security-scanning

security-scanning is a skill for Claude Code from nexus-substrate/nexus-agents. It costs 51 tokens per session (1,880 once invoked), scanned A, original, MIT.

A security-review procedure for handling CodeQL and secret-scanning alerts. CodeQL finds some security problems in source code, while secret scanning looks for exposed passwords, tokens, and similar credentials.

In plain words
What is it for?
Use it to check open CodeQL and secret-scanning alerts, prioritize critical issues, and guide fixes for problems such as unsafe shell commands, weak randomness, regular-expression denial of service, and incomplete sanitization.
Why use it?
It organizes alert triage by severity and provides repair patterns for common findings, helping teams address security issues after scans or during system reviews.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Part of the nexus-agents plugin — 33 skills, 16 agents, 1 hook 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 skills/nexus-substrate/nexus-agents/security-scanning
Any agent
npx skills add nexus-substrate/nexus-agents --skill security-scanning
Clone the repo
git clone --depth 1 https://github.com/nexus-substrate/nexus-agents

Made for: Claude Code.

Or install nexus-agents, the plugin that ships this one along with the rest of its 33 skills, 16 agents, 1 hook.

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-scanning

README.md
[![agentmods](https://agentmods.dev/badge/skills/nexus-substrate/nexus-agents/security-scanning.svg)](https://agentmods.dev/skills/nexus-substrate/nexus-agents/security-scanning)
Your own site
<a href="https://agentmods.dev/skills/nexus-substrate/nexus-agents/security-scanning"><img src="https://agentmods.dev/badge/skills/nexus-substrate/nexus-agents/security-scanning.svg" alt="Measured on agentmods" height="20"></a>
Per session 51 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,880 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 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 5.1 $0.00051 $0.01880
Opus 5 $0.00026 $0.00940
Sonnet 5 $0.00010 $0.00376
Haiku 4.5 $0.00005 $0.00188

Measured 6d ago against content hash 95cb8da9bb2f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

security-scanning scanned grade A with 0 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 6d ago.

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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/security-scanning/SKILL.md · 173 lines

How it starts

The opening of the file, as written. The whole thing — 173 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Security Scanning Skill

Trigger Conditions

Run when ANY occur:

  • System review (Phase 4 integration)
  • New CodeQL alerts appear after CI
  • Secret scanning alert notification
  • Manual request ("check security alerts")

Phase 1: Triage Alerts

# Check CodeQL alerts (open only)
gh api repos/{owner}/{repo}/code-scanning/alerts \
  --jq '[.[] | select(.state == "open")] | length'

# Check secret scanning alerts
gh api repos/{owner}/{repo}/secret-scanning/alerts \
  --jq '[.[] | select(.state == "open")] | length'

Categorize by severity: critical > high > medium > low.

Phase 2: CodeQL Fixes

Priority order for CodeQL alert categories:

Category Fix Pattern
js/shell-command-constructed-from-input Use execFile() or validate inputs
js/insecure-randomness Replace Math.random() with crypto.randomInt()
js/biased-cryptographic-random Use crypto.randomInt() or rejection sampling
js/polynomial-redos Bound quantifiers, use [ \t]* not \s*
js/incomplete-sanitization Single-quote shell escaping
js/incomplete-multi-character-sanitization Loop-based stripping for unclosed tags
js/missing-rate-limiting Add rate limiter middleware
js/incomplete-url-scheme-check Zod .refine() for HTTP/HTTPS only

For each alert:

  1. Read the affected file and understand the context
  2. Write a test that reproduces the vulnerability
  3. Apply the fix
  4. Run tests to verify no regressions

Read the full file on GitHub · 173 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. 6d ago First seen · 173 lines · 51 tokens per session scan A 95cb8da9bb2f

Subscribe to this mod's changes

security-scanning is a skill published in the GitHub repository nexus-substrate/nexus-agents (18 stars, last pushed yesterday), licensed MIT. It adds 51 tokens to every session and 1,880 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

local-ai-agents

Build local-first AI agents that run entirely on a developer workstation with Microsoft Foundry Local and Qwen function-calling models. Covers Small Language Models (SLMs), the OpenAI-compatible local endpoint, sandboxed local tools, local RAG with Chroma, local MCP servers, hybrid cloud/local routing, and the…

microsoft/ai-agents-for-beginners · 200 tokens

chronicle

Analyze Copilot session history for standup reports, usage tips, session search, and session reindexing. Use when the user asks for a standup, daily summary, usage tips, workflow recommendations, wants to search or find past sessions by keyword/file/PR, wants to reindex their session store, or asks about deleting…

microsoft/vscode · 72 tokens

chat-pet-sprite-creation

Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.

microsoft/vscode · 53 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens

next-cache-components-adoption

Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…

vercel/next.js · 95 tokens