DEVELOPERS

Ask the atlas

Query HostsAtlas from your code or your AI assistant: who hosts a domain and who registered it, who owns an address or a network, live DNS, certificates and email setup, providers and their footprint, data centers near a place, live incidents, GPU prices, latency estimates, where to host for an audience and submarine cables.

MCP server
https://skycisa.com/mcp
REST API
https://skycisa.com/api/v1
  • No API key
  • JSON over HTTPS
  • Open CORS
  • 120 requests a minute

Connect your assistant

One remote MCP server with eighteen read-only tools. Streamable HTTP, no sign-in.

Claude

  1. Open Settings → Connectors.
  2. Choose Add custom connector.
  3. Name it HostsAtlas and paste this URL:
https://skycisa.com/mcp

Claude Code

Run in your terminal:

claude mcp add --transport http hostsatlas https://skycisa.com/mcp

Cursor & others

Add to ~/.cursor/mcp.json. ChatGPT, VS Code and other MCP clients take the same URL.

{
  "mcpServers": {
    "hostsatlas": {
      "url": "https://skycisa.com/mcp"
    }
  }
}

Tools

What your assistant can ask. Every answer is JSON with links back to the atlas.

  • who_hosts

    Who hosts a domain: host, CDN, platform, DNS and email providers, from live DNS.

    Try: “Who hosts nytimes.com?”

  • search_providers

    Find providers by name, category and country.

    Try: “GPU clouds with servers in Germany”

  • get_provider

    One provider: footprint by country and city, cheapest plans, incidents, certifications.

    Try: “Where does Hetzner have data centers?”

  • find_datacenters

    Data centers by country, city or provider, or nearest to a point.

    Try: “Data centers within 25 km of Frankfurt”

  • live_incidents

    Open incidents and maintenance, as providers' status pages publish them.

    Try: “Is any cloud down right now?”

  • what_changed

    The dated record of the market: price moves, listings, data centers, certifications and incidents.

    Try: “What changed in GPU prices this week?”

  • gpu_prices

    GPU models with market prices, and the cheapest offers for one.

    Try: “Cheapest H100 in the US”

  • estimate_latency

    Round-trip estimate between two points, along measured routes between network hubs.

    Try: “Latency from Singapore to London?”

  • where_to_host

    The best cities to host in for users in a set of countries.

    Try: “Where should I host for the US, Germany and Japan?”

  • submarine_cables

    Submarine cables, their owners and landing points.

    Try: “Which cables land in Portugal?”

  • lookup_domain

    A domain's registration from the registry (RDAP, or whois): registrar, dates, status, name servers; who sells it when it is free.

    Try: “When does github.com expire?”

  • lookup_ip

    Who owns an address: its announced prefix and network, the registry record, reverse DNS, the cloud region, top sites on it.

    Try: “Whose address is 8.8.8.8?”

  • lookup_asn

    A network: prefixes announced in BGP and their RPKI, upstream networks, data centers and exchange points.

    Try: “Who does AS24940 connect through?”

  • lookup_dns

    Live DNS records, CAA and DNSSEC for a name.

    Try: “What are the MX records of proton.me?”

  • lookup_tls

    The certificate a site serves: issuer, expiry, names, chain; TLS version, HTTP/2 and HTTP/3, HSTS.

    Try: “When does the certificate of example.com expire?”

  • lookup_email

    Email setup: mail servers and provider, SPF, DMARC, MTA-STS, TLS reporting, BIMI and DKIM.

    Try: “Is DMARC set up for my-company.com?”

  • lookup_http

    Fetch a URL: every redirect, the final status, compression, caching and security headers.

    Try: “Where does http://github.com redirect?”

  • grade_site

    Grade a domain's infrastructure A+ to F: DNS, TLS, email, headers, IPv6, RPKI, provider concentration — every check with a fix.

    Try: “Grade stripe.com and tell me what to fix first.”

  • is_it_down

    Is a service down right now: our minute checks, its status page read live, visitors' reports and a verdict.

    Try: “Is the OpenAI API down right now?”

REST API

GET requests, JSON answers. Lists take limit (default 20, at most 100). Errors come as {"error": "…"} with a 4xx status.

