Leanpub Header

Skip to main content

The Complete Beginner's Guide to Building Agentic AI

A Step-by-Step Roadmap from Fundamentals to Real-World Applications

The Complete Beginner's Guide to Building Agentic AI
This book is 100% completeLast updated on 2026-10-12

Curious about agentic AI but not sure where to start? This beginner-friendly guide takes you from the basics to building your own AI agents, even if you have no coding experience. Learn how agents work, choose the right tools and turn your ideas into practical, reliable solutions for real-world problems.

Minimum price

$25.00

$35.00

You pay

Author earns

$

Also available for 1 book credit with a Reader Membership

PDF
EPUB
WEB
APP
181
Pages
About

About

About the Book

This book takes you from knowing nothing about artificial intelligence or programming to understanding how agentic AI works and building functional AI agents for real-world problems. You will learn what agents are, how they think, when to use them, which tools and frameworks are right for your project and how to deploy reliable, secure and responsible systems. Every concept is explained clearly, every technical term is defined and every practical guide walks you through complete, working implementations.

Author

About the Author

Steve Publications

Steve is a technology professional with over 20 years of experience in software development, server infrastructure, cybersecurity, vulnerability research and reverse engineering. He specializes in analyzing complex systems, identifying weaknesses and improving security.

Beyond his professional work, Steve collaborates with researchers and industry experts to create practical technical books covering software development, cybersecurity, cloud computing, DevOps, AI and enterprise technologies. His goal is to help IT professionals, students and enthusiasts develop practical skills through clear explanations, real-world examples and hands-on exercises.

At Steve Publications, we use AI to assist with translation, proofreading and editing but not to replace the research, technical expertise or hands-on experience behind our books. Some authors publish under pseudonyms for privacy or professional reasons.

Every book is written, reviewed and maintained by experienced professionals, supported by a private community of over 420 engineers and researchers. We prioritize technical accuracy, practical value and regularly updated content over mass-produced AI-generated text.

We welcome experienced professionals interested in writing or reviewing books, especially in specialized and emerging technology fields. If you'd like to contribute, contact us with your area of expertise.

We stand behind our work. If a book doesn't meet your expectations, Leanpub offers a 60-day money-back guarantee.

Contents

Table of Contents

A Step-by-Step Roadmap from Fundamentals to Real-World Applications

Introduction

  1. What This Book Is and Is Not
  2. How to Read This Book
  3. The Core Idea: Agents Are Not Magic
  4. A Note on Time and Accuracy
  5. Who This Book Is For
  6. What You Will Be Able to Do
  7. Why Now?
  8. How This Book Approaches Complexity
  9. A Final Thought

Part I: Understanding the Landscape

Chapter 1: What Is Agentic AI - And Why Does It Matter?

  1. Learning Objectives
  2. From Chatbots to Agents
  3. What Makes Something Agentic?
  4. Real-World Examples of Agents at Work
  5. Why Agents Are Different from Earlier Automation
  6. When Agents Are Worth It - And When They Are Not
  7. The Promise and the Caveat

Chapter 2: The Building Blocks - AI, LLMs and Where Agents Fit In

  1. Learning Objectives
  2. What Artificial Intelligence Actually Means Today
  3. How Large Language Models Work
  4. Generative AI: Creation from Patterns
  5. From Models to Assistants to Agents
  6. The Continuum: Tools, Chatbots, Assistants, Agents, Autonomy
  7. Why This Matters for Building Agents

Chapter 3: How an AI Agent Thinks - The Core Architecture

  1. Learning Objectives
  2. The Big Picture: An Agent as a System
  3. The Brain: Language Models and Reasoning
  4. The Instructions: System Prompts and Role Definition
  5. The Memory: Short-Term and Long-Term Context
  6. The Hands and Eyes: Tools, APIs and Knowledge Sources
  7. The Feedback Loop: Reflection, Correction and Improvement
  8. Putting It All Together: A Complete Agent Architecture
  9. Common Agent Patterns
  10. The Mental Model for What Comes Next

Part II: Planning Your Agent

Chapter 4: Finding the Right Problem

  1. Learning Objectives
  2. The Agent Trap
  3. Characteristics of Agent-Suitable Problems
  4. Signs You Need an Agent - And Signs You Do Not
  5. Mapping Business Problems to Agent Capabilities
  6. Estimating Value vs Complexity
  7. Common Mistakes in Agent Project Selection
  8. A Practical Exercise

Chapter 5: Designing Your Agent - Goals, Boundaries and Guardrails

  1. Learning Objectives
  2. The Importance of Design
  3. Defining Clear Objectives and Success Criteria
  4. Setting Scope: What Your Agent Will and Will Not Do
  5. Designing Safety Boundaries and Constraints
  6. Human-in-the-Loop: When to Require Approval
  7. Drafting Your Agent Specification Document
  8. Why This Matters

