Prompt changes affect output substantially (just look up arxiv), the difficult part is find an optimal structure to yield the best results. It is a bit expensive to do a lot of testing on your own, so it all boils down to feels and experience at the moment. Then you mix up tool calls, other agent calls, client functions and this gets terribly hard to evaluate.
I am still puzzled how distance between policies can have an effect on the output. And how a simple retry fixes everything.
Here is the summary of key improvements made:
1. Structure & Flow
- Decision Trees: Clear branching logic with ├── and └── notation
- Sequential Steps: Numbered, ordered procedures instead of scattered explanations
- Prerequisites: Explicit dependency checks before proceeding
2. AI Agent Optimizations
- Tool Call Clarity: Exact function names and parameters
- Binary Decisions: Clear yes/no conditions instead of ambiguous language
- Error Handling: Specific failure conditions and next steps
- Verification Steps: "Recheck" instructions after each fix
3. Cognitive Load Reduction
- Reference Tables: Quick lookup for tools and purposes
- Pattern Recognition: Common issue combinations and their solutions
- Critical Reminders: Common AI mistakes section to prevent errors
4. Actionable Language
- Removed verbose explanations mixed with instructions
- Consolidated multiple documents' logic into single workflows
- Used imperative commands: "Check X", "If Y then Z"
- Added immediate verification steps
I’ve found myself writing code intending to write prompts for writing better code.
Soon enough Im sure we’ll start to see programming languages that are geared towards interacting with llms
In other words, just like programming, we’re writing better instructions. In this case, we’re asking it to think out loud more clearly. It’s almost like whiteboard interview prep.
It’s quite amazing because it means programming is fully entering the natural language phase of the timeline.
If you aren’t a solid clear writer, you may not make it in the brave new world.
>If you aren’t a solid clear writer, you may not make it in the brave new world.
Have you not heard of all the AI startups that can turn a 3-word thought into very clearly written prose to be lovingly poured into the waiting mouth of your AI agent?
Isn’t programming the clearest form of writing? Perhaps it’s the non programmers that need to “catch up”.
We are still in the pigsty compared to math
I'd have to disagree. We're much less ambiguous than math.
In fact, according to theory, we're writing executable proofs.
The computers of the future will be operated by shamans making incantations more than technicians writing code.
Of the future?
We already have people praying to the machine gods, so I guess your future is next week?
>GPT-5 showed significant improvement only in one benchmark domain - which is Telecom. The other ones have been somehow overlooked during model presentation - therefore we won’t bother about them either.
I work at OpenAI and you can partly blame me for our emphasis on Telecom. While we no doubt highlight the evals that make us look good, let me defend why the emphasis on Telecom isn't unprincipled cherry picking.
Telecom was made after Retail and Airline, and fixes some of their problems. In Retail and Airline, the model is graded against a ground truth reference solution. Grading against a reference solution makes grading easier, but has the downside that valid alternative solutions can receive scores of 0 by the automatic grading. This, along with some user model issues, is partly why Airline and Retail scores stopped climbing with the latest generations of models and are stuck around 60% / 80%. I'd bet you $100 that a superintelligence would probably plateau around here too, as getting 100% requires perfect guessing of which valid solution is written as the reference solution.
In Telecom, the authors (Barres et al.) made the grading less brittle by grading against outcome states, which may be achieved via multiple solutions, rather than by matching against a single specific solution. They also improved the user modeling and some other things too. So Telecom is the much better eval, with a much cleaner signal, which is partly why models can score as high as 97% instead of getting mired at 60%/80% due to brittle grading and other issues.
Even if I had never seen GPT-5's numbers, I like to think I would have said ahead of time that Telecom is much better than Airline/Retail for measuring tool use.
Incidentally, another thing to keep in mind when critically looking at OpenAI and others reporting their scores on these evals is that the evals give no partial credit - so sometimes you can have very good models that do all but one thing perfectly, which results in very poor scores. If you tried generalizing to tasks that don't trigger that quirk, you might get much better performance than the eval scores suggest (or vice versa, if your tasks trigger a quirk not present in the eval).
Haha, I guess my little sarcasm just earned us a masterclass! Thanks a lot for sharing your insights — really appreciate it!
I wish they had published what prompt was given to Claude to improve GPT-5-mini's performance, as well as a before and after comparison of a prompt that underwent this transformation.
Thanks for the feedback, appreciate it!
It makes lot of sense - I'll update the article with links to the actual prompts.
Initially I thought these would be too lengthy for the article and no one would care, but as it seems people are really interested in it. Of course I'd be happy to share the details.
I checked and also couldn't find the prompt.
I published an update - you should be able to find that information at the end of the post.
Should be available now, although it might take a while for CDN to propagate.
Thanks for sharing!
My take: we have no clue how this works and the performance can be down tomorrow just as well.
My hypothesis: the length of the prompt shrunk, yet maintained the same amount of information.
This is the PR with the changes in case people missed it:
Thanks! I also updated the post with the link on the website.
Rewriting prompts don't come with no costs. The cost here is that different prompts work for different contexts and is not generalisable. The rewritten prompt here will not work well for other cases like medical or social advice.
