Reference data for a blockchain by its chainId: name, gas/native token, block explorers, number of public RPCs and website. Utility for multi-chain agents. Live from chainid.network (ethereum-lists, open data).

Encode a contract function call (calldata) from its signature and arguments, e.g. transfer(address,uint256) with [to, amount]: selector and hex data ready to sign or simulate.

BIC/SWIFT code validation and parsing: bank, country, location and branch codes, test-code flag.

Swap quote and best DEX price on Base: live quotes from Uniswap v3 (all fee tiers) and Aerodrome (stable/volatile) for any ERC-20 pair, ranked best first, with a low-liquidity flag. ETH, USDC, cbBTC, DAI or any token address. Read-only, no swap executed.

Decode EVM calldata (transaction input) with the function signature you provide, checking that it matches the selector, or decode return data with its output types (e.g. uint256,address). Local calculation, no third-party signature databases.

Country profile: name, ISO codes, capital and its coordinates, region, income level, phone prefix, time zones and latest population and GDP per capita. World Bank and libphonenumber data.

Search scientific papers on arXiv (AI, physics, maths, economics...): title, authors, abstract, categories, dates and PDF link; by relevance or newest, with category filter (cs.AI, cs.CR, q-fin...).

Convert a color between HEX, RGB, HSL, HSV and CMYK and, given a background, compute the WCAG 2.x contrast ratio with AA/AAA pass flags; without background, suggests black or white text.

Validate a 5-field cron expression (ranges, steps, names, @daily aliases), explain it in plain English and list its next run times in any time zone, DST-aware.

Latest press releases from central banks and financial regulators (Federal Reserve, ECB, SEC, CFTC, ESMA) in one feed by date, with title, link and summary as published; filter by source or keyword (rate, crypto, stablecoin...).

Company lookup in 10 official European registers plus GLEIF (KYB). Use when you need to verify that a company exists and is active: official registers GLEIF (worldwide, incl. Dutch LEI holders), UK Companies House, Ireland CRO, Estonia, France SIRENE, Norway, Finland, Czechia, Slovakia and Poland (with bank accounts). Returns legal name, status, registry id, legal form, address, founding date and parent companies (GLEIF). Search by name or id.

Business Frameworks · business-frameworks/growth/why@1.2 — why growth is conditional on earning more than r, and where its ceiling is. Call before using the forecast and self-financeable nodes, the $25–50M scale band or the three growth decisions (pace, price, adjacency); returns 298 tokens of original synthesis citing three published works, with child handles — free layer at /catalogue.

Convert APR to APY or APY to APR for any compounding frequency (continuous, daily, hourly, per block...) and optionally project the final value and gain of a deposit over N days. Useful to compare DeFi yields.

Convert coordinates between decimal degrees, degrees-minutes-seconds (40°25'00"N), UTM (zone, easting, northing) and geohash, in any direction, plus a map link.

US dollar reference rates from the Federal Reserve Bank of New York: effective fed funds rate (EFFR) with the Fed's target range, SOFR with 30/90/180-day averages, OBFR, TGCR and BGCR, with volumes and percentiles.

Validate EAN-8, EAN-13, UPC-A, GTIN-14, ISBN-10 and ISBN-13: check digit (and the expected one if wrong), code type, GS1 prefix and registering country, plus ISBN-10/13 conversion.

Convert an amount between the main cryptocurrencies and ECB currencies (0.5 BTC to ETH, 100 USDT to EUR, 1000 EUR to SOL) with alternative.me prices (~190 largest coins) and ECB reference rates.

Find airports by IATA/ICAO code, name or city, or the nearest to coordinates: name, codes, city, country, coordinates, elevation and scheduled service. OurAirports open data.

Great-circle distance between two airports by IATA or ICAO code in km, miles and nautical miles, bearing, approximate flight time and estimated economy-class CO2 per passenger.

Business days in 150+ countries and their regions: count between two dates, or the date after adding N business days, skipping weekends and official holidays, listing the holidays in the range.