Part III: Tools and Technologies

Chapter 6: Picking Your Model - Providers, Pricing and Trade-offs

  1. Learning Objectives
  2. The Model Is the Engine, But Not the Whole Car
  3. Key Model Capabilities for Agents
  4. Major Model Providers: Overview and Comparison
  5. Open-Source vs Proprietary Models
  6. Understanding Pricing: Tokens, Latency and Budget
  7. Matching Models to Your Agent’s Needs
  8. The Bottom Line

Chapter 7: The Developer Toolkit - Languages, Frameworks and Platforms

  1. Learning Objectives
  2. Programming Languages: Python, JavaScript and Others
  3. Agent Frameworks: What They Are and Why They Exist
  4. Low-Code and No-Code Platforms for Agents
  5. Choosing the Right Stack for Your Skill Level
  6. Setting Up Your Development Environment
  7. A Note on Framework Fatigue

Part IV: Building Agents - Core Skills

Chapter 8: Writing Instructions That Work - The Art of System Prompts

  1. Learning Objectives
  2. What a System Prompt Does - And Does Not Do
  3. Structure of an Effective System Prompt
  4. Specifying Tasks, Tone and Constraints
  5. Examples and Few-Shot Prompting
  6. Iterating and Testing Your Prompts
  7. Common Prompt Pitfalls
  8. A Complete Example

Chapter 9: Giving Agents Tools - APIs, Functions and Function Calling

  1. Learning Objectives
  2. What It Means for an Agent to “Use a Tool”
  3. Understanding Function Calling and Structured Outputs
  4. Building and Registering Tools Your Agent Can Call
  5. Connecting to APIs, Databases and Services
  6. Error Handling and Graceful Failures

Chapter 10: Memory and Context - Keeping Track of What Matters

  1. Learning Objectives
  2. Context Windows: What the Model Can “Remember” Right Now
  3. Short-Term Memory: Conversation History and State
  4. Long-Term Memory: Databases, Vectors and Persistent Storage
  5. Embeddings and Vector Databases Explained
  6. Managing Memory: Including and Forgetting Information

Chapter 11: Knowledge and RAG - Grounding Agents in Real Information

  1. Learning Objectives
  2. Why RAG: Solving Hallucination and Outdated Knowledge
  3. How Retrieval-Augmented Generation Works
  4. Chunking, Embedding and Indexing Your Documents
  5. Building a RAG Pipeline Step by Step
  6. Evaluating RAG Quality and Improving Results

Part V: Building End-to-End - Practical Guides

Chapter 12: Your First Agent - A Complete Step-by-Step Build

  1. Learning Objectives
  2. Choosing the Problem: A Research Assistant Agent
  3. Installing Dependencies and Setting Up
  4. Writing the System Prompt
  5. Connecting the Model
  6. Building the Search Tool
  7. Creating the Agent
  8. Running and Testing Your First Agent
  9. Troubleshooting Common Issues
  10. Iterating on Your Agent

Chapter 13: A Tool-Using Agent - Automating Real Tasks

  1. Learning Objectives
  2. Defining the Use Case: A Travel Planning Agent
  3. Designing Tools: Search, Weather and APIs
  4. Implementing the Flight Search Tool
  5. Implementing the Weather Tool
  6. Implementing the Hotel Search Tool
  7. Orchestrating Multi-Step Workflows
  8. Testing and Refining

Chapter 14: A Knowledge-Grounded Agent - Building on Your Data

  1. Learning Objectives
  2. Use Case: A Company Knowledge Assistant
  3. Preparing and Uploading Documents
  4. Setting Up RAG with a Vector Store
  5. Writing Prompts for Grounded Responses
  6. Evaluating Accuracy and Citation Quality

Part VI: Scaling Up

Chapter 15: Multi-Step Workflows and State Management

  1. Learning Objectives
  2. Breaking Down Complex Tasks into Steps
  3. State Machines and Workflow Orchestration
  4. Handling Partial Failures and Retries
  5. Preserving and Restoring Agent State
  6. When to Use a Workflow Engine vs Custom Code

Chapter 16: Multi-Agent Systems - When One Is Not Enough

  1. Learning Objectives
  2. Why Use Multiple Agents
  3. Agent Specialization and Role Division
  4. Communication Patterns Between Agents
  5. Orchestrator vs Peer Architectures
  6. Practical Example: A Collaborative Research Team

Chapter 17: Deploying Your Agent - From Prototype to Production

  1. Learning Objectives
  2. Deployment Environments: Local, Cloud, Containers
  3. Exposing Your Agent via Web Interfaces and APIs
  4. Managing Keys, Secrets and Configuration
  5. Scaling: Handling Multiple Users and Requests
  6. Monitoring, Logging and Observability

Part VII: Making It Real - Reliability, Security and Evaluation

Chapter 18: Making Agents Reliable - Testing, Validation and Error Handling

  1. Learning Objectives
  2. Types of Agent Failures: Hallucination, Wrong Tools, Infinite Loops
  3. Systematic Testing Strategies for Agents
  4. Structured Outputs and Schema Validation
  5. Retries, Fallbacks and Graceful Degradation
  6. Building a Feedback Loop for Continuous Improvement

