Sample code for: LangChain Tutorial: Build Your First Chains and Agents

[martin-martin]

Where to put new files:

• New files should go into a top-level subfolder, named after the article slug. For example: my-awesome-article

How to merge your changes:

1. Make sure the CI code style tests all pass (+ run the automatic code formatter if necessary).
2. Find an RP Team member on Slack and ask them to review & approve your PR.
3. Once the PR has one positive ("approved") review, GitHub lets you merge the PR.
4. 🎉

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Code examples for the LangChain Tutorial: Build Your First Chains and Agents tutorial. Files live in the langchain-tutorial/ top-level folder, named after the article slug.

The langchain_intro/ package holds the final chatbot.py (chat model → prompt templates → LCEL chain → ChromaDB RAG retriever → tool-calling agent), alongside create_retriever.py (builds the vector database) and tools.py. Also included: data/reviews.csv, a requirements.txt with the pinned versions from the tutorial, and a .env.example.

The code was executed end-to-end against the OpenAI API and verified before pushing (ruff format + ruff check clean against the repo's pinned ruff).