LangGraph Tutorial

Prerequisites

• Python programming experience
• Basic understanding of LLMs and API interactions
• No prior LangChain experience required
• Python 3.13 environment

Required APIs/Tools

• OpenAI API key for LLM interactions
• UV for environment management
• Ruff for code formatting and linting

Environment Setup

This project uses environment variables for configuration. To set up:

1. Copy .env.template to .env:

   cp .env.template .env

2. Edit .env and fill in your API keys:

   • OPENAI_API_KEY: Your OpenAI API key
   • TAVILY_API_KEY: Your Tavily API key
   • Optional: LANGSMITH_API_KEY and other configuration

3. The .env file is ignored by git to keep your keys secure

Project Structure

.
├── .DS_Store
├── .env.template
├── .gitignore
├── LICENSE
├── Makefile
├── README.md
├── pyproject.toml
├── solutions
│   ├── .DS_Store
│   ├── unit1
│   │   ├── .DS_Store
│   │   └── __init__.py
│   └── unit2
│       ├── .DS_Store
│       └── __init__.py
├── src
│   ├── .DS_Store
│   ├── __init__.py
│   ├── config.py
│   └── exercises
│       ├── .DS_Store
│       ├── __init__.py
│       ├── unit1
│       │   ├── __init__.py
│       │   ├── exercise1.py
│       │   ├── exercise2.py
│       │   └── exercise3.py
│       └── unit2
│           ├── __init__.py
│           ├── exercise1.py
│           ├── exercise2.py
│           └── exercise3.py
└── tests
    ├── .DS_Store
    ├── __init__.py
    ├── conftest.py
    ├── test_unit1
    │   ├── .DS_Store
    │   ├── __init__.py
    │   ├── test_exercise1.py
    │   ├── test_exercise2.py
    │   └── test_exercise3.py
    └── test_unit2
        ├── .DS_Store
        ├── __init__.py
        ├── test_exercise1.py
        ├── test_exercise2.py
        └── test_exercise3.py

Development Workflow

1. Environment Setup:

   make setup  # Creates venv and installs dependencies

2. Development:

   make format  # Format code
   make lint    # Check style
   make test    # Run tests

3. Testing:

   • Unit tests for exercise validation
   • Integration tests with real APIs
   • Mocked tests for development