RAG is to enhance the generation capabilities of a language model by integrating external knowledge sources (DB, KB etc). This is done by retrieving relevant information from a knowledge base or document store and using it to inform or augment the model's responses.

Langchain is a library specifically designed to facilitate the development of applications using LLMs. It provides tools and utilities to build complex NLP pipelines with ease.

Alertfor is a SaaS product that combines LLMs with agents to provide automated search.

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