CertGuard MCP Server

by workers-mike-tusa-certguard Your server? Claim it

answering

CertGuard is answering right now. Last checked 14 min ago. It exposes 1 tools.

Free SSL/TLS certificate checker: expiry, chain trust, hostname match, TLS version, A/B/C/F grade.

Uptime history 32 days of history

32 days agonow

100.0%

Uptime 24h

91 of 91 checks

Tools

read from the server

105 ms

Response time

average over 24h

open, no key

Access

streamable-http

What changed 1

Every tool that appeared, vanished or quietly changed what it asks for. Recorded since 16 October 2026. No other catalogue keeps this.

16 Oct a tool changed version

Nothing serious here today

Today is the operative word: we check CertGuard every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 14 min ago.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add certguard --transport http https://certguard.mike-tusa.workers.dev/mcp

Settings → Connectors → Add custom connector, then paste this address

https://certguard.mike-tusa.workers.dev/mcp

~/.codex/config.toml

[mcp_servers.certguard]
url = "https://certguard.mike-tusa.workers.dev/mcp"

.cursor/mcp.json

{
  "mcpServers": {
    "certguard": {
      "url": "https://certguard.mike-tusa.workers.dev/mcp"
    }
  }
}

.vscode/mcp.json

{
  "servers": {
    "certguard": {
      "type": "http",
      "url": "https://certguard.mike-tusa.workers.dev/mcp"
    }
  }
}

Available tools 1

Read directly from the server with tools/list, grouped by what they act on. If a tool disappears, we record the date.

certificate

check_certificate

Run a live TLS handshake against host:port and audit the certificate the server presents. Returns an A/B/C/F grade and summary, expiry (days remaining), hostname match, chain completeness and trust against Mozilla's root store, negotiated TLS version and cipher suite, key type/size, findings, and a link to the full report. Revocation (OCSP/CRL) is NOT checked. Hosts on Cloudflare's own network cannot be checked live (result: isError with code live_check_unavailable, no grade); a failed handshake returns check_failed with no grade. Read-only: it only opens a TLS connection to the public host. Same engine, cache and limits as the CertGuard JSON API (GET /api/v1/check).

Endpoints

URL	Transport	State	Latency	Checked
https://certguard.mike-tusa.workers.dev/mcp	streamable-http	answering	104 ms	14 min ago

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same job, measured the same way

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Ssl Cert MCP

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Inspect TLS certificates of a host: issuer, expiry, and SAN. No key required.

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Upcheck

by upcheck

Monitor website uptime, SSL certificates, DNS, domain expiry and page changes, and manage alerts.

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RenewRoster

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Track domain and SSL certificate expiry for your agency clients from any MCP client.

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CertGuard — questions

Answers built from our own checks of this server.

What can CertGuard do?

It exposes 1 tools, read directly from the server on our last check. Among them: check_certificate. The full list with descriptions is on this page — we take it from the server itself via tools/list, not from a README. How MCP servers expose tools in the first place →

Is CertGuard working right now?

We send a real MCP handshake every 15 minutes. Over the last 24 hours 91 of 91 checks got a reply (100.0%), average response time 105 ms. The bar chart above shows every period we have measured.

How do I connect CertGuard?

Copy the ready config from this page. We generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each in the form that client actually reads. It is a remote server, so there is nothing to install — the client connects to the address.

Does CertGuard need an API key?

No. CertGuard completed a full MCP handshake with us as an anonymous client and listed its tools without asking for anything. All 1 of them are readable on this page. This is what we observed, not what the docs claim.

How fast is CertGuard?

It answers our handshake in 105 ms on average, which is faster than 92% of all working MCP servers we measure. That puts it in the quick quarter of the ecosystem. The comparison comes from our own checks across the whole registry, every 15 minutes.