security-and-hardening SKILL.md skillA

security-and-hardening from jpeetz/agent-skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

mdr add jpeetz/agent-skills/security-and-hardening@git:20261012.4b2f1b0

Pins git:20261012.4b2f1b0 in mdr.lock. Pin the fingerprint instead.

Audit grade

A, 17 of 17 checks passed

Kind

SKILL.md skill

Repository

jpeetz/agent-skills

Path

skills/security/security-and-hardening/SKILL.md

Versions recorded

1

Latest version

git:20261012.4b2f1b0, committed Oct 12, 2026

Size

9,249 bytes

Repository stars

16

License

none declared

Use this skill when auditing code for vulnerabilities, handling user input, authentication, data storage, or external integrations. Hardens code against OWASP Top 10 with a three-tier boundary system, dependency auditing, data privacy, and LLM safety.

Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.

What the file says

# Security and Hardening

## Overview

Security-first development practices for web applications. Treat every external input as hostile, every secret as sacred, and every authorization check as mandatory. Security isn't a phase — it's a constraint on every line of code that touches user data, authentication, or external systems.

## When to Use

- Building anything that accepts user input
- Implementing authentication or authorization
- Storing or transmitting sensitive data
- Integrating with external APIs or services
- Adding file uploads, webhooks, or callbacks
- Handling payment or PII data
- Building LLM/AI features (chatbots, summarizers, agents, RAG)

## Process: Threat Model First

Controls bolted on without a threat model are guesses. Before hardening, spend five minutes thinking like an attacker:

1. **Map the trust boundaries.** Where does untrusted data cross into your system? HTTP requests, form fields, file uploads, webhooks, third-party APIs, message queues, and LLM output.
2. **Name the assets.** What's worth stealing or breaking? Credentials, PII, payment data, admin actions.
3. **Run STRIDE over each boundary** — a quick lens, not a ceremony:
…

Read the whole file at its exact version.

How to install

mdr add jpeetz/agent-skills/security-and-hardening@sha256:196ca4f17ee20f4d

[![mdr](https://markdownregistry.com/badge/art_tss6el653ixsh6ct.svg)](https://markdownregistry.com/a/art_tss6el653ixsh6ct)

Versions

The registry has recorded 1 version of this file, committed on Oct 12, 2026.

Audit of the latest version

Source

API

GET https://markdownregistry.com/api/v1/artifacts/art_tss6el653ixsh6ct
GET https://markdownregistry.com/api/v1/resolve?ref=jpeetz/agent-skills/security-and-hardening
GET https://markdownregistry.com/api/v1/blob/196ca4f17ee20f4d4c3984088fdd015633d6ed5725a3fa798b6e8a0975c87228

Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.

Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.

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