Chapter 19: Securing Your Agent - Threats, Attacks and Defenses

  1. Learning Objectives
  2. Security Risks Unique to Agents
  3. Prompt Injection and How to Defend Against It
  4. Sandboxing and Limiting Agent Permissions
  5. Protecting Data Privacy and Confidentiality
  6. Secure API and Tool Integration
  7. A Security Checklist for Agent Developers

Chapter 20: Evaluating Agent Performance - Metrics That Matter

  1. Learning Objectives
  2. Defining Success Metrics for Different Agent Types
  3. Accuracy, Completion Rate and Task Success
  4. Cost, Latency and Efficiency Metrics
  5. User Satisfaction and Behavioral Metrics
  6. Running Evaluations and Iterating

Part VIII: Real-World Applications

Chapter 21: Agents for Business and Operations

  1. Learning Objectives
  2. Customer Service and Support Agents
  3. Sales and Lead Qualification Agents
  4. Internal Operations and Employee Assistants
  5. Document Processing and Compliance
  6. Limitations and Risks in Business Deployment

Chapter 22: Agents for Development and Data

  1. Learning Objectives
  2. Coding Assistants and Autonomous Development
  3. Data Analysis and Visualization Agents
  4. DevOps and Infrastructure Agents
  5. When Agents Help - And When They Create More Work

Chapter 23: Agents for Personal Use, Education and Creativity

  1. Learning Objectives
  2. Personal Productivity and Organization Agents
  3. Learning and Tutoring Agents
  4. Creative Collaboration: Writing, Design, Content
  5. Ethics and Privacy in Personal Agents

Part IX: Trade-offs, Responsibility and the Future

Chapter 24: The Honest Assessment - Costs, Trade-offs and Realistic Expectations

  1. Learning Objectives
  2. Financial Costs: Token Usage, Infrastructure, Maintenance
  3. Reliability Costs: Error Rates and Human Oversight
  4. Complexity and Organizational Overhead
  5. When Conventional Software Is Still Better
  6. Building the Right Level of Autonomy

Chapter 25: Responsible AI - Ethics, Governance and Human Accountability

  1. Learning Objectives
  2. Why Responsibility Matters More for Agents
  3. Bias, Fairness and Harm Prevention
  4. Transparency and Explainability
  5. Regulatory Landscape and Compliance
  6. Keeping Humans in Charge

Chapter 26: Your Roadmap Forward - Starting Your First Project

  1. Learning Objectives
  2. Choosing Your First Agent Project
  3. A 30-60-90 Day Learning and Building Plan
  4. Joining Communities and Staying Current
  5. Anticipating the Future of Agentic AI
  6. Final Thoughts: Building with Judgment

Conclusion: From Consumer to Builder

Glossary

References

Recommended Learning Resources

  1. Books and Courses
  2. Frameworks and Tools
  3. Communities
  4. Newsletters and Blogs
  5. Practice and Projects

Get the free sample chapters

Click the buttons to get the free sample in PDF or EPUB, or read the sample online here

The Leanpub 60 Day 100% Happiness Guarantee

Within 60 days of purchase you can get a 100% refund on any Leanpub purchase, in two clicks.

See full terms...

Earn $8 on a $10 Purchase, and $16 on a $20 Purchase

We pay 80% royalties on purchases of $7.99 or more, and 80% royalties minus a 50 cent flat fee on purchases between $0.99 and $7.98. You earn $8 on a $10 sale, and $16 on a $20 sale. So, if we sell 5000 non-refunded copies of your book for $20, you'll earn $80,000.

(Yes, some authors have already earned much more than that on Leanpub.)

Learn more about writing on Leanpub

Free Updates. DRM Free.

If you buy a Leanpub book, you get free updates for as long as the author updates the book! Many authors use Leanpub to publish their books in-progress, while they are writing them. All readers get free updates, regardless of when they bought the book or how much they paid (including free).

Most Leanpub books are available in PDF (for computers) and EPUB (for phones, tablets and Kindle). The formats that a book includes are shown at the top right corner of this page.

Finally, Leanpub books don't have any DRM copy-protection nonsense, so you can easily read them on any supported device.

Learn more about Leanpub's ebook formats and where to read them

Write and Publish on Leanpub

You can use Leanpub to easily write, publish and sell in-progress and completed ebooks and online courses!

Leanpub is a powerful platform for serious authors, combining a simple, elegant writing and publishing workflow with a store focused on selling in-progress ebooks.

Leanpub is a magical typewriter for authors: just write in plain text, and to publish your ebook, just click a button. (Or, if you are producing your ebook your own way, you can even upload your own PDF and/or EPUB files and then publish with one click!) It really is that easy.

Learn more about writing on Leanpub