Gen-AI Developer Classroom notes 12/Jan/2026

Langchain

• This is an opensource libary which
  • abstracts the llm models
  • base components for building
    • rags
    • agents (langgraph)
  • tracing (observability) => Langsmith

• Alternatives:

  • llamaIndex
  • AutoGen
  • CrewAI

• Langchain ecosystem
  

Hello – langchain

• Lets create a new project

mkdir hello-langgchain
cd hello-langgchain
uv init .
uv add langchain ipykernel

• open vscode and ctrl+shift+p => Python Interpreter
  

• create a new folder called as notebooks and create a file called as hello-langchain.ipynb and select kernel

• We need to understand two terms

  • model: Name of the model which you are connecting
  • model_provider: Provider of the model (GCP/AWS/Azure/….) if applicable.

• to use a new model we need a package langchain-openai, langchain-ollama etc

• Refer Here for basic example.

• Summary: Langchain abstracts models from your agents/rags.