"Resources or services available for free" matching MCP connectors:

DNS and email security scanner with 80 MCP tools for SPF, DMARC, DNSSEC, SSL, and brand audits.

Domain attribution and correlation for AI agents, with confidence and per-signal evidence.

Custom domains API for SaaS: connect, verify, and manage customer domains, SSL, and DNS

MCP server for DNSimple — domains, DNS zone records, availability, pricing and contacts.

Domain intel for AI agents: RDAP registration, DNS, email deliverability, tech stack.

Internet identity for AI agents: register or broker domains, email, DNS - pay by card or USDC.

Check email deliverability for a domain: MX, SPF, DKIM, DMARC, blacklists. Graded, no key.

DMCA takedown & host reveal for AI agents: who hosts an infringing URL, even behind Cloudflare.

Scan the open TCP ports of your own public IP. Fast (32) or deep (65535). No key, no signup.

IPInfo MCP — wraps ipinfo.io (free tier, no auth required for basic usage)

IP Lookup MCP — ip-api.com (free, no auth for basic usage)

ipify: caller IPv4/IPv6 echo. Useful for verifying gateway egress.

SIP/VoIP/telecom grounding for AI agents: vendor docs, RFCs, STIR/SHAKEN, traces, configs.

OpenCellID MCP — cell tower geolocation database (free with key)

GreyNoise Community MCP — internet scanner classification (free tier with key)

WHOIS, DNS, SSL, IP geo for security forensics and OSINT — separate from SEO.

Domain registration for AI agents via Stripe or x402 crypto with Cloudflare DNS.

Hosted MCP gateway for Web3 infra discovery across 20+ networks via one endpoint.

Public MCP server for summaries, DNS lookup, catalog, replies, and JSON checks.

The internet's largest queryable infrastructure graph — 7.39 billion nodes, 39 billion edges, 5.6 million threat-intelligence relationships. Pivot from any IP, domain, or ASN across DNS, BGP, WHOIS, GeoIP, and threat intel in a single Cypher query. Most threat-intel and OSINT APIs are point lookups: you ask about one indicator, you get one record. Investigations don't work that way — you start from one suspicious domain and need to trace its hosting, its sibling domains, its registrar, its email