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The RAG Obituary: Killed by agents, buried by context windows

nicolasbustamante.com

41–50 of 185 posts

Re: The RAG Obituary: Killed by agents, buried by context windows

#41
post #28

Earlier quoted context omitted.

It's mind blowing. It's so simple, elegant and... effective! Grep+glob and a lot of iterations is all we need.

We always suspected find+grep+xargs was Turing-complete, and now Claude is proving it.

Exactly. AGI implies minimal tooling and very primitive tools.

Re: The RAG Obituary: Killed by agents, buried by context windows

#42
This glosses over a fundamental scaling problem that undermines the entire argument. The author's main example is Claude Code searching through local codebases with grep and ripgrep, then extrapolates this to claim RAG is dead for all document retrieval. That's a massive logical leap.

Grep works great when you have thousands of files on a local filesystem that you can scan in milliseconds. But most enterprise RAG use cases involve millions of documents across distributed systems. Even with 2M token context windows, you can't fit an entire enterprise knowledge base into context. The author acknowledges this briefly ("might still use hybrid search") but then continues arguing RAG is obsolete.

The bigger issue is semantic understanding. Grep does exact keyword matching. If a user searches for "revenue growth drivers" and the document discusses "factors contributing to increased sales," grep returns nothing. This is the vocabulary mismatch problem that embeddings actually solve. The author spent half the article complaining about RAG's limitations with this exact scenario (his $5.1B litigation example), then proposes grep as the solution, which would perform even worse.

Also, the claim that "agentic search" replaces RAG is misleading. Recent research shows agentic RAG systems embed agents INTO the RAG pipeline to improve retrieval, they don't replace chunking and embeddings. LlamaIndex's "agentic retrieval" still uses vector databases and hybrid search, just with smarter routing.

Context windows are impressive, but they're not magic. The article reads like someone who solved a specific problem (code search) and declared victory over a much broader domain.

Re: The RAG Obituary: Killed by agents, buried by context windows

#45

This glosses over a fundamental scaling problem that undermines the entire argument. The author's main example is Claude Code searching through local codebases with grep and ripgrep, then extrapolates this to claim RAG is dead for all document retrieval. That's a massive logical leap. Grep works great when you have thousands of files on a local filesystem that you can scan in milliseconds. But most enterprise RAG use…

Agentic retrieval is really more a form of deep research (from a product standpoint there is very little difference). The key is that LLMs > rerankers, at least when you're not at webscale where the cost differential is prohibitive.

Re: The RAG Obituary: Killed by agents, buried by context windows

#46
post #39
post #36

Earlier quoted context omitted.

I’m sure that was your intent but why did you get bogged down talking about code?

hum because Claude Code pioneered the 'grep/glob/read' paradigm, so I felt the need to explain that what works well for coding files can also be applied to more complex documents.

Did you consider using words to explain that? I don’t think you pay yourself by the word.

Re: The RAG Obituary: Killed by agents, buried by context windows

#47

RAG isn't dead, RAG is just fiddly, you need to tune retrieval to the task. Also, grep is a form of RAG, it just doesn't use embeddings.

Yes my point is that the entire RAG pipeline like ingest, chunk, embed, search with Elastic, rerank is in decline. Grep is far simpler. It’s trivial.

Re: The RAG Obituary: Killed by agents, buried by context windows

#48
post #35
post #22

Earlier quoted context omitted.

How is this an ad? It's a couple thousand words about how they built something complicated that was then obsoleted.

in the same vein that a 'Behind The Scenes Look At The Making of Jurassic Park' is , in fact, an ad. having a company name pitched at you within the first two sentences is a pretty good give away.

3/4 of what hits the front page is an "ad" by that standard. I don't see how you can get less promotional than a long-form piece about why your tech is obsolete. Seems just mean-spirited.

Re: The RAG Obituary: Killed by agents, buried by context windows

#50

This glosses over a fundamental scaling problem that undermines the entire argument. The author's main example is Claude Code searching through local codebases with grep and ripgrep, then extrapolates this to claim RAG is dead for all document retrieval. That's a massive logical leap. Grep works great when you have thousands of files on a local filesystem that you can scan in milliseconds. But most enterprise RAG use…

Appreciate the feedback. I’m not saying grep replaces RAG. The shift is that bigger context windows let LLMs just read whole files, so you don’t need the whole chunk/embed pipeline anymore. Grep is just a quick way to filter down candidates.

From there the model can handle 100–200 full docs and jot notes into a markdown file to stay within context. That’s a very different workflow than classic RAG.

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