Best Security Skills for Claude Code (2026)

Adding auth, payments, or file uploads to an AI-coded app is where most security bugs sneak in. These six Claude Code security skills automate the review so a coding agent catches the gaps before you ship. See the full ranked list on our best security skills page.

Key takeaways

• The most-installed security skill for Claude Code is firebase-security-rules-auditor with 45,920 installs and 345 GitHub stars (skills.sh registry, GitHub).
• For non-Firebase stacks, security-review brings 210,332 GitHub stars behind a structured FAIL/PASS auth-and-secrets pass (skills.sh registry, GitHub).
• Before installing third-party packages, skill-vetter runs a manual-first checklist and has 19,443 installs (skills.sh registry, GitHub).
• Skillselion tracks 1,294 skills tagged to the ship/security subphase out of 14,013 total skills in the catalog — browse them all under the security category.
• Auth-specific hardening lives in better-auth-security-best-practices at 16,120 installs and 196 stars (skills.sh registry, GitHub).

What is the best security skill for Claude Code?

The best security skill for Claude Code is firebase-security-rules-auditor, with 45,920 installs and 345 GitHub stars (skills.sh registry, GitHub). It red-teams your Firestore security rules after every edit, catching update bypasses and authority-spoofing bugs before they reach production — the single most common class of mistake in AI-generated Firebase apps.

Install it from its repo firebase/agent-skills.

If you are not on Firebase, two alternatives lead: security-review by affaan-m (10,312 installs, skills.sh registry, GitHub) runs a structured FAIL/PASS pass whenever you touch auth, APIs, secrets, uploads, or payments; and security-requirement-extraction by wshobson (14,107 installs, skills.sh registry, GitHub) turns specs into structured security requirements before you write code. Compare all of them on the best security skills pillar.

Which security skill should I use for authentication?

For authentication, use better-auth-security-best-practices, which has 16,120 installs and 196 GitHub stars (skills.sh registry, GitHub). It hardens login and session flows specifically for SaaS and API products built on the Better Auth library, covering the token, cookie, and session pitfalls that generic reviewers miss.

If your auth runs on Firebase instead, the same firebase-security-rules-auditor (45,920 installs, skills.sh registry, GitHub) validates the rules that gate every authenticated read and write. Map the right pick to your stack on the dev-tools category page.

How do I vet a skill before installing it?

Run skill-vetter first — it has 19,443 installs and 62 GitHub stars (skills.sh registry, GitHub) and applies a conservative, manual-first security checklist to any SKILL.md package before you install it from ClawHub, GitHub, or a shared file. Because skills execute with your agent's permissions, vetting untrusted packages is non-negotiable; the OWASP Top 10 maps directly to the injection and supply-chain risks it screens for.

With 1,019 marketplaces and 2,385 plugins in the Skillselion catalog, supply-chain hygiene matters more every week. A faster sibling, firestore-security-rules-auditor (20,281 installs, skills.sh registry, GitHub), targets the same create/update gaps and authority-spoofing paths specifically for Firestore — use whichever matches your data layer.

Which security skill turns specs into requirements?

Use security-requirement-extraction, with 14,107 installs and 36,507 GitHub stars (skills.sh registry, GitHub). It converts product specs and compliance goals into structured security requirements — domains, priorities, and acceptance criteria — before any code exists, which is the cheapest point to catch a design-level flaw. Backed by 36,507 GitHub stars (skills.sh registry, GitHub), it is among the most-starred security skills in the catalog. Pair it with the OWASP Cheat Sheet Series for concrete control implementations, then run a final pass with security-review's FAIL/PASS patterns before merge.

A complete starter stack

1. security-requirement-extraction — define security requirements before coding (14,107 installs). 2. skill-vetter — vet every third-party skill before install (19,443 installs). 3. firebase-security-rules-auditor — red-team your data-access rules (45,920 installs). 4. better-auth-security-best-practices — harden auth and sessions (16,120 installs). 5. security-review — final FAIL/PASS pass before you ship (210,332 stars).

Common pitfalls

• Running a security review only at the end. Extract requirements up front; a flaw baked into the data model is far costlier to fix after launch.
• Installing skills without vetting them. Skills run with agent permissions — skip skill-vetter and you invite supply-chain risk.
• Trusting client-side checks. Firestore and API rules are the real gate; the rules auditors exist because client validation is trivially bypassed.

Start with the requirement-extraction step, then layer the auditors and the final review — and browse every option on our security skills directory.

Common questions