Guard Scanner

Security scanner and runtime guard for OpenClaw skills, MCP servers, and AI agent workflows. Detects prompt injection, identity hijacking, memory poisoning, A2A contagion, secret leaks, supply-chain abuse, and dangerous tool calls with 364 static threat patterns across 35 threat categories plus 27 runtime checks. Use when reviewing a new skill before install, scanning a workspace in CI/CD (SARIF/JSON/HTML), auditing npm/GitHub/ClawHub assets for leaked credentials, running watch mode during development, exposing scanner tools over MCP for Cursor/Windsurf/Claude Code/OpenClaw, or enforcing before_tool_call policy in OpenClaw. v16 adds 5-layer analysis output (`layer`, `layer_name`, `owasp_asi`, `protocol_surface`) and `--compliance owasp-asi`. MIT licensed; single runtime dependency (`ws`).

Security scanner and runtime guard for the agentic stack. Use it before installing a skill from ClawHub, when auditing MCP servers or OpenClaw workspaces, when wiring security checks into CI/CD, or when you want OpenClaw to block dangerous tool calls at runtime.

It covers prompt injection, identity hijacking, memory poisoning, A2A contagion, MCP abuse, secret leakage, supply-chain abuse, and dangerous execution patterns. v16 adds a 5-layer analysis pipeline, OWASP ASI projection mode, richer finding metadata, and Rust runtime evidence integration.

Quick Start

# Scan a skill directory
npx -y @guava-parity/guard-scanner ./my-skills/ --verbose

# Scan with identity protection
npx -y @guava-parity/guard-scanner ./skills/ --soul-lock --strict

# Filter to OWASP ASI mapped findings only
npx -y @guava-parity/guard-scanner ./skills/ --compliance owasp-asi --format json

# Installed CLI
guard-scanner ./skills/ --strict

# npm exec compatibility
npm exec --yes --package=@guava-parity/guard-scanner -- guard-scanner ./skills/ --strict

Core Commands

Scan

guard-scanner <dir>         # Scan directory
guard-scanner <dir> -v      # Verbose output
guard-scanner <dir> --json  # JSON report file
guard-scanner <dir> --sarif # SARIF for CI/CD
guard-scanner <dir> --html  # HTML report
guard-scanner <dir> --compliance owasp-asi --format json

Asset Audit

Audit public registries for credential exposure.

guard-scanner audit npm <username>
guard-scanner audit github <username>
guard-scanner audit clawhub <query>
guard-scanner audit all <username> --verbose

MCP Server

Start as MCP server for IDE integration.

guard-scanner serve

Editor config (Cursor, Windsurf, Claude Code, OpenClaw):

{
  "mcpServers": {
    "guard-scanner": {
      "command": "npx",
      "args": ["-y", "@guava-parity/guard-scanner", "serve"]
    }
  }
}

MCP tools: scan_skill, scan_text, check_tool_call, audit_assets, get_stats, and the async experimental task helpers.

Quality Contract

Public quality contract:

• Benchmark corpus version: 2026-03-15.quality-v17
• Precision target: >= 0.90
• Recall target: >= 0.90
• FPR/FNR budgets: <= 0.10
• Explainability completeness: 1.0
• Runtime policy latency budget: 5ms

Evidence surfaces:

• docs/spec/capabilities.json
• docs/data/corpus-metrics.json
• docs/data/benchmark-ledger.json
• docs/data/fp-ledger.json

Watch Mode

Monitor skill directories in real-time during development.

guard-scanner watch ./skills/ --strict --soul-lock

VirusTotal Integration

Combine semantic detection with VirusTotal's 70+ antivirus engines. Optional — guard-scanner works fully without it.

export VT_API_KEY=your-key
guard-scanner scan ./skills/ --vt-scan

Runtime Guard

The validated OpenClaw surface is the compiled runtime plugin entry (dist/openclaw-plugin.mjs) discovered through package.json > openclaw.extensions and mounted on before_tool_call for OpenClaw v2026.3.13, with regression coverage kept on v2026.3.8.

The before_tool_call hook provides 27 runtime checks across 5 defense layers, while v16 scan output adds a second 5-layer analysis view:

Layer	Focus
1. Threat Detection	Reverse shell, curl|bash, SSRF
2. Trust Defense	SOUL.md tampering, memory injection
3. Safety Judge	Prompt injection in tool arguments
4. Behavioral	No-research execution detection
5. Trust Exploitation	Authority claims, creator bypass

Modes: monitor (log only), enforce (block CRITICAL, default), strict (block HIGH+).

v16 Output Surface

• Finding fields: layer, layer_name, owasp_asi, protocol_surface
• Compliance mode: --compliance owasp-asi
• MCP summaries: scan_skill, scan_text, and get_stats now surface layer and ASI context
• Runtime evidence: Rust memory_integrity and soul_hard_gate modules are represented in the TypeScript pipeline

Key Flags

Flag	Effect
--verbose / -v	Detailed findings with line numbers
--strict	Lower detection thresholds
--soul-lock	Enable identity protection patterns
--json / --sarif / --html	Output format
--fail-on-findings	Exit 1 on findings (CI/CD)
--check-deps	Scan package.json dependencies
--rules <file>	Load custom rules JSON
--plugin <file>	Load plugin module
--compliance owasp-asi	Keep only OWASP ASI mapped findings in output

Custom Rules

module.exports = {
  name: 'my-plugin',
  patterns: [
    { id: 'MY_01', cat: 'custom', regex: /dangerous_pattern/g, severity: 'HIGH', desc: 'Description', all: true }
  ]
};

guard-scanner ./skills/ --plugin ./my-plugin.js

CI/CD Integration

# .github/workflows/security.yml
- name: Scan AI skills
  run: npx -y @guava-parity/guard-scanner ./skills/ --format sarif --fail-on-findings > report.sarif
- uses: github/codeql-action/upload-sarif@v3
  with:
    sarif_file: report.sarif

Threat Categories

35 categories covering OWASP LLM Top 10 + Agentic Security Top 10. See src/patterns.ts for the full pattern database. Key categories:

• Prompt Injection — hidden instructions, invisible Unicode, homoglyphs
• Identity Hijacking ⚿ — persona swap, SOUL.md overwrites, memory wipe
• Memory Poisoning ⚿ — crafted conversation injection
• MCP Security — tool poisoning, SSRF, shadow servers
• A2A Contagion — agent-to-agent worm propagation
• Supply Chain V2 — typosquatting, slopsquatting, lifecycle scripts
• CVE Patterns — CVE-2026-2256, 25046, 25253, 25905, 27825

⚿ = Requires --soul-lock flag