RAG in 2025: State of the Art and the Road Forward — Tengyu Ma, MongoDB (Voyage AI)

Retrieval Augmented Generation (RAG) & Large Language Models (LLMs) - RAG is essential for enterprises to incorporate proprietary information into LLMs, addressing the limitations of out-of-the-box models [2][3] - RAG is considered a more reliable, faster, and cheaper approach compared to fine-tuning and long context windows for utilizing external knowledge [7] - The industry has seen significant improvements in retrieval accuracy over the past 18 months, driven by advancements in embedding models [11][12] - The industry averages approximately 80% accuracy across 100 datasets, indicating a 20% potential improvement headroom in retrieval tasks [12][13] Vector Embeddings & Storage Optimization - Techniques like matryoshka learning and quantization can reduce vector storage costs by up to 100x with minimal performance loss (5-10%) [15][16][17] - Domain-specific embeddings, such as those customized for code, offer better trade-offs between storage cost and accuracy [21] RAG Enhancement Techniques - Hybrid search, combining lexical and vector search with re-rankers, improves retrieval performance [18] - Query decomposition and document enrichment, including adding metadata and context, enhance retrieval accuracy [18][19][20] Future of RAG - The industry predicts a shift towards more sophisticated models that minimize the need for manual "tricks" to improve RAG performance [29][30] - Multimodal embeddings, which can process screenshots, PDFs, and videos, simplify workflows by eliminating the need for separate data extraction and embedding steps [32] - Context-aware and auto-chunking embeddings aim to automate the trunking process and incorporate cross-trunk information, optimizing retrieval and cost [33][36]