> when the model won't actually be able to provide one
This is key. In my experience, asking an LLM why it did something is usually pointless. In a subsequent round, it generally can't meaningfully introspect on its prior internal state, so it's just referring to the session transcript and extrapolating a plausible sounding answer based on its training data of how LLMs typically work.
That doesn't necessarily mean the reply is wrong because, as usual, a statistically plausible sounding answer sometimes also happens to be correct, but it has no fundamental truth value. I've gotten equally plausible answers just pasting the same session transcript into another LLM and asking why it did that.
From early GPT days to now, best way to get a decently scoped and reasonably grounded response has always been to ask at least twice (early days often 7 or 8 times).
Because not only can it not reflect, it cannot "think ahead about what it needs to say and change its mind". It "thinks" out loud (as some people seem to as well).
It is a "continuation" of context. When you ask what it did, it still doesn't think, it just* continues from a place of having more context to continue from.
The game has always been: stuff context better => continue better.
Humans were bad at doing this. For example, asking it for synthesis with explanation instead of, say, asking for explanation, then synthesis.
You can get today's behaviors by treating "adaptive thinking" like a token budgeted loop for context stuffing, so eventually there's enough context in view to produce a hopefully better contextualized continuation from.
It seems no accident we've hit on the word "harness" — so much that seems impressive by end of 2025 was available by end of 2023 if "holding it right". If (and only if!) you are an expert in an area you need it to process: (1) turn thinking off, (2) do your own prompting to "prefill context", and (3) you will get superior final response. Not vibing, just staff-work.
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* “just” – I don't mean "just" dismissively. Qwen 3.5 and Gemma 4 on M5 approaches where SOTA was a year ago, but faster and on your lap. These things are stunning, and the continuations are extraordinary. But still: Garbage in, garbage out; gems in, gem out.
> In a subsequent round, it generally can't meaningfully introspect on its prior internal state
It can't do any better in the moment it's making the choices. Introspection mostly amounts to back-rationalisation, just like in humans. Though for humans, doing so may help learning to make better future decisions in similar situations.
I don't understand why people don't just say "This is wrong. try again." or "This is wrong because xyz. try again." This anthropologizing by asking why seems a bit pointless when you know how LLMs work, unless you've empirically had better results from a specific make and version of LLM by asking why in the past. It's theoretically functionally equivalent to asking a brand new LLM instance with your chat history why the original gave such an answer...Do you want the correct result or do you actually care about knowing why?
>Introspection mostly amounts to back-rationalisation, just like in humans.
That's the best case scenario. Again, let's stop anthropologizing. The given reasons why may be incompatible with the original answer upon closer inspection...
I definitely do this, along with the compulsion sometimes to tell the agent how a problem was fixed in the end, when investigating myself after the model failing to do so. Just common courtesy after working on something together. Let’s rationalize this as giving me an opportunity to reflect and rubberduck the solution.
Regarding not just telling „try again“: of course you are right to suggest that applying human cognition mechanisms to llm is not founded on the same underlying effects.
But due to the nature of training and finetuning/rf I don’t think it is unreasonable that instructing to do backwards reflection could have a positive effect. The model might pattern match this with and then exhibit a few positive behaviors. It could lead it doing more reflection within the reasoning blocks and catch errors before answering, which is what you want. These will have attention to the question of „what caused you to make this assumption“, also, encouraging this behavior. Yes, both mechanisms are exhibited through linear forward going statical interpolation, but the concept of reasoning has proven that this is an effective strategy to arrive at a more grounded result than answering right away.
Lastly, back to anthro. it shows that you, the user, is encouraging of deeper thought an self corrections. The model does not have psychological safety mechanisms which it guards, but again, the way the models are trained causes them to emulate them. The RF primes the model for certain behavior, I.e. arriving at answer at somepoint, rather than thinking for a long time. I think it fair to assume that by „setting the stage“ it is possible to influence what parts of the RL activate.
While role-based prompting is not that important anymore, I think the system prompts of the big coding agents still have it, suggesting some, if slight advantage, of putting the model in the right frame of mind. Again, very sorry for that last part, but anthro. does seem to be a useful analogy for a lot of concepts we are seeing (the reason for this being in the more far of epistemological and philosophical regions, both on the side of the models and us)
> This is key. In my experience, asking an LLM why it did something is usually pointless. In a subsequent round, it generally can't meaningfully introspect on its prior internal state, so it's just referring to the session transcript and extrapolating a plausible sounding answer based on its training data of how LLMs typically work.
Yep, I've gotten used to treating the model output as a finished, self-contained thing.
If it needs to be explained, the model will be good at that, if it has an issue, the model will be good at fixing it (and possibly patching any instructions to prevent it in the future). I'm not getting out the actual reason why things happened a certain way, but then again, it's just a token prediction machine and if there's something wrong with my prompt that's not immediately obvious and perhaps doesn't matter that much, I can just run a few sub-agents in a review role and also look for a consensus on any problems that might be found, for the model to then fix.
This can work, but it's sort of not the same as providing actual reasoning behind "why did you do/say X?" -- this is basically asking them model to read the conversation, from the conversation try to understand "why" something happened, and add information to prevent it from being wrong next time. That "why" something went wrong is not really the same as "why" the model output something.
> This is key. In my experience, asking an LLM why it did something is usually pointless.
That kind of strikes me as a huge problem. Working backwards from solutions (both correct and wrong) can yield pretty critical information and learning opportunities. Otherwise you’re just veering into “guess and check” territory.
The K/V Cache is just an optimization. But yeah you would expect the attention for the model producing "Ok im doing X" and you asking "Why did you do X?" be similar. So i don't see a reason why introspection would be impossible. In fact trying to adapt a test skill where the agent would write a new test instead of adapting a new one i asked it why and it gave the reasoning it used. We then adapted the skill to specifically reject that reasoning and then it worked and the agent adapted the existing test instead.
This is key. In my experience, asking an LLM why it did something is usually pointless. In a subsequent round, it generally can't meaningfully introspect on its prior internal state, so it's just referring to the session transcript and extrapolating a plausible sounding answer based on its training data of how LLMs typically work.
That doesn't necessarily mean the reply is wrong because, as usual, a statistically plausible sounding answer sometimes also happens to be correct, but it has no fundamental truth value. I've gotten equally plausible answers just pasting the same session transcript into another LLM and asking why it did that.