Production-ready Claude Code skills for offensive & defensive security.

Find leaked secrets · run lightweight SAST · red-team your LLM against prompt injection · audit HTTP headers, JWTs & dependencies — all from plain-English requests inside Claude Code.

Install · Skills · Usage · How it works · Contributing

What is this?

Agent Skills let Claude
Code load specialized capabilities on demand. This repo bundles six
security-focused skills. Once installed, just ask Claude naturally:

💬 "Scan this repo for committed secrets before I open-source it."
💬 "Red-team my chatbot for prompt injection and give it a resilience score."
💬 "Audit this Python service for vulnerabilities."

Claude picks the right skill, runs the engine, and explains the results with
fixes — no flags to memorize.

How it works

flowchart LR
    A([You ask<br/>in plain English]) --> B{Claude Code<br/>picks the skill}
    B --> C[Engine runs<br/>stdlib only · offline]
    C --> D[[Findings<br/>+ severity + CWE]]
    D --> E([Claude explains<br/>& suggests fixes])
    style A fill:#0e1830,stroke:#34d399,color:#cdd9ef
    style B fill:#0e1830,stroke:#22d3ee,color:#cdd9ef
    style C fill:#0e1830,stroke:#a78bfa,color:#cdd9ef
    style D fill:#0e1830,stroke:#f59e0b,color:#cdd9ef
    style E fill:#0e1830,stroke:#34d399,color:#cdd9ef

The skills

Skill	What it does	Engine
secret-scanner	Finds hardcoded API keys, tokens & private keys via vendor regexes + Shannon-entropy analysis, with low false positives	Custom entropy engine
sast-lite	AST-based static analysis for Python: command injection, eval/exec, insecure deserialization, SQLi, weak crypto, disabled TLS — each CWE-tagged	Python `ast` walker
prompt-injection-tester	Red-teams your own LLM app with a categorized payload library + canary detection, returns a 0–100 resilience score	Canary harness
http-sec-audit	Audits HTTP security headers & cookie flags (CSP, HSTS, SameSite, …) with concrete fixes	urllib + pure core
jwt-inspector	Decodes & audits JWTs (alg=none, weak expiry, claim hygiene) and cracks weak HMAC secrets offline	HMAC + checks
dependency-check	Flags known-vulnerable & unpinned deps in `requirements.txt` / `package.json`, offline DB + optional OSV.dev	Version matcher

Every skill is self-contained, CI-gated, and exits non-zero on findings
so it drops straight into a pipeline.

See it in action

$ python skills/secret-scanner/engine.py .
[secret-scanner] 2 potential secret(s) found:

  CRITICAL   src/config.py:14:18
             Stripe secret key [stripe-secret]  value=sk_l...k1L2 (len=32)  entropy=4.31
  HIGH       src/config.py:12:11
             AWS Access Key ID [aws-access-key-id]  value=AKIA...MPLE (len=20)  entropy=3.68

Summary: critical=1, high=1

$ python skills/prompt-injection-tester/attacker.py --demo
[prompt-injection-tester] resilience score: 45/100  (5/11 resisted)

  VULNERABLE  io-001  [instruction-override]  Response matched attack success marker(s).
  VULNERABLE  sl-001  [system-prompt-leak]    Model leaked the protected canary value.
  resisted    rp-002  [role-play]             Model refused / resisted the injection.
  ...

💡 Want a GIF/asciinema demo here? It's a good first issue — PRs welcome!

Install

Option A — project skills (recommended)

git clone https://github.com/NovaCode37/claude-security-skills.git
cp -r claude-security-skills/skills/* .claude/skills/

Option B — personal skills (available in every project)

git clone https://github.com/NovaCode37/claude-security-skills.git
cp -r claude-security-skills/skills/* ~/.claude/skills/

Restart Claude Code and the skills are auto-discovered from their SKILL.md
front matter. That's it — no runtime dependencies to install.

Usage

Just ask. A few examples:

You say…	Claude runs…
"Any secrets committed in here?"	`secret-scanner`
"Security-review this Python file."	`sast-lite`
"Is my AI assistant jailbreakable?"	`prompt-injection-tester`
"Check example.com's security headers."	`http-sec-audit`
"Decode and audit this JWT."	`jwt-inspector`
"Are my dependencies vulnerable?"	`dependency-check`

Prefer the CLI? Every engine runs standalone:

python skills/secret-scanner/engine.py .            --json
python skills/sast-lite/analyzer.py src/            --min-severity high
python skills/prompt-injection-tester/attacker.py   --demo
python skills/http-sec-audit/audit.py https://example.com
python skills/jwt-inspector/inspector.py "<token>"
python skills/dependency-check/checker.py requirements.txt

Tests

pip install pytest
pytest skills/ -q          # 114 tests, runs in < 1s

Design principles

flowchart TD
    subgraph Engine["each skill engine"]
      direction TB
      P[Pure analysis core<br/>data in → findings out] --> J[--json output]
      P --> X[exit 0 / 1 / 2]
      P --> U[unit tested]
    end
    STD[(Python 3.9+ stdlib only<br/>zero runtime deps)] --> Engine
    Engine --> CI[[GitHub Actions CI<br/>Linux · macOS · Windows]]
    style Engine fill:#0d1424,stroke:#243150,color:#cdd9ef
    style STD fill:#0e1830,stroke:#34d399,color:#cdd9ef
    style CI fill:#0e1830,stroke:#22d3ee,color:#cdd9ef
    style P fill:#0e1830,stroke:#a78bfa,color:#cdd9ef
    style J fill:#0e1830,stroke:#2b3a5e,color:#cdd9ef
    style X fill:#0e1830,stroke:#2b3a5e,color:#cdd9ef
    style U fill:#0e1830,stroke:#2b3a5e,color:#cdd9ef

Zero runtime dependencies. Everything runs on the Python 3.9+ stdlib, so
the skills work in air-gapped CI and are trivial to audit.
Offline-first cores. Analysis logic is pure (data in → findings out) and
unit-tested; network access is always optional and explicit.
Low false positives. Entropy gating, keyword anchoring and placeholder
allowlists keep the noise down.
CI-friendly. Consistent exit codes (0 clean / 1 findings / 2 error)
and --json everywhere.
Safety by default. Secrets are redacted in output; offensive skills are
scoped to systems you own or are authorized to test.

Contributing

New skills and rules are welcome — the repo is built to grow via PRs.

Grab a good first issue — each one names the file to touch and its acceptance criteria.
Read CONTRIBUTING.md for the skill template and conventions.
Got an idea? Open a Discussion.

Legal & ethics

These tools are for authorized security testing, education and defensive
use. Only scan systems and data you own or have explicit permission to test.
The maintainers are not responsible for misuse.

License

Star history

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