvl, defi-overview, capital-flows, tvl-ranking, base, ethereum, solana, defillama, risk-on
- DeFi TVL in ONE call (others sell TVL and DeFi overview as two $0.003 calls): total DeFi TVL with 1d/7d/30d % change and flow inflow|flat|outflow, signal RISK_ON|NEUTRAL|RISK_OFF, top chains ranked by TVL with share %, Base rank+share; chain=Base|Ethereum|Solana|... adds that chain's TVL, rank, share and 1d/7d/30d flow; protocol=aave|lido|uniswap|aerodrome (DefiLlama slug) adds protocol TVL and share. limit=1-50 top chains (default 15). When to call: is capital entering or leaving DeFi / a chain before you deploy liquidity, pick a chain, or size a DeFi trade. Source DefiLlama, 5-10 min cache; unknown chain/protocol = 404 = not charged.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/defi-tvl?chain=Base
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/defi-tvl?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/contract-info
- price: $0.002 USDC
- tags: contract, contract-info, introspection, proxy, eip-1967, upgradeable, erc20, erc721, erc1155, nft, safe, multisig, eoa, eip-7702, owner, bytecode, base, ethereum, onchain, agent-safety, due-diligence, crypto
- What is at this address? One-call contract introspection on Base (default) or Ethereum (chain=eth): EOA vs contract vs EIP-7702 delegated wallet, bytecode size, kind ERC20|ERC721|ERC1155|SAFE_MULTISIG|PROXY|MINIMAL_PROXY|CONTRACT, token metadata (name, symbol, decimals, totalSupply), ERC-165 interfaces, upgradeable proxy detection (EIP-1967 implementation/admin/beacon slots, EIP-1167 clones) with the live implementation address, owner() and renounced flag, Safe threshold, native balance, plus risk flags (upgradeable, owner_can_change, unverifiable) and the next call to make. When to call: before approving, sending to, or trading against an unfamiliar address. Replaces 3 separate contract/proxy/code calls ($0.002-0.005 each elsewhere) with one $0.002 call. Bad address = 400 = not charged.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/contract-info?address=0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/contract-info?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/fear-greed
- price: $0.001 USDC
- tags: crypto, fear-greed, fear-and-greed, sentiment, sentiment-index, contrarian, market-sentiment, bitcoin, trading
- Crypto Fear & Greed Index with context, not just a number: value 0-100 + label now, previous reading, 1d/7d/30d change, 7d and 30d average, min/max 30d, streak (days in current zone), trend rising|falling|flat, contrarian signal BUY_FEAR|SELL_GREED|NEUTRAL, and optional history (days=1-30). When to call: daily summary, position sizing, or a sentiment gate before a trade. Same $0.001 as bare F&G APIs, 5x cheaper than $0.005 ones. Source alternative.me; 503 when down = not charged.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/fear-greed?days=7
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/fear-greed?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/stablecoin-peg
- price: $0.001 USDC
- tags: crypto, stablecoin, depeg, usdc, usdt, dai, peg, stablecoin-flows, risk, liquidity, base, market-risk
- Is USDC / USDT / DAI / USDe holding its $1 peg, and is stablecoin liquidity growing (risk-on) or shrinking (risk-off)? Top USD stablecoins: price, peg deviation in bps, status OK|DRIFT|WARN|DEPEG, Kraken cross-check for USDT/USDC/DAI, supply + 1d/7d change, dominance, supply on Base; plus total supply flow 1d/7d/30d, verdict ALL_PEGGED|WATCH|DEPEG_ALERT and alerts. When to call: before settling or parking funds in a stablecoin, as a systemic risk-off check in a trading loop. Optional symbols=USDC,USDT or top=1-30 (default 10). 5-min cache.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/stablecoin-peg?symbols=USDC%2CUSDT
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/stablecoin-peg?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/eth-balance
- price: $0.002 USDC
- tags: crypto, base, eth, balance, onchain, wallet
- Live native ETH balance + nonce for a wallet on Base: wallet=0x..
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/eth-balance?wallet=0xe4be4d0bd82d8e68203deff81f79ede0529f2617
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/eth-balance?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/kimchi-premium
- price: $0.002 USDC
- tags: korea, kimchi-premium, bitcoin, ethereum, upbit, crypto, fx
- Live Korea kimchi premium: Upbit KRW vs global USD (median of Coinbase, Kraken, Bitstamp) for BTC and ETH, plus USD/KRW FX. Korea crypto arb/sentiment signal. Optional symbols=BTC,ETH filter. Alias: /kr/kimchi-premium.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/kimchi-premium?symbols=BTC%2CETH
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/kimchi-premium?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/base-gas
- price: $0.001 USDC
- tags: crypto, base, gas, gas-oracle, gas-price, eip-1559, fee-estimate, maxFeePerGas, onchain, evm, transaction, l2
- Base gas oracle for agents sending Base txs: EIP-1559 slow / standard / fast tiers (maxFeePerGas + maxPriorityFeePerGas in gwei and wei hex, from eth_feeHistory 20 blocks p10/p50/p90), base fee, congestion 0-1, recommended_tier, ready-to-sign tx_fields, and est. cost in ETH + USD for your gas_limit (default 21000; use 65000 for an ERC-20 transfer). Cheapest paid call ($0.001).
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/base-gas?gas_limit=21000
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/base-gas?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/prices
- price: $0.003 USDC
- tags: crypto, prices, bitcoin, ethereum, solana
- Spot USD prices: median of Coinbase, Kraken, Bybit, Binance, CoinGecko (whichever respond) with n_sources, dispersion_bps, with 24h change/volume. symbols=BTC,ETH,SOL default; also BNB,XRP,DOGE,ADA,AVAX,LINK,SUI.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/prices?symbols=BTC%2CETH%2CSOL
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/prices?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/market-pulse
- price: $0.004 USDC
- tags: crypto, market-overview, sentiment, fear-greed, funding, kimchi-premium, regime, bitcoin, trading
- One-call crypto market regime for trading agents: BTC/ETH/SOL median spot + 24h change, Hyperliquid funding APR + open interest, Korea kimchi premium, Crypto Fear & Greed index, and a regime label (risk_on|neutral|risk_off) with plain reasons. Replaces 4 calls (prices+hl-funding+kimchi+sentiment, $0.015) for $0.004.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/market-pulse
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/market-pulse?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/funding-signal
- price: $0.006 USDC
- tags: crypto, funding-rates, funding-signal, perps, hyperliquid, okx, bitget, gate, dydx, bybit, binance, arbitrage, squeeze, positioning, trading
- Cross-exchange perp funding in one call: Hyperliquid + OKX + Gate + dYdX (+ Bybit/Binance/Bitget when reachable) funding APR per coin (BTC/ETH/SOL), mean APR, positioning signal EXTREME_LONG|LONG_HEAVY|NEUTRAL|SHORT_HEAVY|EXTREME_SHORT|MIXED, and the best funding-arb pair (short the highest venue, long the lowest) with spread APR. When to call: before opening a leveraged position, to spot squeeze setups, or to scan funding-divergence arbitrage. Optional coin=BTC.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/funding-signal?coin=BTC
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/funding-signal?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/hl-book
- price: $0.005 USDC
- tags: crypto, hyperliquid, perps, orderbook, trading
- Hyperliquid perp L2 top-of-book for coin=BTC|ETH|SOL: best bid/ask, mid, spread_bps, top N levels (depth=1-20, default 5).
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/hl-book?coin=BTC
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/hl-book?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/hl-funding
- price: $0.005 USDC
- tags: crypto, hyperliquid, perps, funding, open-interest
- Hyperliquid perp funding (hourly + APR), open interest (coins + USD), mark/oracle/mid px, 24h volume for BTC, ETH, SOL. Optional coin=BTC.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/hl-funding
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/hl-funding?sample=1

