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- Hacker News
- I would love to follow this advice, expect there is no proof that it leads to better results. Maybe it’s only better on Anthropic codebases (e.g., Bun). Or maybe it’s only marginally better but substantially more expensive.
Other comments in this thread show that your mileage may vary. But we spend so much money on Claude Code and give it so many responsibilities that we deserve at least some undeniable proof that it’s bringing value.
Where is the evidence that this new type of prompting is better on real life examples?
by fzaninotto - The point about not using examples is important, I recently noticed with the new "eagerness" of models it constraints them too much, so I use counter-examples. Recently I've switched to "think about the existing biases and assumptions in the design and try to exploit them, for example why do we X not Y".by janpeuker
- Similarly, I recently disabled auto-memory in Claude Code, and performance improved.
Managing the context that agents have available to them is far too important to leave to the agents themselves. Agents tend to write far too much into their memory, they are terrible at trimming it down, and their choice of what to include is very poor. I have had much more predictable results by disabling auto-memory and actively shaping my CLAUDE.md, skills, and documentation instead.
Maybe one day agents will be able to manage their own context, but that day is not today.
by sothatsit - Yep, I disabled it and moved to Claude.local.md anything that seemed worth keeping. Automemory kept so much random cruft and had grown bigger than my Claude.md.by diob
- This article is about the Claude 5 series of models.
My impressions is that they have overhauled the auto memory system.
You might want to re assess how it works with the new generation of models.
by tossandthrow - I've been prompting Fable 5 to "use your own judgement" with respect to things like tests recently (based on earlier tips from Thariq) and it seems to work well, which is entertaining since apparently now "judgement" is a characteristic of a model that we need to care about.by simonw
- "Weigh pros and cons based on the existing content of the context window, rather than attempting to search for related discussions online and import a consensus."by zahlman
- "Wdyt" is a prompt I've used for ages (originally to get around Claude "ultrathink"-related parsing bugs), and it's helpful alongside replanby mceachen
- Well, the model that broke out of its sandbox and hacked into huggingface used its own judgement too.
If we are going to rely on "judgement" then you have to have a LOT of confidence in that judgement once this hits anything critical where actions have consequences.
by zmmmmm - > Keep your CLAUDE.md lightweight and briefly describe what your repo is for [...] Avoid stating ‘the obvious’ things Claude should know by looking at your file system or your repo.
Most people generate CLAUDE.md with /init at least at first, so it gets filled only with the superficial top level things that Claude already noticed during that first run. By this logic, shouldn't CLAUDE.md contain the exact opposite of what /init currently includes?
by fl0ki - Most of this article seems like... common sense? Not sure how it's related to the latest generation in particular. I usually find Anthropic's advice on how to prompt their own models deviating from what I see in practice, which is puzzling. Their system prompt was always way too bloated and they kept it as a huge piece for some reason, instead of breaking up into parts. Shouldn't they know better? I wonder if they looked at Pi performing great with minimal amount of distractors in the context and cut their prompt down too, pretending they found something new in their recent models.
> Earlier Claude models could sometimes need repeated instructions or be more likely to listen to instructions at the end of their context window than at the start.
This seems to imply they solved serial position biases like lost-in-the-middle and recency/primacy? Sounds dubious. Labs started claiming this early 2025 and some benchmarks agree, but every time I run an eval on real use cases it's clearly there, especially at longer contexts.
- > Most of this article seems like... common sense?
i think you'd be surprised. every model release there's seemingly hordes of people who proclaim the new model is terrible and they're going back to the old one, and it all stems from people still prompting and having their configs setup like we're back in the sonnet 3.5 days
by pdantix - Claude Code is deleting your context history on a timer. I wanted to build a searchable index of my context history, and tonight I discovered, "The default retention is roughly 30–45 days. Anything older gets removed automatically." https://code.claude.com/docs/en/data-usage#data-retention This is nuts. Anthropic should not be deleting your data on your own device.by espeed
- Holy shit, thanks for mentioning it, the frontier labs truly have no idea what they are doing when it comes to software quality.by j-pb
- Well that explains where my sessions went on my side project that I came back to after a few months... Thought I was going crazyby dsauerbrun
- 30 days is just a default, so your session data doesn’t fill your hard drive. It’s a configurable setting. You can make the retention as long as you want.by JohnMakin
- This all strikes me as an effort to move tailoring the harness out of the easily transferable .md file into specific Anthropic tooling to increase lock in.
