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Is there a half-life for the success rates of AI agents?

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111–120 of 143 posts

Re: Is there a half-life for the success rates of AI agents?

#111
post #92
post #35

Earlier quoted context omitted.

If humans can say "The proof is left as an exercise for the reader", why can't LLMs :)

If I'm paying someone to solve a problem for me and they tell me part of it is left for me to sort out then I'm gonna be pretty unhappy with how I spent my money.

[deleted]

Re: Is there a half-life for the success rates of AI agents?

#112
post #110

Earlier quoted context omitted.

They poison their own context. Maybe you can call it context rot, where as context grows and especially if it grows with lots of distractions and dead ends, the output quality falls off rapidly. Even with good context the rot will start to become apparent around 100k tokens (with Gemini 2.5). They really need to figure out a way to delete or "forget" prior context, so the user or even the model can go back and prune…

I think you just coined "context rot", what an excellent term! Quoted you on my blog https://simonwillison.net/2025/Jun/18/context-rot/

I always referred it more as context degradation, but rot is more visceral.

Re: Is there a half-life for the success rates of AI agents?

#113
post #105

Earlier quoted context omitted.

Very common to see in comments some people saying “it can’t do that” and others saying “here is how I make it work.” Maybe there is a knack to it, sure, but I’m inclined to say the difference between the problems people are trying to use it on may explain a lot of the difference as well. People are not usually being too specific about what they were trying to do. The same goes for a lot of programming discussion of c…

I ask it to build it to 3d voxel engine in Rust, and it just goes off and do it. Same for a vox file parser. Sure, it takes some creative prompting, and a lot of turns to get it to settle on the proper coordinate system for the whole thing, but it goes ahead and does it. This took me two days so far. Unfortunate, the scope of the thing is now so large that the quality rapidly starts to degrade.

Building something from scratch where there are plenty of examples public on github seems to be the easiest case. Put these agents on a real existing codebase and ask them to fix a bug and they become useless.

Re: Is there a half-life for the success rates of AI agents?

#114

Earlier quoted context omitted.

They poison their own context. Maybe you can call it context rot, where as context grows and especially if it grows with lots of distractions and dead ends, the output quality falls off rapidly. Even with good context the rot will start to become apparent around 100k tokens (with Gemini 2.5). They really need to figure out a way to delete or "forget" prior context, so the user or even the model can go back and prune…

> They really need to figure out a way to delete or "forget" prior context This is already pretty much figured out: https://www.promptingguide.ai/techniques/react We use it at work and we never encounter this kind of issues.

How does ReAct address this? Unless one of the actions is deleting part of the message history...

Re: Is there a half-life for the success rates of AI agents?

#115
post #110

Earlier quoted context omitted.

They poison their own context. Maybe you can call it context rot, where as context grows and especially if it grows with lots of distractions and dead ends, the output quality falls off rapidly. Even with good context the rot will start to become apparent around 100k tokens (with Gemini 2.5). They really need to figure out a way to delete or "forget" prior context, so the user or even the model can go back and prune…

I think you just coined "context rot", what an excellent term! Quoted you on my blog https://simonwillison.net/2025/Jun/18/context-rot/

I don’t know why, but going out of your way to make sure the coining of this is attributed to a random user on the internet made me incredibly nostalgic for what the pre Web 2.0 internet was like sans the 4chans, liveleak, and their forebears on usenet

Re: Is there a half-life for the success rates of AI agents?

#116
post #110

Earlier quoted context omitted.

They poison their own context. Maybe you can call it context rot, where as context grows and especially if it grows with lots of distractions and dead ends, the output quality falls off rapidly. Even with good context the rot will start to become apparent around 100k tokens (with Gemini 2.5). They really need to figure out a way to delete or "forget" prior context, so the user or even the model can go back and prune…

I think you just coined "context rot", what an excellent term! Quoted you on my blog https://simonwillison.net/2025/Jun/18/context-rot/

History in the making

Re: Is there a half-life for the success rates of AI agents?

#117

Earlier quoted context omitted.

They poison their own context. Maybe you can call it context rot, where as context grows and especially if it grows with lots of distractions and dead ends, the output quality falls off rapidly. Even with good context the rot will start to become apparent around 100k tokens (with Gemini 2.5). They really need to figure out a way to delete or "forget" prior context, so the user or even the model can go back and prune…

I feel like as an end user I’d like to be able to do more to shape the LLM behavior. For example, I’d like to flag the dead end paths so they’re properly dropped out of context and not explored again, unless I as a user clear the flag(s). I know there is work being done on LLM “memory” for lack of a better term but I have yet to see models get more responsive over time with this kind of feedback. I know I can flag it…

Any good chat client will let you not only modify previous messages in place, but also modify the LLM responses, and regenerate from any point.

Re: Is there a half-life for the success rates of AI agents?

#118

Earlier quoted context omitted.

There are just certain problems that they cannot solve. Usually when there is no clear example in its pretraining or discoverable on the net. I would say the reasoning capabilities of these models are pretty shallow, at least it seems that way to me

They can't reason at all. The language specification for Tcl 9 is in the training data of the SOTA models but there exist almost no examples, only documentation. Go ahead, try to get a model to write Tcl 9 instead of 8.5 code and see for yourself. They can't do it, at all. They write 8.5 exclusively, because they only copy. They don't reason. "reasoning" in LLMs is pure marketing.

It becomes clear that it's just statistics once you get near a statistically significant "attractor".

A silly example is any of the riddles where you just simplify it to an obvious degree and the LLM can't get it (mostly gone with recent big models), like: "A man, a sheep, and a boat need to get across a river. How can they do this safely without the sheep being eaten".

A more practically infuriating example is when you want to do something slightly different than a very common problem. The LLM might eventually get it right, after too much guidance, but then it'll slowly revert back to the "common" case. For example, replacing whole chunks of code with whatever common thing when you tell it add comments. This happens frequently to me with super basic vector math.

Re: Is there a half-life for the success rates of AI agents?

#119
post #105

Earlier quoted context omitted.

I ask it to build it to 3d voxel engine in Rust, and it just goes off and do it. Same for a vox file parser. Sure, it takes some creative prompting, and a lot of turns to get it to settle on the proper coordinate system for the whole thing, but it goes ahead and does it. This took me two days so far. Unfortunate, the scope of the thing is now so large that the quality rapidly starts to degrade.

Building something from scratch where there are plenty of examples public on github seems to be the easiest case. Put these agents on a real existing codebase and ask them to fix a bug and they become useless.

I think this would vary a lot between "real" code basis. I have had a lot of success when using somewhat stricter frameworks, with typed interfaces, and requiring well defined unit tests, and modules which ecapsulate a lot of logic.

Basically like Java Spring Boot or NestJS type projects.

Re: Is there a half-life for the success rates of AI agents?

#120

Earlier quoted context omitted.

They poison their own context. Maybe you can call it context rot, where as context grows and especially if it grows with lots of distractions and dead ends, the output quality falls off rapidly. Even with good context the rot will start to become apparent around 100k tokens (with Gemini 2.5). They really need to figure out a way to delete or "forget" prior context, so the user or even the model can go back and prune…

I feel like as an end user I’d like to be able to do more to shape the LLM behavior. For example, I’d like to flag the dead end paths so they’re properly dropped out of context and not explored again, unless I as a user clear the flag(s). I know there is work being done on LLM “memory” for lack of a better term but I have yet to see models get more responsive over time with this kind of feedback. I know I can flag it…

At some point, shouldn't these things start understanding what they're doing ?
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