Open Source W3OS Tool

Skill Warden

Static security analyzer for AI skills

Catch supply chain attacks, jailbreak attempts, secret exfiltration payloads, and prompt injection before you install or run AI agent skills.

Get Started

Open source and free, add it to your workflow in minutes.

View on GitHub Get GitHub Action
github.com/W3OSC/skill-warden
Part of the W3OS ecosystem

What's included

  • Prompt Injection: Detects instructions that override AI system context before skills are installed or executed.
  • Jailbreak & Exfiltration: Catches content removing safety constraints and references to SSH keys, cloud credentials, and wallets.
  • Token Smuggling: Flags LLM control tokens injected into skill content that can manipulate model behavior.
  • Obfuscation Detection: Surfaces zero-width characters, homoglyphs, and base64 blobs used to hide malicious payloads.

Architecture

How Skill Warden analyzes AI skills for prompt injection and unsafe behavior.

Skill Warden architecture diagram

Detection categories

Detection Severity Type
Prompt Injection Instructions that override AI system context
Critical Hard fail
Jailbreak Attempt Content removing AI safety constraints
Critical Hard fail
Token Smuggling LLM control tokens injected into skill content
High Hard fail
Secret Grabbing References to SSH keys, cloud credentials, wallets
High Advisory
External Fetch Coercion Instructions pushing the AI to install or download packages
Medium Advisory
Content Obfuscation Zero-width chars, homoglyphs, base64 blobs
Medium Advisory

Protect your skill repo in CI

Add the Skill Warden GitHub Action to your skill repository, it fails CI on any hard violation and uploads findings to the GitHub Security tab via SARIF 2.1.0.

Also available as a CLI: pip install skill-warden

Get it on GitHub Marketplace →
# .github/workflows/skill-warden.yml
name: Warden Security Scan

on:
push:
  branches: [main]
pull_request:

jobs:
scan:
  runs-on: ubuntu-latest
  permissions:
    security-events: write
    contents: read
  steps:
    - uses: actions/checkout@v4
    - uses: W3OSC/skill-warden-action@v1

Secure your AI skill supply chain

Skill Warden is open source and free. Drop it into your CI pipeline in under 5 minutes.

Open source • CI-ready • Part of W3OS