GET/api/v1/providersSearch hosting, cloud and GPU providers.
Parameters: q, category, country, limit
curl "https://skycisa.com/api/v1/providers?q=hetzner"
GET/api/v1/providers/{slug}One provider: footprint, cities, cheapest plans, incidents, compliance.
curl "https://skycisa.com/api/v1/providers/hetzner"
GET/api/v1/datacentersData centers; nearest first when near is given.
Parameters: country, city, near=lat,lon, radius_km, provider, limit
curl "https://skycisa.com/api/v1/datacenters?near=50.11,8.68&radius_km=25"
GET/api/v1/whohostsWho hosts a domain (live DNS lookup).
Parameters: d
curl "https://skycisa.com/api/v1/whohosts?d=example.com"
GET/api/v1/incidentsLive incidents and maintenance from status pages.
Parameters: status=open|recent|planned|all, provider, limit
curl "https://skycisa.com/api/v1/incidents?status=open"
GET/api/v1/gpusGPU models with the cheapest and median price per GPU-hour.
Parameters: q, vendor, limit
curl "https://skycisa.com/api/v1/gpus"
GET/api/v1/gpus/{slug}/offersThe cheapest active offers for one GPU.
Parameters: country, limit
curl "https://skycisa.com/api/v1/gpus/h100-sxm/offers?country=US&limit=5"
GET/api/v1/latencyRound-trip estimate along measured routes between network hubs.
Parameters: from=lat,lon, to=lat,lon
curl "https://skycisa.com/api/v1/latency?from=52.52,13.40&to=40.71,-74.00"
GET/api/v1/where-to-hostCities ranked for users in these countries.
Parameters: countries
curl "https://skycisa.com/api/v1/where-to-host?countries=US,DE,JP"
GET/api/v1/changesWhat changed, by the day it was recorded.
Parameters: day, before, days, kind, cc, cat, p, limit
curl "https://skycisa.com/api/v1/changes?kind=prices&days=7"
GET/api/v1/cablesSubmarine cables by name, owner, landing station or country.
Parameters: q, country, limit
curl "https://skycisa.com/api/v1/cables?country=PT"
GET/api/v1/cables/{slug}One cable with its landing points.
curl "https://skycisa.com/api/v1/cables/ellalink"
GET/api/v1/domainA domain's registration from the registry (RDAP, or whois when there is none).
Parameters: d
curl "https://skycisa.com/api/v1/domain?d=example.com"
GET/api/v1/ipWho owns an address: prefix, network, registry record, reverse DNS, cloud region.
Parameters: ip
curl "https://skycisa.com/api/v1/ip?ip=1.1.1.1"
GET/api/v1/asnA network: announced prefixes, RPKI, upstreams, data centers and exchange points.
Parameters: asn
curl "https://skycisa.com/api/v1/asn?asn=AS13335"
GET/api/v1/dnsLive DNS: A, AAAA, HTTPS, NS, SOA, MX, TXT, CAA, DS, DNSKEY.
Parameters: d
curl "https://skycisa.com/api/v1/dns?d=example.com"
GET/api/v1/tlsThe certificate and chain a site serves, TLS version, HTTP/2 and HTTP/3, HSTS.
Parameters: d
curl "https://skycisa.com/api/v1/tls?d=example.com"
GET/api/v1/mailEmail setup: MX, SPF, DMARC, MTA-STS, TLS-RPT, BIMI; DKIM at a selector.
Parameters: d, dkim
curl "https://skycisa.com/api/v1/mail?d=gmail.com&dkim=20230601"
GET/api/v1/httpAn HTTP fetch: each redirect, final status, caching and security headers.
Parameters: url
curl "https://skycisa.com/api/v1/http?url=http://example.com"
GET/api/v1/gradeA domain's infrastructure report card: grade A+ to F, score, category scores, every check with evidence and a fix.
Parameters: d
curl "https://skycisa.com/api/v1/grade?d=github.com"
GET/api/v1/downIs it down: a service's minute checks, status page, reports and verdict; every watched service without service.
Parameters: service
curl "https://skycisa.com/api/v1/down?service=openai"

Limits

  • No API key and no sign-up.
  • 120 requests a minute per IP for /api/v1 and for /mcp; live lookups (who hosts, domain, IP, DNS, TLS, email, HTTP) 20 a minute each, networks and report cards 10.
  • Answers are cached for a few minutes. Status pages are read every hour, prices every six hours.
  • Latency and where-to-host figures are estimates (round trips measured between network hubs, plus distance at each end), not measurements of your own route.
  • Prices are list prices in USD and can lag the provider's own site.

Data & attribution

The atlas combines open datasets. When you publish results, credit HostsAtlas with a link, and keep the OpenStreetMap credit for data centers and cables that come from it.

PeeringDB
Data centers, networks, exchanges
PeeringDB AUP, attribution
OpenStreetMap
Data centers, submarine cables
© OpenStreetMap contributors, ODbL 1.0
Wikidata · GeoNames
Cable details, places
CC0 · CC BY 4.0
Chrome UX Report
Top sites behind who-hosts reach
CC BY 4.0
iptoasn · bgp.tools
Address-to-network map, network tags
PDDL · attribution
FedRAMP · ANSSI
Verified certifications
US public domain · ANSSI, attribution
SkyPilot catalogs
Cloud and GPU prices
Apache-2.0
Status pages
Incidents and maintenance
Each provider's published feed
Globalping
Live probes on the globe (the API's latency is an estimate)
Probes by Globalping
Cloudflare Radar
Internet outages, traffic drops and route hijacks on Is it down?
CC BY-NC 4.0