security-check

security-check is a command for coding agents from FlorianBruniaux/claude-code-plugins. It costs 11 tokens per session (1,658 once invoked), scanned B, original, MIT.

A quick check of Claude Code configuration against a database of known threats, vulnerable MCP servers, and suspicious patterns.

In plain words
What is it for?
It is for reviewing MCP settings, hooks, agents, and configuration files for known security threats.
Why use it?
It helps detect risky tools, unpinned server versions, dangerous options, and exposed secrets in the agent setup.

Command

Part of the security-suite plugin — 2 skills, 5 commands, 2 agents 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 commands/florianbruniaux/claude-code-plugins/security-check
Clone the repo
git clone --depth 1 https://github.com/FlorianBruniaux/claude-code-plugins

Or install security-suite, the plugin that ships this one along with the rest of its 2 skills, 5 commands, 2 agents.

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-check

README.md
[![agentmods](https://agentmods.dev/badge/commands/florianbruniaux/claude-code-plugins/security-check.svg)](https://agentmods.dev/commands/florianbruniaux/claude-code-plugins/security-check)
Your own site
<a href="https://agentmods.dev/commands/florianbruniaux/claude-code-plugins/security-check"><img src="https://agentmods.dev/badge/commands/florianbruniaux/claude-code-plugins/security-check.svg" alt="Measured on agentmods" height="20"></a>
Per session 11 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,658 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 4 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 $0.00011 $0.01658
Opus 5 $0.00005 $0.00829
Sonnet 5 $0.00002 $0.00332
Haiku 4.5 $0.00001 $0.00166

Measured yesterday against content hash bcab06eed43a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade B, and why

security-check scanned grade B with 4 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 yesterday.

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.

Reads agent configuration directorieslowAgent snooping

.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.

find .claude/hooks/ -type f 2>/dev/null

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Reads MCP configurationlowAgent snooping

mcp.json carries server URLs and auth tokens; reading it lets a mod discover and abuse other integrations.

cat .mcp.json 2>/dev/null

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Enumerates other installed skillslowAgent snooping

Other skills' SKILL.md files reveal prompts, capabilities and secrets that should be invisible to peers.

ls -la .claude/skills/ 2>/dev/null

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

grep -rn "curl\|wget\|nc \|ncat\|netcat\|base64\|eval\|exec\|/dev/tcp\|/dev/udp" .claude/hooks/ 2>/dev/null
plugins/security-suite/commands/security-check.md · 179 lines

How it starts

The opening of the file, as written. The whole thing — 179 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Security Check

Quick configuration security check against known threats database. Verifies your Claude Code setup for known malicious skills, vulnerable MCPs, dangerous patterns, and exposed secrets.

Time: ~30 seconds | Scope: Claude Code configuration only

Instructions

You are a security analyst. Check the user's Claude Code configuration against the threat intelligence database bundled at examples/commands/resources/threat-db.yaml. Produce a concise, actionable report.

Phase 1: Load Threat Database

Read examples/commands/resources/threat-db.yaml from this repository to load:

  • Known malicious authors and skills
  • CVE database for MCP servers
  • Suspicious patterns for hooks, agents, and config

Phase 2: MCP Server Audit

Read the user's MCP configuration:

# Global MCP config
cat ~/.claude.json 2>/dev/null | jq '.mcpServers // empty'

# Project MCP config
cat .mcp.json 2>/dev/null

Check against threat-db.yaml:

  • Any MCP server matching a CVE entry? → CRITICAL
  • Version pinning: are all MCP servers pinned to exact versions (not @latest)? → HIGH if unpinned
  • Any --dangerous-* flags in MCP args? → CRITICAL
  • Any MCP servers not on the Safe List (see guide/security-hardening.md §1.1)? → MEDIUM (flag for manual review)

Phase 3: Skills & Agents Audit

# List installed skills
ls -la .claude/skills/ 2>/dev/null
ls -la ~/.claude/skills/ 2>/dev/null

# List agents
ls -la .claude/agents/ 2>/dev/null
ls -la ~/.claude/agents/ 2>/dev/null

# Check agent tools field
grep -r "^tools:" .claude/agents/ 2>/dev/null
grep -r "^tools:" ~/.claude/agents/ 2>/dev/null

Check against threat-db.yaml:

  • Any skill/agent name matching malicious_skills entries? → CRITICAL
  • Any skill/agent author matching malicious_authors entries? → CRITICAL
  • Any agent with tools: Bash only? → HIGH
  • Any agent with overly broad tool access + vague description? → MEDIUM

Phase 4: Hook Security

Read the full file on GitHub · 179 lines

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. yesterday First seen · 179 lines · 11 tokens per session scan B bcab06eed43a

Subscribe to this mod's changes

security-check is a command published in the GitHub repository FlorianBruniaux/claude-code-plugins (40 stars, last pushed 3d ago), licensed MIT. It adds 11 tokens to every session and 1,658 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it B with 4 findings (reads agent configuration directories, reads mcp configuration, enumerates other installed skills). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-04.