security-baseline

security-baseline is a skill for Claude Code from rampstackco/claude-skills. It costs 103 tokens per session (2,645 once invoked), scanned A, original, MIT.

A checklist for establishing the basic security protections of a website or web app before and after launch. It covers HTTPS, TLS, security headers, content security policy, secrets, and related setup.

In plain words
What is it for?
Use it for pre-launch reviews, new environment setup, periodic audits, vendor onboarding, and hardening after a security incident or finding.
Why use it?
It helps teams find missing protections across the site, hosting environment, third-party scripts, and integrations. This creates a minimum security baseline before public use.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the rampstack-skills plugin — 103 skills shipped together

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.

agentmods
npx agentmods add skills/rampstackco/claude-skills/security-baseline
Any agent
npx skills add rampstackco/claude-skills --skill security-baseline
Clone the repo
git clone --depth 1 https://github.com/rampstackco/claude-skills

Made for: Claude Code.

Or install rampstack-skills, the plugin that ships this one along with the rest of its 103 skills.

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.

agentmods badge for security-baseline

README.md
[![agentmods](https://agentmods.dev/badge/skills/rampstackco/claude-skills/security-baseline.svg)](https://agentmods.dev/skills/rampstackco/claude-skills/security-baseline)
Your own site
<a href="https://agentmods.dev/skills/rampstackco/claude-skills/security-baseline"><img src="https://agentmods.dev/badge/skills/rampstackco/claude-skills/security-baseline.svg" alt="Measured on agentmods" height="20"></a>
Per session 103 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,645 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00103 $0.02645
Opus 5 $0.00051 $0.01323
Sonnet 5 $0.00021 $0.00529
Haiku 4.5 $0.00010 $0.00265

Measured 2d ago against content hash 9fb2c8030710, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

security-baseline 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 2d 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/security-baseline/SKILL.md · 303 lines

How it starts

The opening of the file, as written. The whole thing — 303 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Security Baseline

Establish the security floor for any production website or web app. Stack-agnostic. Covers the things that should be in place before public launch and verified periodically after.


When to use

  • Pre-launch security review
  • Setting up a new site or environment
  • Periodic security audit (quarterly recommended)
  • Onboarding a new vendor or third-party integration
  • Responding to a security finding or report
  • Hardening after an incident

When NOT to use

  • Active incident response (use incident-response)
  • Code-level security review (use code-review-web)
  • Email-specific authentication (SPF/DKIM/DMARC) (use email-deliverability)
  • DNS-level security (CAA, DNSSEC) (use domain-strategy)
  • Performance-related security (DDoS protection sizing) (use performance-optimization)

Required inputs

  • The site or app in scope (URLs, environments)
  • The hosting platform and CDN
  • Authentication method (if any)
  • Third-party scripts and integrations
  • Compliance context (PCI, SOC2, GDPR, etc., if applicable)
  • Existing security tooling

The framework: 6 layers

Security is layered. Each layer addresses a different attack surface.

Layer 1: Transport security

How data moves from server to client.

  • HTTPS everywhere. No HTTP variants serving content.
  • TLS 1.2 minimum, TLS 1.3 preferred. Disable TLS 1.0 and 1.1.
  • HSTS (Strict-Transport-Security) header set, with includeSubDomains and preload for high-confidence sites.
  • Strong cipher suites only. Modern browsers handle this if you pick a modern config from your provider.
  • Certificates from a trusted CA, monitored for expiration.

Layer 2: Response headers

What the browser is told about your site.

Header Purpose Default value
Strict-Transport-Security Force HTTPS max-age=31536000; includeSubDomains
Content-Security-Policy Restrict resource loading Site-specific
X-Content-Type-Options Prevent MIME sniffing nosniff
X-Frame-Options Clickjacking protection DENY or SAMEORIGIN
Referrer-Policy Control referrer info strict-origin-when-cross-origin
Permissions-Policy Control browser features Site-specific (camera, mic, etc.)
Cross-Origin-Opener-Policy Process isolation same-origin (where compatible)
Cross-Origin-Embedder-Policy Cross-origin restrictions require-corp (where applicable)

Read the full file on GitHub · 303 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 303 lines · 103 tokens per session scan A 9fb2c8030710

Subscribe to this mod's changes

security-baseline is a skill published in the GitHub repository rampstackco/claude-skills (817 stars, last pushed 8d ago), licensed MIT. It adds 103 tokens to every session and 2,645 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.