Onchain Data APIs

Chainlink For Agents: execute a catalog workflow by workflow name.

Chainlink For Agents: submit a signed operation payload.

Get SmartMoney trading activities on token (sorted by time descending)

Send a Base token contract address, get an AI-written verdict: onchain metrics, a plain-language take, and a shareable verdict card. Entertainment, not trading advice.

Get KOL trading activities on token (sorted by time descending)

Get Whale trading activities on token (sorted by time descending)

Token safety analysis for a Solana mint: overall risk level, wallet-network concentration, bundle detection, mintable/freezable flags, critical risks, and warnings. Returns the most recent cached analysis.

Nansen · Address Current Balance

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Get Address Current Balance Data

Latest Ethereum block height - current chain tip via eth_blockNumber

ERC20 token balance for any Ethereum wallet - USDC, USDT, DAI, or any token - via balanceOf (eth_call) on OneSource live Ethereum RPC

ENS resolve - turn a .eth name into an address, or an address into its primary .eth name, via eth_call on OneSource live Ethereum RPC

Live wallet balance - native ETH plus up to 20 caller-supplied ERC20 tokens in one bounded RPC batch

Full Ethereum transaction details by hash via eth_getTransactionByHash - from, to, value, calldata, block

Live Base mainnet gas: EIP-1559 base fee, low/medium/high priority tiers in gwei, and a transaction cost estimate for any gas limit.

Best-effort contract introspection via batched RPC - bytecode presence, token metadata, and ERC20-like/ERC721/ERC1155 classification

List every ERC721 NFT token_id a wallet owns in a collection via tokenOfOwnerByIndex (eth_call)

Fetch an Ethereum block header and transaction hashes by number, tag, or hex via eth_getBlockByNumber

Next transaction nonce for any Ethereum wallet via eth_getTransactionCount - how many txs it has sent

Total supply of an ERC20 or ERC721 token contract via totalSupply (eth_call)

ERC20 Transfer logs via eth_getLogs - raw Transfer events for a token or wallet

NFT metadata for ERC721 or ERC1155 tokens via eth_call, with IPFS, Arweave, data URI, and public HTTP(S) resolution

Transaction receipt via eth_getTransactionReceipt - status, gas, and event logs for a mined Ethereum transaction

Nansen · Token Screener

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Retrieve token screener data

Is this tokenized stock safe to buy? Pre-trade RWA check before an agent buys an on-chain US stock. ?symbol=AAPLx or ?address= returns ok/review/avoid + AUTHENTICITY - the REAL issuer token or an IMPERSONATOR? Verified against Backed/xStocks' registry and Ondo's on-chain mint authority. Plus depeg_bps, liquidity, trading_halted, freeze_authority. ?underlying=TSLA compares every verified version across issuers; ?watch=a,b returns only what CHANGED.