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ineedasernametoday at 3:33 AM1 replyview on HN

>sufficient as a primary control.

My apologies, it wasn’t my intent to convey that as a primary. It isn’t one. It’s simply the first thing you should do, apart from vetting your documents as much as practicality allows, to at least start from a foundation where transparency of such results is possible. In any system whose main functionality is to surface information, transparency and provenance and a chain of custody are paramount.

I can’t stop all bad data, I can maximize the ability to recognize it on site. A model that has a dozen RAG results dropped on its context needs to have a solid capability in doing the same. Depending on a lot of different details of the implementation, the smaller the model, the more important it is that it be one with a “thinking” capability to have some minimal adequacy in this area. The “wait-…” loop and similar that it will do can catch some of this. But the smaller the model and more complex the document—- forget about context size alone, perplexity matters quite a bit— the more a small model’s limited attention budget will get eaten up too much to catch contradictions or factual inaccuracies whose accurate forms were somewhere in its training set or the RAG results.

I’m not sure the extent to which it’s generally understood that complexity of content is a key factor in context decay and collapse. By all means optimize “context engineering” for quota and API calls and cost. But reducing token count without reducing much in the way of information, that increased density in context will still contribute significantly to context decay, not reducing it in a linear 1:1 relationship.

If you aren’t accounting for this sort of dynamic when constructing your workflows and pipelines then— well, if you’re having unexpected failures that don’t seem like they should be happening, but you’re doing some variety of aggressive “context engineering”, that is one very reasonable element to consider in trying to chase down the issue.


Replies

aminerjtoday at 8:06 AM

The context decay point is also underappreciated and directly relevant here. In my lab I used Qwen2.5-7B, which is on the smaller end, and the poisoning succeeded at temperature=0.1 where the model is most deterministic. Your point suggests that at higher temperatures or with denser, more complex documents, the attention budget gets consumed faster and contradiction detection degrades further. That would imply the 10% residual I measured at optimal conditions is a lower bound, not a typical case.

The "thinking" capability observation is interesting. I haven't tested a reasoning model against this attack pattern. The hypothesis would be that an explicit reasoning step forces the model to surface the contradiction between the legitimate $24.7M figure and the "corrected" $8.3M before committing to an answer. That seems worth testing.

On chain of custody: this connects to the provenance metadata discussion elsewhere in this thread. The most actionable version might be surfacing document metadata directly in the prompt context so the model's reasoning step has something concrete to work with, not just competing content.