Agent Skills Fundamentals

Learn what AI agent skills are, how to design them, and how they work. Start here if you're new to building or using agent skills.

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Fundamentals For Everyone

What are agent skills and why they matter

A beginner-friendly introduction to AI agent skills: what they are, why they're transforming how we work with AI, and how to think about them.

fundamentals introduction concepts
· 5 min read
Fundamentals For Everyone

Agent skills glossary: skill, tool, MCP, plugin, agent, prompt

Plain-language definitions for the AI agent vocabulary that gets used loosely everywhere: what's a skill, what's a tool, how MCP fits in, how plugins differ, and what an agent actually is.

fundamentals glossary terminology
· 9 min read
Fundamentals Technical

Skill design principles

Foundational principles for designing composable, predictable, and maintainable skill files including single responsibility and idempotency.

design principles architecture
· 8 min read
Fundamentals Developer

Testing and debugging agent skills

A practical guide to testing agent skills: unit tests, integration tests with mock LLM responses, snapshot tests, and debugging techniques.

testing debugging ci-cd
· 5 min read
Fundamentals Technical

How to design AI agent skills

A deep dive into the four pillars of skill design: clear descriptions, well-typed parameters, error handling, and predictable output.

design architecture best-practices
· 8 min read
Fundamentals Developer

Security Considerations for Agent Skills

A practical guide to securing agent skills: input sanitization, least privilege, sandboxing, secrets management, and audit logging.

security best-practices compliance
· 5 min read
Fundamentals For Everyone

How agents actually work under the hood

The think-act-observe loop, tool calling, and context windows explained without the hype. What's really happening when an AI agent does something for you.

fundamentals how-it-works concepts
· 7 min read
Fundamentals For Everyone

Writing effective skill instructions

The words you use to describe a skill matter more than the code behind it. How to write instructions that agents actually follow.

prompting design instructions
· 7 min read
Fundamentals For Everyone

When NOT to use an agent

Agents are powerful, but they're not the answer to everything. Sometimes a script, a form, or a human is the better choice. Here's how to tell the difference.

fundamentals decision-making critical-thinking
· 7 min read
Fundamentals Technical

The cost of bad tool descriptions

Your agent keeps picking the wrong tool. The problem isn't the code, it's the description. Real examples of tool descriptions that fail and how to fix them.

design descriptions debugging
· 5 min read
Fundamentals Technical

Prompt engineering vs skill design

They sound similar but they solve different problems. When to write a better prompt and when to build a skill instead.

prompting design fundamentals
· 8 min read
Fundamentals For Everyone

Agent memory patterns for non-developers

What 'memory' actually means for AI agents, why your assistant forgets things, and how to work with memory instead of fighting it.

memory concepts practical
· 6 min read