Ingesting PDFs and why Gemini 2.0 changes everything

I work in fintech and we replaced an OCR vendor with Gemini at work for ingesting some PDFs. After trial and error with different models Gemini won because it was so darn easy to use and it worked with minimal effort. I think one shouldn't underestimate that multi-modal, large context window model in terms of ease-of-use. Ironically this vendor is the best known and most successful vendor for OCR'ing this specific type of PDF but many of our requests failed over to their human-in-the-loop process. Despite it not being their specialization switching to Gemini was a no-brainer after our testing. Processing time went from something like 12 minutes on average to 6s on average, accuracy was like 96% of that of the vendor and price was significantly cheaper. For the 4% inaccuracies a lot of them are things like the text "LLC" handwritten would get OCR'd as "IIC" which I would say is somewhat "fair". We probably could improve our prompt to clean up this data even further. Our prompt is currently very simple: "OCR this PDF into this format as specified by this json schema" and didn't require some fancy "prompt engineering" to contort out a result.

Gemini developer experience was stupidly easy. Easy to add a file "part" to a prompt. Easy to focus on the main problem with weirdly high context window. Multi-modal so it handles a lot of issues for you (PDF image vs. PDF with data), etc. I can recommend it for the use case presented in this blog (ignoring the bounding boxes part)!

This is spot on, any legacy vendor focusing on a specific type of PDF is going to get obliterated by LLMs. The problem with using an off-the-shelf provider like this is, you get stuck with their data schema. With an LLM, you have full control over the schema meaning you can parse and extract much more unique data.

The problem then shifts from "can we extract this data from the PDF" to "how do we teach an LLM to extract the data we need, validate its performance, and deploy it with confidence into prod?"

You could improve your accuracy further by adding some chain-of-thought to your prompt btw. e.g. Make each field in your json schema have a `reasoning` field beforehand so the model can CoT how it got to its answer. If you want to take it to the next level, `citations` in our experience also improves performance (and when combined with bounding boxes, is powerful for human-in-the-loop tooling).

Disclaimer: I started an LLM doc processing infra company (https://extend.app/)