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AI Agents with LangChain & Autonomous Workflows · Lesson

Retrievers & Contextual Compression

Turn a vector store into a tunable retriever, control how many documents come back, and use contextual compression to strip irrelevant text before it reaches the LLM.

From Vector Store to Retriever

A vector store knows how to search, but agents talk to a retriever — a thin interface with one job: given a query, return relevant documents.

Any vector store exposes as_retriever() to produce one.

retriever = vectorstore.as_retriever()
docs = retriever.invoke('How do I reset my password?')

Controlling k

The k parameter sets how many documents to return. Too few misses context; too many wastes tokens and adds noise.

retriever = vectorstore.as_retriever(
    search_kwargs={'k': 4}
)

All lessons in this course

  1. Document Loaders Explained
  2. Text Splitters & Embeddings
  3. Vector Stores for Retrieval
  4. Retrievers & Contextual Compression
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