LangChain 20 Drills: Build AI Agents with create_agent & RAG

About this course

This course contains the use of artificial intelligence."

I keep hearing about AI agents. I can run the demos. But the moment I try to shape my own idea, I freeze.

" — This course exists to get you out of exactly that state.

LangChain is a common layer that lets you write against any LLM the same way. And in 1.x, agent development has been consolidated into a single function: create_agent. Hand it a model, some tools, and memory, and you get an agent that decides on its own to call a tool, remembers the conversation, and searches documents when it needs to. This course builds those parts up one at a time, hands on, through 20 practical drills.

Learning follows a roadmap of 7 chapters. Once Section 0 has your environment ready, Section 1 nails the foundation: calling an LLM, streaming, and system prompts. Section 2 covers prompt templates and the technique that pays off most in real work—structured output, receiving the LLM's reply as a Python type (Pydantic) instead of a string—carried all the way through to building your own review analyzer.

Section 3 is the peak of the course: tools and agents. The "magic" that agents look like to so many learners is taken apart, starting from how a @tool decorator's docstring becomes the LLM's instructions. You'll build an agent that picks between a calculator and a unit converter with create_agent, then peek into the message history to see what the agent thought and which tool it called—the basics of debugging.

Section 4 covers RAG (answering by searching) end to end. Loading and splitting documents, similarity search over embeddings and a vector store, a QA bot that answers questions about fictional company rules, and finally wrapping retrieval in @tool to integrate it into an agent—the "it clicked!

" moment where Section 3 and RAG connect. In Section 5 you give a chatbot conversational memory (checkpointer and thread_id) so it remembers the name you just gave it, and in the final Section 6 you

Prices, discounts and availability are set by Udemy. We may earn a commission when you purchase through links on this site.