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

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

#11

This very much aligns with my experience — I had a case yesterday where opus was trying to do something with a library, and it encountered a build error. Rather than fix the error, it decided to switch to another library. It then encountered another error and decided to switch back to the first library. I don’t think I’ve encountered a case where I’ve just let the LLM churn for more than a few minutes and gotten a go…

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

#12

This very much aligns with my experience — I had a case yesterday where opus was trying to do something with a library, and it encountered a build error. Rather than fix the error, it decided to switch to another library. It then encountered another error and decided to switch back to the first library. I don’t think I’ve encountered a case where I’ve just let the LLM churn for more than a few minutes and gotten a go…

when this happens I do thew following 1) switch to a more expensive llm and ask it to debug: add debugging statements, reason about what's going on, try small tasks, etc 2) find issue 3) ask it to summarize what was wrong and what to do differently next time 4) copy and paste that recommendation to a small text document 5) revert to the original state and ask the llm to make the change with the recommendation as cont…

This honestly sounds slower than just doing it myself, and with more potential for bugs or non-standard code.

I've had the same experience as parent where LLMs are great for simple tasks but still fall down surprisingly quickly on anything complex and sometimes make simple problems complex. Just a few days ago I asked Claude how to do something with a library and rather than give me the simple answer it suggested I rewrite a large chunk of that library instead, in a way that I highly doubt was bug-free. Fortunately I figured there would be a much simpler answer but mistakes like that could easily slip through.

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

#13
This was always my mental model. If you have a process with N steps where your probability of getting a step right is p, your chance of success is pᶰ, or 0 as N → ∞.

It affects people too. Something I learned halfway through a theoretical physics PhD in the 1990s was that a 50-page paper with a complex calculation almost certainly had a serious mistake in it that you'd find if you went over it line-by-line.

I thought I could counter that by building a set of unit tests and integration tests around the calculation and on one level that worked, but in the end my calculation never got published outside my thesis because our formulation of the problem turned a topological circle into a helix and we had no idea how to compute the associated topological factor.

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

#14

This very much aligns with my experience — I had a case yesterday where opus was trying to do something with a library, and it encountered a build error. Rather than fix the error, it decided to switch to another library. It then encountered another error and decided to switch back to the first library. I don’t think I’ve encountered a case where I’ve just let the LLM churn for more than a few minutes and gotten a go…

> If it doesn’t solve an issue on the first or second pass, it seems to rapidly start making things up, make totally unrelated changes claiming they’ll fix the issue, or trying the same thing over and over. Sounds like a lot of employees I know. Changing out the entire library is quite amusing, though. Just imagine: I couldn't fix this build error, so I migrated our entire database from Postgres to MongoDB...

Thanks for the laughs.

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

#15

This very much aligns with my experience — I had a case yesterday where opus was trying to do something with a library, and it encountered a build error. Rather than fix the error, it decided to switch to another library. It then encountered another error and decided to switch back to the first library. I don’t think I’ve encountered a case where I’ve just let the LLM churn for more than a few minutes and gotten a go…

I've actually thought about this extensively, and experimented with various approaches. What I found is that the quality of results I get, and whether the AI gets stuck in the type of loop you describe, depends on two things: how detailed and thorough I am with what I tell it to do, and how robust the guard rails I put around it are. To get the best results, I make sure to give detailed specs of both the current situ…

But don't they keep forgetting the instructions after enough time have passed? How do you get around that? Do you add an instruction that after every action it should go back and read the instructions gain?

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

#16

This very much aligns with my experience — I had a case yesterday where opus was trying to do something with a library, and it encountered a build error. Rather than fix the error, it decided to switch to another library. It then encountered another error and decided to switch back to the first library. I don’t think I’ve encountered a case where I’ve just let the LLM churn for more than a few minutes and gotten a go…

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 poisonous tokens.

Right now I work around it by regularly making summaries of instances, and then spinning up a new instance with fresh context and feed in the summary of the previous instance.

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

#18

This very much aligns with my experience — I had a case yesterday where opus was trying to do something with a library, and it encountered a build error. Rather than fix the error, it decided to switch to another library. It then encountered another error and decided to switch back to the first library. I don’t think I’ve encountered a case where I’ve just let the LLM churn for more than a few minutes and gotten a go…

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 course.

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

#19

This very much aligns with my experience — I had a case yesterday where opus was trying to do something with a library, and it encountered a build error. Rather than fix the error, it decided to switch to another library. It then encountered another error and decided to switch back to the first library. I don’t think I’ve encountered a case where I’ve just let the LLM churn for more than a few minutes and gotten a go…

> If it doesn’t solve an issue on the first or second pass, it seems to rapidly start making things up, make totally unrelated changes claiming they’ll fix the issue, or trying the same thing over and over. Sounds like a lot of employees I know. Changing out the entire library is quite amusing, though. Just imagine: I couldn't fix this build error, so I migrated our entire database from Postgres to MongoDB...

It may be doing the wrong thing like an employee, but at least it's doing it automatically and faster. :)
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