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RAG Is Simpler Than You Think

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Re: RAG Is Simpler Than You Think

#21

Here’s an even simpler take: just embed everything the first time, then track what was changed. Use a cheap model to summarize and clean up the documents/chats with summary and keywords. Unless you have entire libraries of books to embed it’s going to be a few hundred dollars of API calls. Then, throw it all in BigQuery. Handles all the vector stuff natively. Sprinkle an agentic bot UI thing on top to make it appear…

Yep, lock into some vendor from day 1. Great idea!

Re: RAG Is Simpler Than You Think

#22

The article sounds like AI slop with some predictable tells like short punctual sentences, bizarre jargon, and titles like "Recipe 4: On-The-Fly Embedding (The Fresh Data Play)" Can we not reward junk like this? Most of the sentences are incomprehensible and provide zero actual argumentation, it's just a list of "whats" with no "whys"

You are right, now I noticed "Real talk" and "Why this is underrated" and I can't unsee it.

Re: RAG Is Simpler Than You Think

#23

Here’s an even simpler take: just embed everything the first time, then track what was changed. Use a cheap model to summarize and clean up the documents/chats with summary and keywords. Unless you have entire libraries of books to embed it’s going to be a few hundred dollars of API calls. Then, throw it all in BigQuery. Handles all the vector stuff natively. Sprinkle an agentic bot UI thing on top to make it appear…

Yep, lock into some vendor from day 1. Great idea!

Vendor lock in is 2025. Porting became trivial with LLMs advancing like they have.

Re: RAG Is Simpler Than You Think

#24
post #11
post #4

Maybe I'm old but where exactly are the "dragons"? How is RAG any different from the search systems we've been building before LLMs? Is it the sudden need for everyone to design a search API and engine that's driven this trend? If so, I'd like to see more design patterns around existing search problems: - Correcting or backtracking based on feedback. - Measuring relevance. - Comparison with task-based pre-written que…

The whole embedding thing which converts “tokens” to vectors, which you then store in a vector database so that you can later query by vector distance, seems to be LLM specific technology, no? As far as I know the vectors look a lot like the weights in a LLM itself which is why the vector search also works with some level of intelligence.

not really, vectorising text/books is old school ML by this point.

at least to me that seems the same as https://en.wikipedia.org/wiki/Word2vec for e.g.

Re: RAG Is Simpler Than You Think

#25

I have a particular antipathy for articles too lazy to spell out acronyms on first use. So: https://en.wikipedia.org/wiki/Retrieval-augmented_generation

The audience for this piece is already very familiar with RAG. I don't want articles discussing e.g. OLED screens telling me what the acronym is - that would be a sign that the article is far below the level that I need.

Re: RAG Is Simpler Than You Think

#26

OT but its interesting that none of the harnesses today use embeddings but just simple grep. I would not have predicted this

Ok? I'm not seeing how that is interesting, you're exclusively focusing on coding which requires precise substring locations. Google is basically almost entirely driven by embedding models now.

Re: RAG Is Simpler Than You Think

#27
I worked on large scale RAG systems before and can say people vastly underestimate full text search and vastly overestimate embeddings. FTS is really easy, portable and scalable and gets you very far, the 80/20 rule applies. Embeddings appear to be nice and magic but when you really get into them you notice: semantic similarity isn’t as good as you think and certainly it won’t make everyone happy. You will inevitably end up having to re-embed more or different chunks of your text to accommodate more and more precise embedding search - at which point you’ll go the last mile and do reranking etc etc all the while having to support the operational burden of vector search. Then you turn around and build a search query with 500 keywords and sure it’s painful but it just works, accommodates all use cases, scales and is overall less annoying to maintain.

Re: RAG Is Simpler Than You Think

#28
post #2

There have been many blogs like this over the last years. Yes, embeddings are computationally heavy, but they are not at all complicated and they provide a lot of benefit. 90% of "document" based RAG projects should view semantic search with embeddings as their primary method. It's very powerful and so easy to implement that you could try it out and discover whether performance would be an issue rather than trying to…

Embeddings are reasonably simple, but it’s a journey to get there, and I am very proud of the dog-heavy explainer I wrote on them: https://sgnt.ai/p/embeddings-explainer/

This is terrific, thank you! There's a typo in the following sentence:

  > we don’t especially want to say that books on forestry and similar to books on puppies
^and^are

Re: RAG Is Simpler Than You Think

#29

Here’s an even simpler take: just embed everything the first time, then track what was changed. Use a cheap model to summarize and clean up the documents/chats with summary and keywords. Unless you have entire libraries of books to embed it’s going to be a few hundred dollars of API calls. Then, throw it all in BigQuery. Handles all the vector stuff natively. Sprinkle an agentic bot UI thing on top to make it appear…

> embed everything the first time

This assumes your text is small. Try embedding pdf reports - though luck. It surely won’t fit into most embeddings. I can think of many more examples: books, news articles, medical reports, insurance claims etc. they’re all too big to “index it all at once”

Re: RAG Is Simpler Than You Think

#30

I worked on large scale RAG systems before and can say people vastly underestimate full text search and vastly overestimate embeddings. FTS is really easy, portable and scalable and gets you very far, the 80/20 rule applies. Embeddings appear to be nice and magic but when you really get into them you notice: semantic similarity isn’t as good as you think and certainly it won’t make everyone happy. You will inevitably…

I thought text search was always the first thing you try, then fuzzy search, then you go for RAG
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