SC
Site Check
🔵 Stable🕐 updated 2026-07-18
🔷 SkillSpec L3
pm-live
Answer 'is this site down or is it just me' properly — curl status/timing diagnostics, DNS cross-check, and TLS certificate reads, assembled into a where-it's-broken diagnosis. Use when asked is this website down, why can't I reach this site, check if my site is up, or is the SSL certificate expired. Produces the layered diagnosis (DNS → TLS → HTTP → content), response timing, cert expiry, and the rerunnable commands.
What to give it
▸The URL / domain — as the user experiences it (scheme and path matter; `example.com` up and `example.com/app` down is a real and common state)
▸The symptom — error message, spinner, cert warning — it picks which layer to check first
▸Whose site — theirs (deeper diagnostics welcome) vs. someone else's (status check, politely)
✅ The bar it holds itself to
Every skill in this library self-verifies — these are this skill's own quality checks, straight from its definition.
✓The verdict names the failing layer, not just up/down
✓Status codes are interpreted (4xx up-but-refusing vs 5xx up-but-broken vs 000 never-connected)
✓Cert answers quote the expiry date with the countdown
✓Connection failures trigger the DNS cross-check before any verdict
✓The one-vantage-point caveat appears
⚠️ What it refuses to do
Do not answer up/down without the layer — the layer is the diagnosis
Do not declare a site dead from one failed local check — run the just-you branch
Do not confuse 403/401 with down — refusing you is a form of up
Do not hammer a struggling site — one clean check per layer, not a retry loop against someone's outage
Do not extend into probing others' infrastructure — status and reachability, not scanning
Install
npx pm-claude-skills add --agent claude # or codex · cursor · gemini · hermes
# or one-line MCP (every skill, any client):
claude mcp add pm-skills -- npx -y pm-claude-skills-mcpRelated skills
🔌 Embed this skill
Drop this on your blog, docs, or site — it renders a "Run this skill" card:
<div data-pm-skill="site-check"></div>
<script src="https://mohitagw15856.github.io/pm-claude-skills/embed.js" async></script>💬 Discussion
Site Check is one of 750 open-source professional AI agent skills — all SkillSpec L3.
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