windiff-version-diff-analysis

windiff-version-diff-analysis is a skill for Codex from ergrelet/windiff. It costs 140 tokens per session (2,478 once invoked), scanned A, original, GPL-3.0.

A tool for comparing Windows versions or patch levels and examining how system files changed between them. It uses the repository’s WinDiff command-line tool and databases to inspect security-relevant changes.

In plain words
What is it for?
Use it to compare files such as ntoskrnl.exe, ntdll.dll, win32k.sys, ci.dll, or cng.sys across Windows builds and interpret the resulting security-research diffs.
Why use it?
It removes the need to compare Windows binaries manually when investigating differences that may affect security. It helps reveal changed system interfaces, data types, and protection settings.

Skill for Codex

Written for Codex: agents/openai.yaml present.

Good fit Use it to compare files such as ntoskrnl.exe, ntdll.dll, win32k.sys, ci.dll, or cng.sys across Windows builds and interpret the resulting security-research diffs.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/ergrelet/windiff/windiff-version-diff-analysis
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 ergrelet/windiff --skill windiff-version-diff-analysis
Clone the repo
git clone --depth 1 https://github.com/ergrelet/windiff

Made for: 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 windiff-version-diff-analysis

README.md
[![agentmods](https://agentmods.dev/badge/skills/ergrelet/windiff/windiff-version-diff-analysis/github.svg)](https://agentmods.dev/skills/ergrelet/windiff/windiff-version-diff-analysis)
Your own site
<a href="https://agentmods.dev/skills/ergrelet/windiff/windiff-version-diff-analysis"><img src="https://agentmods.dev/badge/skills/ergrelet/windiff/windiff-version-diff-analysis/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for windiff-version-diff-analysis

Your own site · 80×15
<a href="https://agentmods.dev/skills/ergrelet/windiff/windiff-version-diff-analysis"><img src="https://agentmods.dev/badge/skills/ergrelet/windiff/windiff-version-diff-analysis.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 140 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,478 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00140 $0.02478
Opus 5.5 $0.00056 $0.00991
Sonnet 5.5 $0.00028 $0.00496
Haiku 4.5 $0.00014 $0.00248

Measured 2mo ago against content hash 12bb8af246ca, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

windiff-version-diff-analysis 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 2mo ago.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/make_config.py, scripts/windiff_diff.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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/windiff-version-diff-analysis/SKILL.md · 191 lines

The source is not reproduced here

Licensed GPL-3.0

The repository is licensed GPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

Files

What ships with it

7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 2mo ago First seen · 191 lines · 140 tokens per session scan A 12bb8af246ca

Subscribe to this mod's changes

windiff-version-diff-analysis is a skill published in the GitHub repository ergrelet/windiff (396 stars, last pushed 3d ago), licensed GPL-3.0. It adds 140 tokens to every session and 2,478 once invoked, about $0.0006 per session on Opus 5.5. 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

portable-executable-analysis

Perform static reverse engineering and analysis on Windows Portable Executable (PE) files to identify malicious indicators without executing the file. Use this skill during Incident Response, malware triage, or threat hunting to safely extract metadata, imported APIs, exported functions, embedded strings, and packed…

akashrpatil/awesome-offensive-security-skills · 73 tokens

har-api-reverse-engineering

Use this skill when an agent needs to call a website's hidden or undocumented API: capture real browser requests into a HAR file, derive the exact request shape, build a clean replayable client, verify it outside the browser, and reuse the verified client. Activates when a backend has no documented API, or when you…

JPeetz/agent-skills · 109 tokens

patch-diff-analyzer

Specialized in reverse-engineering compiled binaries (JARs, DLLs). Use this when the user asks to compare versions, find security fixes, or analyze binary patches.

zebbern/termstack · 41 tokens

bridge

Use when the user wants hyperflow's behavioral rules to apply outside the terminal CLI — in Claude Code Desktop, claude.ai web, or IDE extensions that don't load CLI plugins. Writes a managed doctrine block into the project's CLAUDE.md so autonomy + intent-routing + commit cadence + role separation + file-first rules…

jeremylongshore/tons-of-skills-marketplace · 126 tokens

ai-model-wechat

A guide for adding AI text generation to WeChat Mini Programs, lightweight applications that run inside WeChat.

TencentCloudBase/CloudBase-AI-Toolkit · 157 tokens

auth-web-cloudbase

CloudBase Web Authentication Quick Guide for frontend integration after auth-tool has already been checked. Provides concise and practical Web authentication solutions with multiple login methods and complete user management.

TencentCloudBase/CloudBase-AI-Toolkit · 38 tokens