I think this rewriting of prompts technique is the reason "reasoning" models perform well - they know exactly how to rewrite the prompts for a context.
FWIW I don't trust these benchmarks fully because a huge bump like this is not expected - I would expect OpenAI to optimise enough to let such gaps open.
The only problem is I feel like having to have Claude rewrite the prompt negates some of the efficiency and latency benefits of using mini. For system prompts obviously this doesn't matter, but for actual continuous user interaction, it feels unworkable.
It definitely makes sense that improving formatting and clarity for these smaller models would really help with performance, but I'm wondering if gpt5-mini is already smart enough to handle that reformatting, and can rewrite the prompt itself, before handing it off to another instance of itself.
Overall an awesome article!
Really intresting. What did the original prompt look like? Perhaps the original prompt was not that good? I feel like the changes claude suggested (except a couple maybe) are already pretty well known prompt engineering practices.
Doesn't saying "check -> action" suggest you're taking _away_ the agentic capabilities, and optimizing for the benchmark, meaning it's no longer a good benchmark for agentic capabilities?
That's like being able to see the test before taking it
Copilot in VSCode seems to do something similar in the form of todo lists.
This sort of stuff is trodden ground, if this seems exciting to you check out DSPy.
Many of the "look at what I did programming LLMs" blog posts on Hacker News have been developed and put out in academic papers and groups. The posts which gain traction here seem to be perennially behind the state of the art.
> Removed verbose explanations mixed with instructions
Is Claude rewriting generic instructions once, or is it rewriting the core task statement each time? If so, I'm not sure how you prevent information leakage: Claude might easily be "solving" some of the tasks and inserting subtle hints on the approach. I think this result is very interesting if it holds after rewriting only the generic instructions, even if the performance boost is lower.
I wonder if it would be possible to improve even further on the benchmark by simply showing Claude the current hardest problems and asking it to improve the prompt without including any specifics related to the problems
Have you tried to use gpt-5 with high thinking to rewrite the prompt? why claude for this vs some other model?
No before/after prompt.
Into the trash it goes.
[deleted]
DSPy was ahead of its time and still underutilized.
Can you point me to any resources on DSPy that don't make it look like magic though? It used to be all the hype for a while and then everyone moved on from it.
Using an LLM to (re)write your prompt or system prompt (for local models) is free alpha.
My experience as well.
Prompt changes affect output substantially (just look up arxiv), the difficult part is find an optimal structure to yield the best results. It is a bit expensive to do a lot of testing on your own, so it all boils down to feels and experience at the moment. Then you mix up tool calls, other agent calls, client functions and this gets terribly hard to evaluate.
I am still puzzled how distance between policies can have an effect on the output. And how a simple retry fixes everything.
Here is the summary of key improvements made:
1. Structure & Flow
2. AI Agent Optimizations 3. Cognitive Load Reduction 4. Actionable LanguageI’ve found myself writing code intending to write prompts for writing better code.
Soon enough Im sure we’ll start to see programming languages that are geared towards interacting with llms
Finally a use for Lojban!
https://en.wikipedia.org/wiki/Lojban
Wait, are we about to reinvent programming from first principles?
Seemingly its always been on a scale between directly editing 1s and 0s and drafting legislature. Compile times may vary
I'd say it's more "programming with extra steps"
This is more like reinvention by trying everything which doesn't work first. It's the dual of first principles.
Maybe one day we will all be using https://shakespearelang.com/
In other words, just like programming, we’re writing better instructions. In this case, we’re asking it to think out loud more clearly. It’s almost like whiteboard interview prep.
It’s quite amazing because it means programming is fully entering the natural language phase of the timeline.
If you aren’t a solid clear writer, you may not make it in the brave new world.
>If you aren’t a solid clear writer, you may not make it in the brave new world.
Have you not heard of all the AI startups that can turn a 3-word thought into very clearly written prose to be lovingly poured into the waiting mouth of your AI agent?
Isn’t programming the clearest form of writing? Perhaps it’s the non programmers that need to “catch up”.
We are still in the pigsty compared to math
I'd have to disagree. We're much less ambiguous than math.
In fact, according to theory, we're writing executable proofs.
The computers of the future will be operated by shamans making incantations more than technicians writing code.
Of the future?
We already have people praying to the machine gods, so I guess your future is next week?
>GPT-5 showed significant improvement only in one benchmark domain - which is Telecom. The other ones have been somehow overlooked during model presentation - therefore we won’t bother about them either.
I work at OpenAI and you can partly blame me for our emphasis on Telecom. While we no doubt highlight the evals that make us look good, let me defend why the emphasis on Telecom isn't unprincipled cherry picking.
Telecom was made after Retail and Airline, and fixes some of their problems. In Retail and Airline, the model is graded against a ground truth reference solution. Grading against a reference solution makes grading easier, but has the downside that valid alternative solutions can receive scores of 0 by the automatic grading. This, along with some user model issues, is partly why Airline and Retail scores stopped climbing with the latest generations of models and are stuck around 60% / 80%. I'd bet you $100 that a superintelligence would probably plateau around here too, as getting 100% requires perfect guessing of which valid solution is written as the reference solution.
