SiteCheck

A GitHub user's public profile (name, company, location, blog, bio, followers, public repos, creation date) and their five most-starred repositories that are not forks.

Searches open prediction markets on Polymarket (real money, USDC) and Manifold (play money) by keywords, with optional closing-date window and minimum volume. Each row: venue, question, outcomes with prices (implied probability), volume with its unit (USD or mana), liquidity, close time and link. Results alternate between venues; up to 50 rows. Information only, not financial advice.

Company contact enrichment from a domain: emails (same-domain flagged), phones, social profiles, description and tech stack, read from the home, contact, about and legal pages.

Official rate and macro series in one call, by name: fed_funds, us_cpi, us_core_cpi, us_unemployment, us_10y, us_2y, us_mortgage_30y, us_gdp, wti_oil, brent_oil, henry_hub_gas, us_house_price_index, ecb_deposit_rate, ecb_main_refi_rate and euro_area_hicp. Latest value, change vs previous and vs a year earlier, and observations. Up to 6 series. FRED (US public domain), the ECB Data Portal and Euros

A QR code for a text of up to 300 characters (a URL, Wi-Fi login or contact card), generated locally. format=svg returns the image itself as image/svg+xml; format=json returns the version, the module count, the SVG and a data URI. Error correction L, M, Q or H (default M); size from 128 to 1024 pixels (default 512).

Markdown to HTML with GitHub-flavoured tables and strikethrough, heading ids, the list of headings and links, and a word count. Raw HTML in the input is escaped unless allowHtml is true; links and images with javascript:, vbscript: or data: addresses are removed. Pure code, no outbound request. Input up to 200 KB.

Read-only JSON-RPC pass-through for 20+ EVM chains (ethereum, base, arbitrum, optimism, polygon, bsc, avalanche, gnosis, linea, scroll, zksync, mantle, blast, celo, fantom, sonic, unichain, opbnb, zora, mode, metis, cronos). Single or batch calls (up to 10). Write methods refused.

Multilingual text embeddings (BGE-M3, 1024 dimensions) for up to 100 texts per call. For search, RAG and clustering.

Split a long text into chunks for retrieval (RAG): split on paragraphs, then sentences, then words, each chunk within maxTokens (default 500) with the overlap you ask for (default 50 tokens). Each chunk has its index, text, start and end character offsets and an estimated token count (characters divided by 4, a rough rule for English). Up to 1 MB and 2,000 chunks.

Hashes of a text or base64 input (up to 1 MB): MD5, SHA-1, SHA-256, SHA-384, SHA-512 and CRC-32, and HMAC-SHA-256 or HMAC-SHA-512 when a key is given. Hex and base64 output. MD5 and CRC-32 are implemented here and checked against RFC 1321 and the standard CRC test vector. Body { input, encoding, algorithms, key }. Pure code and WebCrypto, no outside request.

Repairs broken JSON: markdown fences, comments, trailing commas, single quotes, unquoted keys, Python literals (True, False, None) and truncated endings. Pure code first; the model is asked once only when code cannot repair it. Optional JSON Schema check covers type, required, properties, items, enum, minimum, maximum, minLength, maxLength and pattern. Input max 1 MB.

Validates JSON data against a JSON Schema (draft 2020-12): valid true or false, and up to 50 errors with the instance path, the keyword and the message. Schema and data are each limited to 200 KB. Remote $ref targets are not fetched. No network call.

Currency exchange rates from the European Central Bank (about 30 currencies, back to 1999): latest or a given date, amount conversion, or a daily time series between two dates. Source: ECB reference rates via Frankfurter.

Read-only JSON-RPC pass-through for Solana mainnet. Allowed methods: getAccountInfo, getBalance, getTransaction, getSignaturesForAddress (limit <= 100), getTokenAccountsByOwner, getTokenSupply, getSlot, getBlockTime, getLatestBlockhash, getMultipleAccounts (<= 20). Write methods and getProgramAccounts refused.

Daily or monthly page views (user agent, all access) for up to 5 articles in one Wikipedia edition over a date range of at most one year, with totals, peak day and the change between the first and second half. mode=top lists the most viewed articles of one day. Data lags by about a day; bots and unknown agents are excluded.

IBAN validation with no network call: ISO 13616 length and structure for every country in the SWIFT IBAN registry, the mod-97 checksum, national check digits where a public algorithm exists (FR, ES, IT, BE, NL, NO, FI, PL, PT and the Balkan countries), and the split into bank code, branch code and account. Returns the electronic and print format. Pass ibans= for up to 50 at once. No bank name or B

Mail and DNS hygiene of a domain over DNS over HTTPS: A, AAAA, MX, NS, TXT and CAA records; SPF parsed (mechanisms, the all qualifier, a lookup estimate, a warning above 10 lookups); the DMARC policy; DKIM keys under common selectors; MTA-STS, TLS-RPT and BIMI; an issues list and a mail grade from A to F.

