ARIN Whois


Slug	`arin-whois`
Category	Data Enrichment
Maturity	Beta
Auth Type	None (public API)

Summary

Read-only MCP integration with the ARIN Whois RESTful API. Lets a Prospector Studio agent enrich IP addresses with registration metadata — owning organization, network range, contact handles — directly from the authoritative North American regional registry.

Capabilities

Look up the ARIN Whois record for an IPv4 or IPv6 address.
Look up an organization record by ARIN handle.
Look up a network record by ARIN handle.

Required Headers

The ARIN Whois RESTful API is public. No authentication headers required.

Allowed Hosts

whois.arin.net

Tools

Tool	Action	Purpose
`lookup_ip`	read	Whois registration record for an IP address.
`lookup_org`	read	Organization details by ARIN handle.
`lookup_net`	read	Network details by ARIN handle.

Invocation Example

{
  "name": "lookup_ip",
  "arguments": {
    "ip": "8.8.8.8"
  }
}

Operational Notes

Authoritative for ARIN region only. ARIN covers North America, parts of the Caribbean, and Antarctica. For addresses delegated to RIPE, APNIC, LACNIC, or AFRINIC the response will redirect to the appropriate RIR — agents should be prepared to follow up against another data source for full coverage.
Public API; rate-limited. ARIN does not require auth but enforces fair-use limits. High-volume bulk enrichment should batch and back off on errors.
Reference docs. ARIN Whois RESTful API.