nextjs-security-testing

nextjs-security-testing is a skill for Claude Code, Codex from xAmirHamza77/PenKit51. It costs 26 tokens per session (3,792 once invoked), scanned B, original, no licence file.

A security-testing guide for Next.js applications, including the App Router, Server Actions, React Server Components, and Edge runtime. Next.js is a framework for building web applications.

In plain words
What is it for?
Use it to plan and perform security checks on routing, server actions, server-rendered components, and edge-deployed code.
Why use it?
It helps developers check parts of Next.js that can handle requests, server code, or data in ways that may create security bugs.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit Use it to plan and perform security checks on routing, server actions, server-rendered components, and edge-deployed code.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/xamirhamza77/penkit51/nextjs-security-testing
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.

Any agent
npx skills add xAmirHamza77/PenKit51 --skill nextjs-security-testing
Clone the repo
git clone --depth 1 https://github.com/xAmirHamza77/PenKit51

Made for: Claude Code, Codex.

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 nextjs-security-testing

README.md
[![agentmods](https://agentmods.dev/badge/skills/xamirhamza77/penkit51/nextjs-security-testing.svg)](https://agentmods.dev/skills/xamirhamza77/penkit51/nextjs-security-testing)
Your own site
<a href="https://agentmods.dev/skills/xamirhamza77/penkit51/nextjs-security-testing"><img src="https://agentmods.dev/badge/skills/xamirhamza77/penkit51/nextjs-security-testing.svg" alt="Measured on agentmods" height="20"></a>
Per session 26 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,792 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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 $0.00026 $0.03792
Opus 5 $0.00013 $0.01896
Sonnet 5 $0.00005 $0.00758
Haiku 4.5 $0.00003 $0.00379

Measured 7d ago against content hash 9c4813e48126, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade B, and why

nextjs-security-testing scanned grade B with 1 finding 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 7d 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.

Harvests environment variablesmediumData exfiltration

Enumerating or grepping the environment for keys collects credentials unrelated to what the mod says it does.

Object.keys(process.env).filter(k => k.startsWith('NEXT_PUBLIC_'))

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

skills/nextjs-security-testing/SKILL.md · 484 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 7d ago First seen · 484 lines · 26 tokens per session scan B 9c4813e48126

Subscribe to this mod's changes

nextjs-security-testing is a skill published in the GitHub repository xAmirHamza77/PenKit51 (2 stars, last pushed 2mo ago), with no licence file. It adds 26 tokens to every session and 3,792 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it B with 1 finding (harvests environment variables). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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