retrieval

Definition

Fetching relevant passages from an external store — documents, a vector index, a database — so the model can condition on them. It is the R in RAG, and the usual motivation is knowledge the weights lack: recent events, private documents, anything that changes faster than you retrain. Unlike a search engine, the results are selected for a model to consume, so chunking and ranking are tuned for a context window rather than for a human reader.

Explainers using this term

• Paper Explained: Retrieval-Augmented Skill Optimization via Cross-Harness Adaptation — Borrow Someone Else's Skill, Rewrite It for Your Own HarnessRetrieval-Augmented Skill Optimization via Cross-Harness Adaptation
• Paper Explained: D-RAC — Normalize Everything to PDF, Read the Pages Once, Then Chunk by IDDocument Retrieval-Aware Chunking (D-RAC): Universal Retrieval-Aware Ingestion of Enterprise Documents via PDF Normalization and Multimodal Markdown Conversion
• Paper Walkthrough — Beyond Retrieval: LatentStream Turns Retrieved Video Into Latent MemoryBeyond Retrieval: Progressive Latent Memory Evolution for Streaming Video Understanding

In the textbook

• Using What It Never Learned — Embeddings and Retrieval