Domain Monitor MCP Server

MCP (Model Context Protocol) server for domain monitoring. Check WHOIS registration expiry via RDAP and SSL/TLS certificate expiry via crt.sh Certificate Transparency logs — zero API keys, zero signup required.

Why

SSL certificates expire silently and take down production services. WHOIS registration expiry can lose your domain. This MCP server lets AI assistants (Claude Desktop, Claude Code, Cursor, Windsurf) proactively check domain health before it becomes an incident — no external monitoring dashboard needed, just ask your AI.

Tools

`domain_check` — Check Single Domain

Check WHOIS registration expiry and SSL/TLS certificate expiry for one domain. Fetches WHOIS data via RDAP (free, no auth) and SSL data from crt.sh Certificate Transparency logs (free, no auth). URLs with protocols are auto-normalized (e.g., `https://www.example.com/path` → `example.com`).

Input (`domain_check`):

Returns: JSON object with:

• `domain` (string): Normalized domain name
• `whoisExpiry` (string | null): WHOIS registration expiration date (ISO 8601)
• `whoisDaysLeft` (number | null): Days until expiry (negative = expired)
• `sslExpiry` (string | null): SSL/TLS certificate expiration date (ISO 8601)
• `sslDaysLeft` (number | null): Days until SSL expiry (negative = expired)
• `sslIssuer` (string | null): Certificate issuer organization name

LLM prompting hints: Use when the user asks a targeted question about one domain — "is example.com expired?", "check github.com SSL", "when does my domain expire?". Prefer `domain_check` over `domain_check_batch` when checking ≤3 domains for readability.

`domain_check_batch` — Check Multiple Domains

Check multiple domains in parallel (up to 50) with configurable warning thresholds. Each domain returns a severity classification. Returns a summary with counts by status plus per-domain details.

Input (`domain_check_batch`):

Severity classification (per domain):

Returns: JSON object with `total`, `ok`, `warning`, `critical`, `expired`, `error` counts plus `results` array (each with `domain`, `status`, `whoisExpiry`, `whoisDaysLeft`, `sslExpiry`, `sslDaysLeft`, `sslIssuer`, `error`).

LLM prompting hints: Use for portfolio-wide health checks — "check all our domains", "find any domains expiring soon", "audit SSL certs across the company". Adjust `whoisWarnDays` and `sslWarnDays` based on user's renewal workflow (e.g., use `sslWarnDays=30` for enterprises with slow certificate renewal processes).

## Usage

### Claude Code

claude mcp add domain-monitor -- npx domain-monitor-mcp-server

### Claude Desktop

{

"mcpServers": {

"domain-monitor": {

"command": "npx",

"args": ["domain-monitor-mcp-server"]

}

}

}

### Manual

npx domain-monitor-mcp-server

## Data Sources

| Source | Protocol | Rate Limit | API Key |
|--------|----------|------------|---------|
| [rdap.org](https://rdap.org) | RDAP (WHOIS successor) | None documented | None |
| [crt.sh](https://crt.sh) | Certificate Transparency | ~10 req/s | None |

## Install

npm install -g domain-monitor-mcp-server

## Related

- **[Domain Expiry GitHub Action](https://github.com/iPythoning/domain-expiry-action)** — Automated domain expiry monitoring as a CI workflow. Runs on schedule, checks domains, opens GitHub Issues on warnings. Zero config, zero API keys.
- **[Domain Monitor Client](https://github.com/iPythoning/domain-monitor-client)** — Web dashboard for domain monitoring. Visual overview of all your domains' health status. Export to CSV.

## Development

npm install

npm run dev # Watch mode

npm run build # Production build

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