addyosmani/agent-skills

security-and-hardening

Hardens code against vulnerabilities. Use when handling user input, authentication, data storage, or external integrations. Use when building any feature that accepts untrusted data, manages user sessions, or interacts with third-party services. Use when personal data or privacy compliance (GDPR, CCPA) is involved.

32K installs 92K starsUpdated Aug 29, 2026License: MIT

Install

npx skills add addyosmani/agent-skills@security-and-hardening

Runs in your terminal. Adds the skill globally for Claude Code, Cursor, Codex and others; add -g -y to skip prompts.

What it does

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 Process:…

Excerpt from the skill's own SKILL.md. Read the full file on GitHub before installing: skills run with your agent's permissions.

View source on GitHub

Before you install

Skills are plain text instructions the agent follows, sometimes with scripts. Check the source, prefer repositories with many installs and stars, and read any script it ships.

Categories

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