Foundry

Base contract brief: base-contract-facts plus a plain-English explanation of who controls the contract and what they can do (mint, freeze, blacklist, change fees, upgrade the code), with things to verify. Grounded only in on-chain facts; never investment advice. Input: 0x address.

ERC-20 token info on Base mainnet from the chain: name, symbol, decimals, total supply, and whether the address is a contract at all. Input: 0x token address. Deterministic, no LLM, cheapest token lookup.

x402 seller due diligence: everything in x402-preflight PLUS on-chain proof of real demand (USDC actually received by the seller's payTo in the last 24h: payments, distinct payers, volume) and a Bazaar listing-truth audit (is this URL listed, does the listed price match what it charges). Reveals dead, fake or mispriced sellers before payment.

Age calculator: age in years and days, next birthday and days until it. Input: a birth date 'YYYY-MM-DD'.

arXiv paper search: top 5 papers with authors, date, link and abstract. Input: search words.

Barcode validator: EAN-8, UPC-A, EAN-13 and GTIN-14 check digits. Input: barcode digits.

Base address lookup from the chain: wallet (EOA) or contract, bytecode size, ETH balance, USDC balance and number of transactions sent. Useful before sending funds or paying an address. Input: 0x address. Deterministic, no LLM.

Base contract fact sheet from the chain: is it a contract, proxy type (EIP-1967, beacon, EIP-1167 clone, ZeppelinOS) with implementation and admin, owner and whether ownership is renounced or held by a contract (multisig) or single key, privileged powers found in bytecode (mint, pause, blacklist, fee/tax setters, trading switch, tx limits, upgrade), current paused state, ERC-20 name/symbol/decimals/supply. Facts only, no verdict. Input: 0x address.

Current Base mainnet gas: latest block, base fee and priority fee in gwei, a suggested max fee, and the ETH cost of a typical USDC transfer. Input: any text, e.g. 'base'. Deterministic, no LLM.

Base transaction explained from the chain: success or reverted, block and time, from, to, ETH value, method selector, gas used and fee, contract created, and every ERC-20 transfer decoded with token symbol and amount. Input: 0x transaction hash. Deterministic, no LLM.

Base64 encoder and decoder, standard and URL-safe. Input: 'encode: text' or 'decode: aGVsbG8='.

Basename resolver: a .base.eth name to its Base address. Input: 'jesse.base.eth'.

Bible verse lookup (King James Version, public domain): text for a reference. Input: 'John 3:16'.

BMI calculator: body mass index and WHO category from weight and height. Input: 'weight kg, height cm'.

Business days between two dates: weekdays, weekend days and calendar days. Input: '2026-11-01 2026-11-30'.

Calendar: the days of any month laid out by week, with month length and first weekday. Input: 'YYYY-MM'.

Credit card number validator: Luhn checksum and card brand (Visa, Mastercard, Amex...). Format check only, never stored. Input: a card number.

EVM chain lookup: chain ID, name, native currency, public RPCs and explorers. Input: a chain ID or name.

Color converter: hex, RGB and HSL, luminance, contrast against white and black, best text color. Input: '#1e90ff'.

Country code lookup: ISO 3166 alpha-2, alpha-3 and numeric codes, official name, calling code and flag. Input: a country name or code.

Crypto news: the latest headlines with links from CoinDesk, Cointelegraph, Decrypt and Bitcoin Magazine, optionally filtered by keyword. Input: a keyword or 'latest'.

Crypto price in USD for up to 20 coins (BTC, ETH, SOL...) or tokens by chain:address, from DefiLlama. Input: 'BTC,ETH'.

Currency code lookup: ISO 4217 code, name and numeric code. Input: a code like 'PKR' or a currency name.

Date difference: days, weeks, months and years between two dates. Input: '2026-01-01 2026-12-25'.

DeFi TVL from DefiLlama: total value locked for a chain or protocol, or the top chains. Input: 'Base', 'aave' or 'top'.

DeFi yields: highest-APY pools with over $1M TVL, filtered by chain and token. Data only. Input: 'usdc base'.

Programming joke: one short, safe-for-work developer joke per call. Input: any text.

English dictionary: definitions, part of speech, phonetics and synonyms for a word. Input: a word.

DMARC record checker: policy, subdomain policy, percentage and report addresses for a domain. Input: a domain.

DNS lookup: A, AAAA, MX, TXT, NS, CNAME, SOA or CAA records for a domain, via DNS-over-HTTPS. Input: 'example.com MX'.

DNS propagation check: compares answers from Cloudflare and Google resolvers. Input: 'example.com A'.

Domain availability check via RDAP: is a domain registered or free. Input: a domain.

