String utilities. Transform one string every common way at once: camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, path/case, Title Case, Sentence case, upper and lower; a URL slug (accents removed); reversed; trimmed and whitespace-collapsed; and counts of characters, letters, digits, words and lines. Splits identifiers like userIDValue or XMLHttpRequest correctly. Use when naming fields, files and routes or cleaning user input.

Optimism account nonce. Read the transaction count (nonce) of a 0x address on Optimism, both confirmed and including pending transactions. Use to build the next transaction or to tell whether an address has ever sent anything; for its balance use op_balance. A malformed address is rejected with 400, uncharged.

Polygon PoS native balance. Native POL balance (eth_getBalance) of any 0x wallet address on Polygon PoS at the latest block, in wei and in POL. Use to check whether a wallet can pay gas or a transfer; for ERC-20 tokens use polygon_token_balance, for all holdings at once use wallet_portfolio. A malformed address is rejected with 400, uncharged.

Polygon PoS recent event logs. Recent contract event logs on Polygon PoS (eth_getLogs): the events a contract emitted over the last N blocks (1-1,000, default 50), optionally filtered by topic0 (the 0x 32-byte event signature hash). Returns up to 100 logs with block, transaction hash and topics. Use to watch transfers or contract events; for one transaction's outcome use polygon_receipt.

Gas history, Polygon gas price. Gas price history on Polygon PoS (eth_feeHistory): base fee in gwei for each of the last N blocks (5-100, default 20), how full each block was, and the 10th, 50th and 90th percentile priority fees, with the low, average and high base fee over the window. Use to judge whether fees are rising, pick a priority fee or time a transaction; for the current price alone use polygon_gas.

NFT balance, Polygon. How many NFTs of one ERC-721 collection a wallet holds on Polygon PoS (balanceOf), with the collection's name and symbol. Use to check a holder before a token-gated action or to see whether a wallet still holds a collection; for who holds one token id use polygon_nft_owner. Both inputs are 0x addresses; a missing contract is 404, a contract that is not ERC-721 422, both uncharged.

Polygon PoS contract check. Check whether a 0x address on Polygon PoS is a smart contract or a plain wallet: bytecode size, and whether it is an EIP-1167 minimal proxy and which implementation it points to. Use before sending funds or approving a spender; for a fuller risk verdict use check_counterparty. A malformed address is rejected with 400, uncharged.

NFT metadata, Polygon. NFT metadata on Polygon PoS: the token URI of one ERC-721 token id (tokenURI) and the JSON it points to (name, description, image, attributes), read from data: URIs, https or ipfs:// (through ipfs.io). Strings over 1,000 characters, such as on-chain SVG images, are shortened. Use to show or check what an NFT is; for its owner use polygon_nft_owner. A token that does not exist is 422, uncharged; unreachable metadata is reported in metadataError.

NFT owner, Polygon. Owner of an NFT on Polygon PoS: the wallet that holds one ERC-721 token id right now (ownerOf), plus the collection's name and symbol. Use to verify who holds an NFT before a trade, a mint gate or an airdrop; for how many a wallet holds use polygon_nft_balance, for the token's metadata polygon_nft_metadata. A missing contract is 404, a token that does not exist 422, both uncharged.

Polygon PoS account nonce. Read the transaction count (nonce) of a 0x address on Polygon PoS, both confirmed and including pending transactions. Use to build the next transaction or to tell whether an address has ever sent anything; for its balance use polygon_balance. A malformed address is rejected with 400, uncharged.

Estimate gas, Polygon. Estimate the gas a transaction would use on Polygon PoS (eth_estimateGas) and what it would cost at the current gas price, in gas units, gwei and POL. Give to, plus value in POL and calldata for a contract call, and the sender when the call depends on it. Use before sending a transaction or to price a batch; for the gas price alone use polygon_gas. A transaction that would revert is 422 with the reason, uncharged.

Proxy implementation, Polygon. Find the implementation behind a proxy contract on Polygon PoS: reads the EIP-1967 implementation, beacon and admin slots, EIP-1822 (UUPS), the older OpenZeppelin layout and EIP-1167 minimal-proxy bytecode, and names the kind found. Use before trusting or decoding a contract whose code can be swapped by its admin; for a fuller risk verdict use contract_risk. A malformed address is 400; an address without code is 404, both uncharged.

Polygon PoS transaction receipt. Transaction receipt on Polygon PoS (eth_getTransactionReceipt): success or reverted, gas used, effective gas price, fee paid in POL, number of event logs and any contract created. Use to confirm a payment or call went through; for sender, value and calldata use polygon_tx. Input is a 0x-prefixed 64-hex hash; a pending or unknown hash returns 404, uncharged.

Storage slot read, Polygon. Read one raw storage slot of a contract on Polygon PoS (eth_getStorageAt): the 32-byte word, as a number and, when it holds one, as an address. Slot is a decimal index or a 0x 32-byte key (mapping and proxy slots). Use to inspect contract state that has no getter, owners or implementation pointers; for proxies use polygon_proxy. A malformed address or slot is rejected with 400, uncharged.

Eth call, Polygon contract call. Read-only contract call on Polygon PoS (eth_call): send ABI-encoded calldata to a contract at the latest block and get the raw return data, without a transaction or gas. Use to read any view function that has no dedicated tool (the example reads USDC totalSupply, selector 0x18160ddd); decode the result with the function's ABI. Calldata up to 8 KB; a call that reverts is 422 with the reason, uncharged.

Polygon PoS gas price. Current gas price on Polygon PoS (eth_gasPrice): gas price, base fee and suggested priority fee in gwei, plus what a plain POL transfer (21,000 gas) costs right now. Takes no input. Use before sending a transaction or to decide whether to wait; for the fee a past transaction actually paid use polygon_receipt.

Polygon PoS transaction. Look up a Polygon PoS transaction by hash: sender, recipient, value in POL, nonce, gas limit, the 4-byte function selector and its block. Use to see what was sent or whether it exists; for success or failure and fees paid use polygon_receipt, for emitted events polygon_logs. Input is a 0x-prefixed 64-hex hash; an unknown hash returns 404, uncharged.

Use when an agent needs bazaar listing lint. Returns Quality-score an x402 Bazaar listing (0-100): live SSRF-guarded probe of the resource for a valid 402 challenge with description/output-schema/category/price-floor checks, plus snapshot-history analysis from daily full-catalogue Bazaar snapshots (price churn, delisting). $0.01.

Extract emails, URLs and more. Find all email addresses, URLs, phone-number-like strings, hashtags, @mentions and numbers in a text, each list de-duplicated. Use to pull contacts and links out of scraped pages or messages.

Use when an agent needs wallet transfers. Returns ERC-20 transfer history for one Base wallet, backed by the public Base transfer index: filter by token, direction and page, with normalized amounts, counterparties and timestamps; priced per bounded request $0.005/call via x402. $0.005.