Domain lookup over RDAP (the successor of WHOIS) and DNS: registered or available, registrar, creation, update and expiry dates, days until expiry, age, status codes, DNSSEC, name servers, plus whether it resolves (IPv4/IPv6) and its mail servers. Any TLD with an RDAP service; others are inferred from DNS.

Flight fares for one route and date, one-way or round trip: the cheapest, the fastest and the cheapest nonstop option, then up to 20 itineraries sorted by price with carrier, stops, duration, departure and arrival times (local and UTC), every flight segment and aircraft. Cabin, maximum stops and market (sets the currency) are optional. Fares for a single traveller from Ignav; a fare search, not a

Key figures per fiscal year or quarter from a company's SEC XBRL filings, the numbers it tagged itself: revenue, net income, operating income, assets, liabilities, equity, cash, operating cash flow, diluted EPS and shares outstanding. Each value carries the form and filing date it came from. Ticker or CIK. Source: SEC XBRL API, public domain.

E-mail pre-check without SMTP: syntax, whether the domain can receive mail (MX or implicit MX, null MX, non-existent domain), disposable domain (9,000+ domain CC0 list), role account (info@, sales@...), free provider and a typo suggestion (gmial.com -> gmail.com). Verdict invalid / risky / unknown. Up to 50 addresses per call with emails=.

Airport lookup in a bundled OurAirports extract (public domain, dated in the answer): by IATA or ICAO code, by name or city words, or the nearest airports within a radius (up to 300 km) of a point. Covers large and medium airports and every airport with an IATA code; small airports without one are left out. Name, codes, type, city, country, coordinates, elevation and Wikipedia link. No time zone (

The redirect chain of a URL, hop by hop (at most 10 hops): each URL, its status, the Location it points to, and whether the hop goes from http to https or changes host. Returns the final URL and status, total hops, loop true when a URL repeats, and the Strict-Transport-Security header of the final response.

Perpetual futures funding for one coin across Hyperliquid, OKX, Deribit and dYdX v4: the current funding rate, the interval (1 or 8 hours), the annualised rate, the next funding time, open interest in coins and USD, and the mark or oracle price. A venue that does not list the coin is left out and named in unavailable. Rates are as the venues publish them; funding is paid between traders, not to th

Security headers of a URL's final response: Strict-Transport-Security, Content-Security-Policy, X-Frame-Options (or CSP frame-ancestors), X-Content-Type-Options, Referrer-Policy, Permissions-Policy, Cross-Origin-Opener-Policy and Cross-Origin-Resource-Policy, each with present, value, ok and advice. Also cookies missing Secure, HttpOnly or SameSite (names only), version leaks in Server or X-Powere

Hacker News stories or comments from the Algolia search API: keyword search (q) or the current front page (mode=front), optionally since a date. Stories give title, URL, HN link, points, comments, author and time. Comments give their text (400 characters, HTML stripped) and the story title. Up to 50 results. Public data, no key.

The language of a text with franc-min: ISO 639-3 and ISO 639-1 codes, the English name, confidence from 0 to 1, the script (Latin, Cyrillic, Arabic...) and the three next most likely languages. Send texts= (a JSON array of up to 20 strings) for a batch. Under 20 characters the answer is und with a note. 61 languages.

SEO and sharing metadata of one web page, read from its HTML without JavaScript: final URL and status, title and description with their lengths, canonical, robots meta, lang, hreflang, Open Graph and Twitter card tags, JSON-LD types and objects, favicon, heading outline, word count, and an issues list of plain sentences. robots.txt is respected.

Checks the check digit and structure of an identifier with no network call: ISBN-10 and ISBN-13 (with ISBN-10 to 13 conversion), EAN-8, UPC-A, EAN-13 and GTIN-14 (with the GS1 prefix country), VIN (manufacturer code, region, model year), IMEI, ISIN (country) and a generic Luhn number. type=auto detects the type. Up to 50 comma-separated values give a results array.

A Wikipedia page summary by title or search words, in any language: title, short description, summary, page URL, thumbnail and Wikidata ID. For organisations, people and places, Wikidata facts: official website, inception, country, headquarters, date of birth and coordinates. Text is CC BY-SA 4.0 with attribution. Not found returns search suggestions.