Recent earthquakes from USGS: magnitude, place, time and depth. Input: 'day', 'week' or 'significant'.

Email validation: syntax, MX records, disposable domain and role account checks. Input: an email address.

Emoji search: find emoji by keyword, with names and codepoints. Input: a word, e.g. 'rocket'.

ENS resolver: name to Ethereum address, or address to primary ENS name. Input: 'vitalik.eth' or a 0x address.

ERC-20 token balance for any wallet on Base, Ethereum, Arbitrum, Optimism or Polygon (USDC, USDT, DAI, WETH or any address), plus native balance. Input: 'wallet token chain'.

Favicon finder: a site's favicon and icon URLs. Input: a URL.

Crypto Fear and Greed Index: today's value and the last 7 days. Input: any text.

Currency exchange rates from the European Central Bank: convert an amount or list rates. Input: '100 USD to EUR'.

Gravatar lookup: whether an email has a Gravatar, with avatar and profile URLs. Input: an email address.

Hacker News top stories right now: title, link, points and comments. Input: how many, 1 to 10.

Hash generator: md5, sha1, sha256, sha512, sha3-256, blake2b and keccak256 of a text. Input: any text.

Web page to Markdown: the readable content of a URL as clean Markdown with links. Input: a URL.

HTTP status check: is a URL up, its status code, redirect chain, latency and server. Input: a URL.

IBAN validator: checksum (mod 97), country length check and formatted IBAN. Input: an IBAN.

Image info and EXIF: format, dimensions, colour mode, size and camera metadata of an image URL. Input: an image URL.

IP address info: public or private, reverse DNS, ASN, network name, prefix and country. Input: an IPv4 or IPv6 address.

Book lookup by ISBN: title, authors, publisher, date and pages from Open Library. Input: an ISBN.

JSON validator and formatter: checks JSON, reports the error line and column, returns pretty and minified forms. Input: JSON text.

JWT decoder: header, payload, issued and expiry times, and whether it has expired (signature not verified). Input: a JWT.

Language detection: the language of a text with confidence and alternatives. Input: any text.

Loan and mortgage calculator: monthly payment, total paid and total interest. Input: 'amount, rate %, years'.

Lorem ipsum placeholder text: 1 to 10 paragraphs. Input: number of paragraphs.

Math calculator: safely evaluates an expression with + - * / % ^, parentheses, pi, e and functions like sqrt, sin, log. Input: '2^10 + sqrt(16)'.

Random name generator: fictional names, usernames and example.com emails for test data. Input: how many, 1 to 20.

npm package info: latest version, license, dependencies count and weekly downloads. Input: a package name.

Number to words: spells out numbers in English, with a cheque-style amount. Input: '1234.50'.

OCR: extract all text from an image URL (photos, screenshots, scans, receipts, invoices) as Markdown; text PDFs read directly. Input: an image or PDF URL.

Password generator: a strong random password (8 to 128 characters) with its entropy. Input: length, e.g. '24'.

PDF text extractor: page count, title, author and text of the first 20 pages of a PDF URL. Input: a PDF URL.

Percentage calculator: X% of Y, X is what percent of Y, and percent change. Input: '15% of 200' or 'from 80 to 100'.

Phone number validator: validity, E.164 and international format, type, region, carrier and timezone. Input: '+44 20 7946 0958'.

Zip and postal code lookup: place names, state and coordinates for 60+ countries. Input: 'US 90210' or 'DE 10115'.

Prediction market odds from Polymarket: top markets by 24h volume, or those matching keywords, with implied odds, volume and end date. Input: keywords or 'top'.

Public holidays for a country and year, with the next upcoming one. Input: country code and year, e.g. 'US 2026'.

PyPI package info: latest version, license, Python requirement and recent downloads. Input: a package name.

QR code generator: PNG data URI and SVG for any text or URL. Input: the text or URL to encode.

Quote: a short public-domain quote with its author (Franklin, Seneca, Curie, Newton...). Input: a topic word or 'any'.

Random numbers from a secure RNG: integers in a range, dice like 2d6, or a coin flip. Input: '1 100', '1 100 5', '2d6' or 'coin'.

Readability: the main text of a web page with word count, reading time and Flesch reading ease. Input: a URL.

robots.txt checker: whether GPTBot, ClaudeBot, CCBot and other AI crawlers may crawl a site, plus sitemaps. Input: a domain or URL.

Roman numeral converter: numbers to Roman numerals and back (1 to 3999). Input: '2026' or 'MMXXVI'.

RSS and Atom feed reader: latest items with titles, links and dates. Input: a feed URL.

Sentiment analysis: positive, negative, neutral or mixed, with a score from -1 to 1. Input: any text.

