Let's Build It: AI Chatbot with RAG in .NET Using Your Data

Build a Retrieval-Augmented Generation (RAG) chatbot that can answer questions using your data.

About This Course

Retrieval-Augmented Generation (RAG) is a transformative AI architecture that enables large language models to answer questions using your specific data rather than relying solely on their training knowledge. It combines the power of semantic search through vector embeddings with the natural language capabilities of LLMs, creating AI systems that can provide accurate, contextual, and verifiable responses grounded in your custom knowledge base. RAG has become the cornerstone of modern AI applications, powering everything from intelligent customer support and internal knowledge bases to research assistants and domain-specific Q&A systems. Unlike traditional chatbots or pure LLM solutions, RAG-based systems can cite their sources, stay current with your latest data, and dramatically reduce hallucinations by anchoring responses in retrieved documents. Companies from startups to enterprises are adopting RAG to unlock the value in their documentation, support tickets, and proprietary content. In this hands-on course, instructor James Charlesworth will take you from understanding vector embeddings and semantic search to building a production-ready RAG chatbot in .NET with OpenAI, Pinecone, and advanced techniques like HYDE for enhanced retrieval accuracy.

Course Curriculum

4h 25m 6 sections
Welcome
02:28 Free preview
What will you learn in this course?
00:59 Free preview
Who is the course for and prerequisites
02:21 Free preview
What is a Vector?
03:23
Semantic Search vs Keyword Search
06:58
Creating Embeddings With A Large Language Model (LLM)
17:12
Searching With Vectors (Cosine Similarity & Euclidean Distance)
07:03
Introduction To Pinecone
03:34
Vector Search Architecture in .NET
08:30
Creating Embeddings From Wikipedia
14:27
Pinecone Index Design & Upsert
16:14
Adding a Key Value Store
10:25
Building A Search Endpoint
16:06
Sentence Splitting and Chunking
36:51
Retrieval Augmented Generation (RAG) Explained
07:55
Writing LLM Prompts For RAG
06:36
Implementing A Generation Step In C#
09:13
Answering Questions About Your Data
09:06
Creating An Index Of YouTube Transcripts
09:37
What Are Hypothetical Document Embeddings
08:27
Generating A HYDE Query
13:08
Augmented Retrieval And Fusion Step (RRF/MMR)
10:30
Building A Basic Chatbot in C#
12:35
Tool Calling With LLMs
06:21
Adding A Database Search Tool
13:59
Multi Search Operations
08:17
Using Your Own Data
02:31

Meet Your Instructor

James Charlesworth

James Charlesworth

James is a Director of Engineering, O'Reilly author, speaker, and YouTuber with 20 years of experience in the tech industry. He has worked across startups and publicly listed tech companies, helping to build and scale software products. James focuses on teaching product skills to engineers, building high-performing product engineering teams, and defining the "Product Engineer" career path. He shares practical advice on software engineering, product development, and career growth through his Train to Code YouTube channel.

View all courses by James Charlesworth

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