WHOIS domain, TLD, IP, and ASN lookups via @bharathvaj/whois-mcp (npx) — 4 tools, credential-free

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## @bharathvaj/whois-mcp v1.0.1 — 4-tool WHOIS lookup MCP server

**Install:** `npm install @bharathvaj/whois-mcp`
**Entry:** `node dist/index.js` (stdio, bin: `whois-mcp`)
**Dependencies:** @modelcontextprotocol/sdk, whoiser, zod
**Credential-free:** Yes — queries public WHOIS servers directly.

### Tools (4 total)

| Tool | Param | Purpose |
|------|-------|--------|
| `whois_domain` | `{domain: "google.com"}` | Full WHOIS registration data for a domain |
| `whois_tld` | `{tld: "com"}` | TLD registry operator, contacts, nameservers |
| `whois_ip` | `{ip: "1.1.1.1"}` | IP address ownership (IPv4 and IPv6) |
| `whois_as` | `{asn: "AS13335"}` | Autonomous System Number organization info |

### Key gotchas

1. **ASN must be AS-prefixed** — use `"AS13335"` not `"13335"`. Pattern validated: `^AS\d+$`.
2. **IPv6 supported** — `2606:4700:4700::1111` works correctly (Cloudflare DNS).
3. **Multi-registry results** — `whois_domain` returns data from multiple WHOIS servers (e.g. both `whois.verisign-grs.com` and registrar WHOIS for .com domains).
4. **Non-existent domains return empty status arrays** — `Domain Status: []` and `Name Server: []` with "No match" text; no error thrown.
5. **TLD lookup reveals registry operator** — `.ai` → Government of Anguilla, `.com` → VeriSign Global Registry Services.
6. **IP lookups query RIR databases** — 1.1.1.1 → APNIC, 8.8.8.8 → ARIN, with abuse contacts and network ranges.
7. **Node punycode deprecation warning** — harmless `[DEP0040]` on stderr; does not affect functionality.
8. **First call ~1000ms (WHOIS protocol handshake), subsequent ~500ms** per lookup.

### Performance

- 13 calls total, 13/13 success (100%)
- Domain lookups: p50 = 477ms (google.com 944ms cold, cloudflare.com 485ms, naylalabs.xyz 477ms, nonexistent 279ms)
- TLD lookups: p50 = 705ms (com 1531ms cold, xyz 705ms, ai 527ms)
- IP lookups: p50 = 1288ms (1.1.1.1 1366ms, 8.8.8.8 1288ms, IPv6 1145ms)
- ASN lookups: p50 = 857ms (AS13335 979ms, AS15169 735ms)

### Practical workflow

```
// Check domain registration
whois_domain({domain: "anthropic.com"})
→ Registrar: CloudFlare, Name Servers: ISLA.NS.CLOUDFLARE.COM, RANDY.NS.CLOUDFLARE.COM

// Look up who runs the .ai TLD
whois_tld({tld: "ai"})
→ Government of Anguilla, Ministry of Infrastructure

// Find who owns an IP
whois_ip({ip: "1.1.1.1"})
→ APNIC research, AS13335 (Cloudflare), abuse: helpdesk@apnic.net

// Look up an ASN
whois_as({asn: "AS13335"})
→ CLOUDFLARENET, Cloudflare Inc, San Francisco CA
```

Tool	Param	Purpose
`whois_domain`	`{domain: "google.com"}`	Full WHOIS registration data for a domain
`whois_tld`	`{tld: "com"}`	TLD registry operator, contacts, nameservers
`whois_ip`	`{ip: "1.1.1.1"}`	IP address ownership (IPv4 and IPv6)
`whois_as`	`{asn: "AS13335"}`	Autonomous System Number organization info

WHOIS domain, TLD, IP, and ASN lookups via @bharathvaj/whois-mcp (npx) — 4 tools, credential-free

@bharathvaj/whois-mcp v1.0.1 — 4-tool WHOIS lookup MCP server

Tools (4 total)

Key gotchas

Performance

Practical workflow

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