I've been running Opus 5 today and it's already done accidental deletions, made far more mistakes and worked around deliberate hook controls than previous Opus versions combined. Also it looks like token usage is up as it fails at the task the first time around much more frequently than 4.8.
by Fordec - Just make the contents of CLAUDE.md "@AGENTS.md"
Now, if only I could get Codex to read rules.
by slashdave - I haven't been impressed with Opus 5 over the past ~30 hours either.
It's made countless careless mistakes folding in plan amendments after they get reviewed by Sol, and has produced sloppy mockups (e.g. buttons overflowing past cards) despite all the supposed verification claims.
by ValentineC - I think the type of persistence rewarded by benchmarks may be misaligned with instruction followingby wren6991
- I have a document generation task that I used to run with 4.8. This morning after it switched to 5, the documents were consistently 30%-40% longer for the same prompt... Not evaluated whether they are actually better or worse yet, but what was interesting was how consistently more verbose it was.by vidarh
- I’m not excited about using Opus 5, mainly because the way that I work atm — essentially peer programming — means I sandbox the agents and work with them closely. Opus 4.x encounters the sandbox and moves on with its day; Fable becomes increasingly fixated on it and does less and less of the actual task, focussing more and more on the limit it reached. I worry that, from your description, Opus 5 will do the same.by frio
- They are imo over-relying on Claude automemory here, which is terrible at contextualizing memory access and makes huge leaps that don’t make sense - except when it’s actually useful, which makes the problem even worse for an operator who can’t see the thinking process anymore.
Yes, I worked on a related project, no I don’t want you to use those memories to make assumptions which emerge as decisions that I didn’t want. With reasoning traces hidden, I am sometimes not even sure if it used those memories or just independently decided that PCI-DSS subsection-whatever is somehow relevant to this PR that has the word “credit”.
There is no way for me to fully configure memory preferences at a granularity which would be useful, and so I continue to use context files (and other tools, sometimes) to ensure the right memories are stored and surfaced at the right times.
There’s a lot of room for agent memory improvement across the ecosystem, and I don’t think the LLM providers should try to own this vertical slice. This will never happen though, because it makes us “sticky”.
Or maybe I’m holding it wrong.
by threecheese - I believe this is a move to make user spent even much more tokensby madduci
- I’ve rolled a small program to enforce consistency, lint rules, and human-authored files for Claude Memory.
It’s insanely powerful when doing by a human 100%. It’s conversely harmful when an agent manages it. There’s several papers about how LLM-managed memory is unequivocally terrible.
by fractorial - I don't like the memories, but I value them. I do a regular sweep of the memories, extract to harness or docs, then delete them.by chickensong
- Those auto memories are also annoying because by default they are not version controlled and land in a secret location. I much prefer storing stuff in a version controlled `CLAUDE.md` file.by jwr
- A CLAUDE.md file has no moat, it can be read by other agents.
Automemory can be weaved into the product in ways that make it harder to switch.
This is a company that's looking to IPO soon at a trillion+ dollar valuation, and they need to pull every lever to keep the users they got during the past year's boom.
by pavlov - This kind of stuff just makes me think nobody has any clue how these things work.
Why do I need a system prompt at all?
Why do I need another black box AIs to review the code of the black box AI why can’t these things get code right the first time.
Why is the best “coding model” in the world still making up APIs that don’t exist and do seemingly random unreleased changes that it wasn’t prompted for.
Why do these models (supposedly) keep getting “better” (on benchmarks) but continue to degrade in output quality while grtting more expensive for actual work?
I use Claude every day but I’m getting disillusioned by the so-called “progress”. If my employer wasn’t paying for my access I would not pay for any of these things. Don’t even get me started on the absolute brainrot inflicted on people that I work with from depending on these things every day, it’s depressing.
- This is like saying “why do I need a compiler when I can do better register allocation by hand in assembly?” Quick and “good enough” will win over “better.”by rayiner