Read one web page as clean Markdown (or plain text) for an LLM: the main content without menus, cookie banners and footers, plus title, description, author, published date, language and canonical URL; links on request. robots.txt is respected (a disallowed page is refused and not charged). No JavaScript is run.

All URLs a website lists in its XML sitemaps (from robots.txt, /sitemap.xml or /sitemap_index.xml, following indexes), with lastmod, newest first. Filter by path prefix and changed-since date. For agents that need a site's page list before reading pages.

The great-circle distance between two points in km and miles, the initial bearing and the midpoint. Each point is a lat,lon pair or a place name (geocoded with OpenStreetMap data, ODbL). Straight-line distance only, not a route.

US federal bills from Congress.gov (Library of Congress). Keyword search (q) runs over the 250 most recently updated bills of a Congress, since the API has no full-text search; each match gets its sponsor, status and latest action. A bill number (bill=hr1234-119) returns its cosponsor count, committees and up to 30 actions. Public domain.

Solana wallet holdings: SOL and every SPL / Token-2022 balance with name, symbol, USD price and value (Jupiter), sorted by value, plus the total in USD. Dust and unpriced tokens hidden unless includeDust=1. Information only.

EU VAT number check: format and checksum are tested locally first (a malformed number is rejected with HTTP 400 and no charge), then the official VIES service answers whether it is valid, with the registered name and address where the member state discloses them. All 27 EU states plus Northern Ireland (XI). VIES can take 6-25 seconds when a member state's register is slow; if it does not answer wi

The Crypto Fear & Greed Index today and for the previous days (up to 30), with its classification (extreme fear to extreme greed). Attribution: alternative.me. Information only, not financial advice.

Whether a site publishes /llms.txt and /llms-full.txt: the parsed llms.txt (title, summary, sections with their links) and the size of llms-full.txt. Reads the site itself, through the same URL guard and size cap as the page tools.

US healthcare providers from the NPPES NPI Registry: look up one by its 10-digit NPI (check digit verified) or search by name with an optional state. Each provider gives type, name, credential, status, primary taxonomy and practice address. Information only, not medical advice.

Identifiers and secrets from the Web Crypto random source: UUID v4 and v7, ULID, nanoid (size and alphabet), random passwords (length and character classes) and passphrases (words from the EFF large wordlist, CC BY 3.0 US), up to 100 per call. mode=parse validates a UUID or ULID and reports its version, variant and the time embedded in v1, v6, v7 and ULID. Nothing is stored.

Stablecoins tracked by DefiLlama: circulating supply, peg type and mechanism, price, and the chains each one runs on. With symbol, that coin; without it the 50 largest. Attribution: Data: DefiLlama. Information only, not financial advice.

Current disaster alerts from GDACS (UN OCHA and EC JRC): type (earthquake, tropical cyclone, flood, volcano, drought, wildfire), name, country, alert level, start date, severity and link. Filter by type and alert level. Attribution: GDACS.

A DOI's bibliographic record from Crossref (title, authors, journal, publisher, date, type, citation count, license), or the best matches for a citation-style search (max 10). An unknown DOI answers 404, not charged.

Recent earthquakes from USGS, newest first: magnitude, place, time, depth, coordinates, tsunami flag and alert level. Filter by minimum magnitude, days back (max 30) and a radius around a point. Public domain data.

ENS on Ethereum mainnet. A name (vitalik.eth) resolves to its address, and an address resolves to its primary name, accepted only when that name resolves back to the same address. Returns the avatar and the url, com.twitter, com.github, description and email text records when set. A name that is not registered returns 200 with address null.

An EVM block by number, or the latest one: hash, time, transaction count, gas used and limit, and base fee in gwei. Read over public RPC.

Items of an RSS, Atom or RDF feed, or of the feed a web page advertises: title, link, published date, author and a 300-character summary, newest first (max 50). since keeps items published on or after a date.

Recommended Bitcoin fees in sat/vB (fastest, 30 minutes, 1 hour, economy, minimum), the mempool's size and count, and what a typical 140 vB transaction costs in BTC and USD. Source: mempool.space; USD from Coinbase spot. Cached 30 seconds. Information only, not financial advice.

arXiv papers matching search terms, optionally in one category (cs.AI, math.CO), newest first, max 25: id, title, authors, dates, a 500-character summary, categories and the PDF link. Attribution: Thank you to arXiv for use of its open access interoperability.

Explains a cron expression in plain English and lists its next runs in UTC and in a time zone. Five fields (minute hour day month weekday), or six with seconds first. Names (MON, JAN) and steps are supported. Computed in the Worker; no network call.