### GET https://kr-x402-mvp.kgy5612.workers.dev/crypto/x-search
- price: $0.003 USDC
- tags: x, twitter, x-search, social, sentiment, crypto-twitter, ct, social-signal, cashtag, news, crypto
- Live X (Twitter) search for agents that cannot read X: q=keyword|$TICKER|from:handle (X search operators ok), limit=1-20 (default 10), lang=en|ko|.., sort=recency|relevancy. Returns posts [{id,url,text,author{handle,name,followers,verified},metrics{likes,reposts,replies,quotes},created_at,lang}] plus signal {top_claim (most-engaged post: the tip/claim), sentiment bullish|bearish|neutral with score, top_terms, cashtags, notable_handles, engagement}. Last 7 days, no retweets. 4xx/5xx not charged.
- example: https://kr-x402-mvp.kgy5612.workers.dev/crypto/x-search?q=bitcoin&limit=10
- free sample (no payment): https://kr-x402-mvp.kgy5612.workers.dev/crypto/x-search?sample=1

## Free
- GET https://kr-x402-mvp.kgy5612.workers.dev/catalog — machine-readable product list
- GET https://kr-x402-mvp.kgy5612.workers.dev/pricing — all prices + cheaper bundles
- GET https://kr-x402-mvp.kgy5612.workers.dev/health — cache freshness
- GET https://kr-x402-mvp.kgy5612.workers.dev/status — per-route live readiness (upstream freshness) so you only pay for routes that are up
- ANY paid route + ?sample=1 — free static example of its response; failed calls (4xx/5xx) are never charged
- GET https://kr-x402-mvp.kgy5612.workers.dev/openapi.json — OpenAPI 3.1 + x-payment-info
- GET https://kr-x402-mvp.kgy5612.workers.dev/.well-known/x402 — resource fan-out
- GET https://kr-x402-mvp.kgy5612.workers.dev/receipt/{id} — free: re-fetch any paid response for 24h (id is in the paid JSON "receipt" field and X-Receipt-URL header)

## How to buy
1. GET a paid URL (expect HTTP 402 + Payment-Required header)
2. Sign exact USDC transfer (EIP-3009) to payTo on network eip155:8453
3. Retry with PAYMENT-SIGNATURE header; receive JSON