In Telecom, the authors (Barres et al.) made the grading less brittle by grading against outcome states, which may be achieved via multiple solutions, rather than by matching against a single specific solution. They also improved the user modeling and some other things too. So Telecom is the much better eval, with a much cleaner signal, which is partly why models can score as high as 97% instead of getting mired at 60%/80% due to brittle grading and other issues.
Even if I had never seen GPT-5's numbers, I like to think I would have said ahead of time that Telecom is much better than Airline/Retail for measuring tool use.
Incidentally, another thing to keep in mind when critically looking at OpenAI and others reporting their scores on these evals is that the evals give no partial credit - so sometimes you can have very good models that do all but one thing perfectly, which results in very poor scores. If you tried generalizing to tasks that don't trigger that quirk, you might get much better performance than the eval scores suggest (or vice versa, if your tasks trigger a quirk not present in the eval).
Here's the tau2-bench paper if anyone wants to read more: https://arxiv.org/abs/2506.07982
Haha, I guess my little sarcasm just earned us a masterclass! Thanks a lot for sharing your insights — really appreciate it!
I wish they had published what prompt was given to Claude to improve GPT-5-mini's performance, as well as a before and after comparison of a prompt that underwent this transformation.
Thanks for the feedback, appreciate it! It makes lot of sense - I'll update the article with links to the actual prompts. Initially I thought these would be too lengthy for the article and no one would care, but as it seems people are really interested in it. Of course I'd be happy to share the details.
I checked and also couldn't find the prompt.
I published an update - you should be able to find that information at the end of the post.
Should be available now, although it might take a while for CDN to propagate.
Thanks for sharing!
My take: we have no clue how this works and the performance can be down tomorrow just as well.
My hypothesis: the length of the prompt shrunk, yet maintained the same amount of information.
This is the PR with the changes in case people missed it:
https://github.com/mieciu/tau2-bench/pull/1/files
Thanks! I also updated the post with the link on the website.
Rewriting prompts don't come with no costs. The cost here is that different prompts work for different contexts and is not generalisable. The rewritten prompt here will not work well for other cases like medical or social advice.
I think this rewriting of prompts technique is the reason "reasoning" models perform well - they know exactly how to rewrite the prompts for a context.
FWIW I don't trust these benchmarks fully because a huge bump like this is not expected - I would expect OpenAI to optimise enough to let such gaps open.
The only problem is I feel like having to have Claude rewrite the prompt negates some of the efficiency and latency benefits of using mini. For system prompts obviously this doesn't matter, but for actual continuous user interaction, it feels unworkable.
It definitely makes sense that improving formatting and clarity for these smaller models would really help with performance, but I'm wondering if gpt5-mini is already smart enough to handle that reformatting, and can rewrite the prompt itself, before handing it off to another instance of itself.
Overall an awesome article!
Really intresting. What did the original prompt look like? Perhaps the original prompt was not that good? I feel like the changes claude suggested (except a couple maybe) are already pretty well known prompt engineering practices.
Thank you for the feedback!
In this (telecom) benchmark you can review agent policies and manuals here: 1) https://github.com/sierra-research/tau2-bench/blob/main/data... 2) https://github.com/sierra-research/tau2-bench/blob/main/data...
Of course these are just parts of the prompt, you can inspect benchamark code to see how these are rendered to actual LLM calls.
In case someone is not familiar with framework methodology I've wrote a separate article covering that (with some of my thoughts) -> https://quesma.com/blog/tau2-from-llm-benchmark-to-blueprint...
Doesn't saying "check -> action" suggest you're taking _away_ the agentic capabilities, and optimizing for the benchmark, meaning it's no longer a good benchmark for agentic capabilities?
That's like being able to see the test before taking it
Copilot in VSCode seems to do something similar in the form of todo lists.
This sort of stuff is trodden ground, if this seems exciting to you check out DSPy.
Many of the "look at what I did programming LLMs" blog posts on Hacker News have been developed and put out in academic papers and groups. The posts which gain traction here seem to be perennially behind the state of the art.
https://dspy.ai/tutorials/tool_use/
Definitely interesting, thank you!
> Removed verbose explanations mixed with instructions
Is Claude rewriting generic instructions once, or is it rewriting the core task statement each time? If so, I'm not sure how you prevent information leakage: Claude might easily be "solving" some of the tasks and inserting subtle hints on the approach. I think this result is very interesting if it holds after rewriting only the generic instructions, even if the performance boost is lower.
I wonder if it would be possible to improve even further on the benchmark by simply showing Claude the current hardest problems and asking it to improve the prompt without including any specifics related to the problems
Have you tried to use gpt-5 with high thinking to rewrite the prompt? why claude for this vs some other model?
No before/after prompt.
Into the trash it goes.
DSPy was ahead of its time and still underutilized.
Can you point me to any resources on DSPy that don't make it look like magic though? It used to be all the hype for a while and then everyone moved on from it.
Using an LLM to (re)write your prompt or system prompt (for local models) is free alpha.
you would also be interested in dSPY...
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