MCPFax · Public-Data Utility API

31 thin, reliable JSON endpoints over free public & government data. Pay per call with x402 (USDC on Base) — no key, no signup. Also an MCP server.

x402 v1 · scheme exact network base (Base · eip155:8453) asset USDC payTo 0x1831f336585a6C67B6A954d28f3E07F44C4EEBbd $0.001–$0.004 / call

Discovery: /v1/catalog · /llms.txt · /health
Unpaid requests receive a 402 with the payment challenge. Retry with a base64 X-PAYMENT header to receive the data.

Geo & Places

EndpointReturnsUpstreamPrice
GET /v1/geocodePlace name → coordinates, country, timezone.Open-Meteo / Nominatim$0.001try →
GET /v1/reverse-geocodeCoordinates → nearest address.Nominatim / BigDataCloud$0.001try →
GET /v1/timezoneCoordinates → IANA timezone, UTC offset, local time.Open-Meteo$0.001try →
GET /v1/zipZIP/postal code → place(s) & coordinates.Zippopotam.us$0.001try →
GET /v1/airports/nearestCoordinates → nearest airports (IATA/ICAO) by distance.OurAirports (edge dataset)$0.002try →
GET /v1/ip-geolocationIP address → location, ASN, ISP.ipwho.is / ip-api$0.001try →
GET /v1/countryName/ISO code → currency, capital, calling code, languages, flag.ISO 3166 (edge dataset)$0.001try →

Weather & Environment

EndpointReturnsUpstreamPrice
GET /v1/weatherCurrent conditions + multi-day forecast by coordinate or place.Open-Meteo / NWS$0.001try →
GET /v1/weather-alertsActive NWS watches/warnings for a US coordinate.US National Weather Service$0.002try →
GET /v1/air-qualityUS & European AQI plus pollutant concentrations by coordinate.Open-Meteo Air Quality (CAMS)$0.001try →
GET /v1/sunSunrise, sunset, solar noon, day length by coordinate.sunrise-sunset.org / Open-Meteo$0.001try →

Time & Calendar

EndpointReturnsUpstreamPrice
GET /v1/holidaysPublic holidays for a country & year.Nager.Date$0.001try →
GET /v1/business-daysCount business days in a range, or add/subtract N business days, skipping weekends & holidays.computed + Nager.Date$0.001try →

Finance & Markets

EndpointReturnsUpstreamPrice
GET /v1/fxReference FX rates (ECB) with optional amount conversion.Frankfurter (ECB) / open.er-api$0.001try →
GET /v1/crypto-priceSpot price for a crypto asset in a fiat/crypto quote currency.Coinbase / CoinGecko$0.001try →
GET /v1/stock-quoteDelayed quote & key stats for an equity/ETF/index.Yahoo Finance$0.001try →
GET /v1/sec-company-factsCompany profile + recent filings; or XBRL financial facts for a concept.SEC EDGAR$0.003try →
GET /v1/inflationAdjust an amount between years using CPI (any country, not just US).World Bank CPI$0.002try →
GET /v1/econ-indicatorWorld Bank indicator time series for a country (GDP, unemployment, etc.).World Bank Open Data$0.002try →
GET /v1/leiLegal Entity Identifier record by LEI code or entity name.GLEIF$0.002try →

Reference & Registries

EndpointReturnsUpstreamPrice
GET /v1/vin-decodeDecode a US-market Vehicle Identification Number.NHTSA vPIC$0.003try →
GET /v1/icd10Search ICD-10-CM diagnosis codes by term or code.NLM Clinical Tables$0.002try →
GET /v1/naicsOfficial 2022 NAICS code → title, hierarchy, children; or keyword search.U.S. Census 2022 NAICS (edge dataset)$0.002try →
GET /v1/cfrFetch current Code of Federal Regulations text for a citation.eCFR (GovInfo)$0.003try →
GET /v1/drug-labelopenFDA structured drug labeling (uses, warnings, dosage).openFDA$0.003try →
GET /v1/wikipediaLead summary/extract for a Wikipedia page.Wikipedia REST$0.001try →

Utility & Dev

EndpointReturnsUpstreamPrice
GET /v1/unit-convertConvert between units (length, mass, volume, speed, area, data, time, pressure, energy, temperature, angle).deterministic edge compute$0.001try →
GET /v1/dnsResolve DNS records via DNS-over-HTTPS.Google / Cloudflare DoH$0.001try →
GET /v1/rdapStructured domain/IP registration data (modern whois).RDAP (rdap.org)$0.001try →
GET /v1/robotsFetch and parse a site's robots.txt and llms.txt.direct fetch$0.001try →
GET /v1/validate-emailSyntax check + live MX/deliverability + disposable-domain flag.edge compute + DoH$0.001try →

Upstreams are free/public and cited per endpoint. Reference datasets (NAICS, countries, airports) are public-domain and served from the edge for reliability. Data is provided as-is; not for safety-critical or medical use. Contact: 300tsb@gmail.com.