Sitemap parser: URLs, child sitemaps and last-modified dates from a site's sitemap.xml. Input: a domain or sitemap URL.

Slug generator: turns any text into a clean URL slug. Input: a title.

SPF record checker: the SPF record, includes, DNS lookup count and all-mechanism policy for a domain. Input: a domain.

SSL certificate check: validity, issuer, expiry date and days left, SANs and TLS version. Input: a domain.

Stablecoin market data: circulating supply, peg and price for the largest stablecoins. Input: a symbol like 'USDC' or 'top'.

Summarize a text or a web page URL: one-sentence summary plus up to 5 key bullet points. Input: text (up to 6,000 characters) or a URL.

Sunrise and sunset times in UTC for a location and date, with day length. Input: 'lat,lon' or 'lat,lon,YYYY-MM-DD'.

Website tech stack detector: frameworks, CMS, analytics, CDN and server behind a site. Input: a URL.

Current time in any timezone: ISO time, unix timestamp, UTC offset, weekday. Input: IANA timezone, e.g. 'Europe/London'.

Timezone converter: convert a date and time between IANA timezones. Input: '2026-11-01 09:00 Europe/London to Asia/Karachi'.

Token list: verified token addresses and decimals on Base, Ethereum, Arbitrum and more (Uniswap list). Input: 'base usdc'.

Token verdict: send a Base token contract address, get an AI-written risk verdict with an A-F grade, score and flags (mint, blacklist, pause, fees, upgradeable, owner), plus DEX liquidity, volume and pool age. Not financial advice.

Translate text into any language, keeping formatting, names and numbers. Input: 'to Spanish: your text' (up to 2,000 characters; defaults to English).

US Treasury yields: the latest daily par yield curve from 1 month to 30 years, with the 10y-2y spread (U.S. Treasury, public domain). Input: any text.

Trivia questions with answers and options from the Open Trivia Database. Input: how many, 1 to 10.

Unicode character info: codepoint, official name, category, UTF-8 bytes and HTML entity. Input: characters or 'U+1F680'.

Unit converter: length, mass, volume, temperature, time, data size, speed, area, energy, pressure. Input: '10 km to mi'.

User agent parser: browser and version, OS, device type, and whether it is a bot or AI crawler. Input: a User-Agent string.

UUID generator: 1 to 50 random UUIDs, version 4 or time-ordered version 7. Input: '5' or 'v7 3'.

VIN decoder: make, model, year, trim, body, engine and plant from a vehicle identification number (NHTSA). Input: a 17-character VIN.

Weather now and the next hours for any location: temperature, wind, humidity, conditions (MET Norway). Input: 'lat,lon'.

Website metadata: title, description, Open Graph image, canonical URL, favicon and language of a page. Input: a URL.

Domain WHOIS via RDAP: registrar, creation and expiry dates, status and nameservers. Input: a domain.

Wikipedia summary: the lead extract and link for a topic. Input: a topic or article title.

Word count and text statistics: words, characters, sentences, paragraphs, reading time, top words. Input: any text.

x402 listing doctor for sellers: why a paid endpoint gets no buyers. Runs the x402 preflight, Coinbase's CDP validator, and presence checks in the CDP Bazaar and 402index, then returns concrete fixes: 402 before input validation, Bazaar metadata, description over 500 chars or instruction-like, slow or sleeping host, no settled sale yet. Input: endpoint URL, optionally 'POST <url>'. Deterministic, no LLM.

Daily x402 market report, measured on-chain: across 16 Bazaar topics, 80+ sellers, who earns (distinct payers, payments, USDC in 24 h), how many earn nothing, listing price bands, total USDC, distinct buyers and the biggest buying wallets. Refreshed hourly. Input: any text, e.g. 'today'. No LLM.

x402 market scan: for a topic, the top CDP Bazaar listings and who actually gets paid, measured on-chain: each seller's USDC received in the last 24 hours, payments and distinct payers, plus how many sellers earned nothing and the median price. Real demand before you build. Input: a topic, e.g. 'token security'. No LLM.

x402 preflight: checks a paid x402 endpoint before a payment is signed. Probes it unpaid, parses the v1 body or v2 PAYMENT-REQUIRED header, lints every accepts[] option (network, canonical USDC, EIP-712 domain name/version that signatures verify against, EIP-55 payTo, zero payTo, amount, timeout, testnet, resource host) and returns ok/warn/block with reasons. Input: URL, optionally 'POST <url>'. Deterministic, no LLM.

Real x402 demand from the chain: USDC an address (e.g. a seller's payTo) received on Base in the last 24 hours, with payment count, distinct payers, total, and top payers with the largest payer's share (a high share suggests self-testing or wash volume). Input: 0x address. Deterministic, no LLM.