What is certificate-checker?

A checker for SSL/TLS certificates, the security credentials websites use to encrypt connections. It reports certificate dates, identity details, issuer, chain, and validity for a domain and port.

Use it to check a domain's certificate expiry, issuer, subject, certificate chain, and validity, normally on port 443.

It helps detect expired, invalid, or incorrectly configured certificates before they interrupt secure connections. It can also show who issued a certificate and how it links to trusted certificates.

certificate-checker — Skill for Claude Code and Codex by fisker086

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add fisker086/AIOps --skill cert_checker

Clone the repo

git clone --depth 1 https://github.com/fisker086/AIOps

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/fisker086/aiops/cert_checker/github.svg)](https://agentmods.dev/skills/fisker086/aiops/cert_checker)

Your own site

<a href="https://agentmods.dev/skills/fisker086/aiops/cert_checker"><img src="https://agentmods.dev/badge/skills/fisker086/aiops/cert_checker/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/fisker086/aiops/cert_checker"><img src="https://agentmods.dev/badge/skills/fisker086/aiops/cert_checker.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 14 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 125 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin original No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00014	$0.00125
Opus 5.5	$0.00006	$0.00050
Sonnet 5.5	$0.00003	$0.00025
Haiku 4.5	$0.00001	$0.00013

Measured 2mo ago against content hash 255102eb83b7, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

certificate-checker scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/cert_checker/SKILL.md · 21 lines

What it actually says