Onchain & crypto

Ranks a wallet's active token approvals by USD-at-risk x unlimited-allowance x unlabelled-spender, and returns a prioritised revoke queue. Approvals are the #1 drain vector; this tells an agent exactly what to revoke first.

+4 more from 402.com.tr

Cheapest real end-to-end test of your pay-per-call (HTTP 402) client: pay US$0.002, get back proof of what was paid (payer, amount, network, timestamp) and the request you sent. Use it to check a wallet, a client library or a facilitator before buying something bigger.

+69 more from manylives.me

Buyers need confidence that wallet, agent card, domain label, MCP server, seller profile, and x402 receiver belong together.

+10 more from api.blockchainmoneymap.com

Token Inspector model pricing (per call)

Estimate token count

Use when an agent is about to swap on Base and needs the best executable price before committing funds. Flow best-execution quotes: compares Uniswap V3 and Aerodrome across fee tiers and returns the best venue, expected output, edge vs Uniswap baseline, block number, and an expiry window so the agent knows exactly how long the price holds.

+4 more from Flow

Current base fee + priority fee (gas price) for a chain (Alchemy). x402-paid, USDC on Base.

+11 more from api.cortexcloud.org

Why did my transaction fail? Give a chain and tx hash; get status, decoded method, gas used vs limit, fee, token transfers, events and, for failed transactions, the decoded revert reason (Error(string), Panic codes, custom errors resolved by signature) with a plain-language fix. Pending transactions get a stuck-transaction diagnosis (nonce gap, underpriced fee) and the replace/cancel recipe. Chains: ethereum, base, arbitrum, optimism, polygon, bsc.

+2 more from pitcrew-api.appin60.com

Live EIP-1559 gas on Ethereum, Base, Arbitrum, Optimism, Polygon or BNB: base fee, slow/standard/fast priority tiers from the last 20 blocks, ready-to-use maxFeePerGas values, and estimated cost of an ETH transfer, ERC-20 transfer, approve and Uniswap swap.

+4 more from contractlens-api.appin60.com

Current gas price on Base, Arbitrum, Ethereum or Optimism, with the USD cost right now of an ETH transfer, ERC-20 transfer, DEX swap and NFT mint. Use before sending a transaction to pick a chain or decide whether to wait.

+3 more from plainchain.appin60.com

Swap $0.10 of USDC on Base into sats on Bitcoin Lightning: pay this route over x402, name a Lightning address or a BOLT11 invoice for exactly the quoted sats (or with no amount), and the desk pays the sats within seconds with the preimage as the receipt. Testnet instance: Base Sepolia USDC in, Lightning testnet3 sats out.

Implied volatility (IV) of crypto options per expiry from Deribit, Bybit and OKX: ATM IV, 25-delta skew, put/call open interest ratio, max pain and Deribit's DVOL index; with an expiry, the options chain per strike with the greeks as each venue publishes them. Volatility surface inputs for BTC and ETH options. Data only. Bad input is free; nothing is charged when no venue answers.

One random joke, in English or Spanish, filtered by category: programming, crypto or general. Unlike the usual one-liner endpoints this one takes parameters, returns an id so you can exclude what you have already seen, and accepts a seed for a reproducible answer.

Check any wallet balance across 5 EVM chains. Returns native or ERC-20 balance with threshold check, block height, and on-chain receipt. Supports Base, Ethereum, Arbitrum, Optimism, and Polygon.

The cheapest way to test an x402 payment loop end to end. Returns the current Base block number and its hash. No parameters needed. Answered inline, no polling, with the Base block and hash it was read at. Valid 60s. Payment implies a request for immediate execution. Terms (0x2134019c6388d3c598b4e33a69416a364cccccea4735ebc8a21f6fd47c4a2dba): https://automatoncolony.xyz/api/v1/legal/terms

+6 more from Automaton Colony

Native and (optional) ERC-20 token balance for a wallet address across major EVM chains (base, ethereum, polygon, arbitrum, optimism)

Rank blockchains by total DeFi value locked (TVL) across all protocols

Pay FLINT $0.01 to scan a separate intended agent transaction before it executes; returns a signed decision record and a linked x402 service-payment receipt

ERC-20 token metadata: name, symbol, decimals and total supply for any token contract on Base, Polygon, Arbitrum, Optimism or Ethereum.

Read an ERC-20 token balance on Base. POST {"address":"0x...","token":"0x..."} and receive the raw balance, the token decimals and the human-readable amount. Defaults to USDC when token is omitted. Live chain state, no indexer lag.

Read the head of the Base chain, or a specific block. POST {} for the latest block, or {"number":12345678} for one by height. Returns number, hash, unix timestamp, gas used and transaction count. Useful as an authoritative chain clock.

Look up a transaction on Base by hash. POST {"hash":"0x..."} and receive its status, block number, from and to addresses, value, gas used and effective gas price. Returns a clear not-found rather than an empty object when the hash is unknown.

Read the native ETH balance of an address on Base. POST {"address":"0x..."} and receive the balance in wei and in ether. Live chain state read directly from a node, with no indexer lag and no API key.

Read ERC-20 metadata on Base. POST {"token":"0x..."} and receive the name, symbol, decimals and total supply, with the supply given both raw and decimal-adjusted. Reports a clear error when the address is not a token contract.

Determine whether an address on Base is a contract or an externally owned account. POST {"address":"0x..."} and receive isContract, the bytecode size in bytes and its keccak-256 hash. Useful before sending funds to an unfamiliar address.

Read the transaction count of an address on Base. POST {"address":"0x..."} with an optional {"pending":true} to include the mempool. Returns the nonce an agent should use for its next transaction.

Highest-yield DeFi pools across every chain and protocol, filterable by chain, project, or asset symbol: each pool returns TVL in USD, total APY with base/reward split, stablecoin flag, impermanent-loss risk, and exposure. Sort by APY or TVL, and set sustainable=true to exclude IL-risky pure reward-emission farms. Find where to earn yield on USDC, ETH, SOL and more. Sourced from DefiLlama.

Deep dive on any DeFi protocol by its DefiLlama slug (aave-v3, lido, uniswap…): current Total Value Locked, market cap, category, the chains it spans, a per-chain TVL breakdown, and a 30-day TVL history. Everything you need to size up a protocol in one call. Sourced from DefiLlama.

Decentralized exchange (DEX) trading volume ranked by protocol: 24-hour and 7-day volume in USD with 1d/7d change, plus the chains each DEX runs on. Pass ?chain=base to scope to one chain. See where on-chain trading is happening across Uniswap, Curve, Raydium, PancakeSwap and more. Sourced from DefiLlama.

GeckoTerminal-backed DEX pool liquidity and estimated trade slippage, plus fixed $1k/$5k/$10k slippage_tiers for at-a-glance depth checks - size a trade or compare pools before swapping, with a clearly-flagged constant-product approximation model. Paid in USDC on Base.