I seem to recall Anthropic going on record saying that they don't do anything to model performance to stretch their compute capacity. I've anecdotally noticed massive peaks and troughs in performance week to week (albeit with Opus, not Fable).
I wonder what their official explanation for this behavior is.
I don’t think that’s what’s going on. I notice flaws on day one of model releases. But I also notice improvements if the model is truly more advanced than what I’m used to. Then over time the same questions or tasks return worse results.
What is actually stopping these model companies from running a model at full capacity on release then once its name rings out, start serving users quantized garbage?
What is actually stopping these model companies from running a model at full capacity on release then once its name rings out, start serving users quantized garbage?
...I mean, if they were actually doing this despite saying that they don't—promising one product and delivering something else—I think that would be fraud, no?
And, maybe it's one thing to secretly defraud normies like us (although class action lawsuits do exist), but I don't think major enterprises or the US military would take too kindly to it.
Are you telling me that companies might defraud people for millions and billions of dollars and pay fines that are 1000% less than their profits?" My goodness, you must live on a hell planet.
Sorry there for the smarminess but fraud is just a standard business practice these days and fines are the cost of doing business.
And I really am all for someone suing these companies forcing discovery so we can see how the sausage is made and how many eyeballs are in it.
They are deploying optimizations weekly (if not daily) with various AB tests. They don't manipulate model performance, but they do actively perform tests.
And here's another great example of how a bunch of people who don't know what's going on throw noise into the system. That post is simply confused: the 1m opus calls are the auto-mode classifier, actual agent calls are still in Fable.
Do you know why nobody outside the companies knows what's going on? Because they sell a black box with magic inside while steadfastly refusing to tell you if they are pushing buttons on said box while it is running.
Can you imagine how much fraud would exist in the gambling industry if the gambling commission didn't exist at all? Everytime an industry is unregulated and has high costs of entry the entities in the industry abuse their customers. The incentives are much too high for them not to.
Good point. I suppose watching the number go up is useful information in itself.
I have been using CC with DeepSeek 4.1 Flash lately, and it's nice to see how the sausage is being made (even if it's partly illusory, as CoT always is.)
Obviously. The standard pattern is that model X is basically AGI and wins all benchmarks, followed the next day by Y and Z, which both win all benchmarks, too.
Then weeks later people find out that they have been duped and complain that the models have been quantized or employ worse inference.
Buy decent coffee instead of your $200 subscription and sidestep all the scams.
Well I happen to enjoy coffee and $200 AI plans. What if Blue Bottle started watering down it's coffee? Is your answer to stop drinking coffee and make myself tea instead?
Evidence that vendors are being misleading in what they are delivering is important to share, whether or not you personally approve of that product.
Well sorry, still have to get decent AI somewhere. Productivity without AI is about 5x less. I am not comfortable with paying Chinese companies, and no Western companies provide subscription-based pricing for open models.
Anecdotally, I have found the same. I spend a lot of time with these frontier models, brainstorming, etc. and the drop in performance from, say, week 1 to week 8 is often massive. Whereas in the beginning, it seemed like a capable research assistant, by the end of week 8 or so it starts acting like a puppy dog eager to make its 'master' happy for a few treats.
Reminds me of how slot machine users swear the odds have changed on a machine.
also when someone says you just have to prompt it a certain way it reminds me of people who think they can get better results out of a slot machine by pressing buttons in a certain order
The providers of these models also design the UX similarly to slot machines (run it x amount of times for better results, multiplying your spend) this isnt a coincidence and they're playing into the gambler mentality, and probably hire UX designers that specialize in this.
Wtf are you on my dude. Anthropic UI is designed like a slot machine? Hiring slot machine specialists? Sometimes I can’t believe im even on HN anymore with comments like this.
I think some of it comes from that they do not publicly let you see the random seed. So each time you ask the answer is different (like a slot machine) and if they let users use the random seed it would let people much more accurately assess if an underlying model changed somehow (same seed and same input will always have the same output).
Of course the closed Anthropic would never share this, it would definitely take away the 'magic' feeling of the AI
With models there are a bunch of other dials that can be tuned even if the model itself remains exactly the same.
Are those dials set the same across all hardware configurations and clusters? Does model behavior average out the same across different hardware?
There are just too many different buttons that can be set to really trust a provider either not to directly commit fraud, or indirectly commit fraud with system complexity affecting the output.
Well, running an LLM X amount of times does give you better results provided you are willing to select the best one out of the X yourself.
But I agree with your general point. One of the reasons subscription plans are cheaper because they modulate usage in this way based on demand. They can also recover compute more coarsely via usage resets (which give positive PR).
Well yeah. If for some task you find it easier to just do it yourself then you should. But you can improve the situation even if you can't entirely automate it by automating parts of the verification thereby making it easier to human-do larger verifications when X>1. But in many cases even that is not possible.
The progress however is such that the number of tasks that you can do with >p% automated and X=1 keeps increasing. So many times just waiting works. Of course, here also it changes from field to field. There are some tasks at which AI hasn't even gotten started, others where it has already peaked, others where it's increasing slowly, and others where it's increasing fast.
The actual tokens might be non-deterministic, but you could look for proxy measures that are supposed to be invariant. Eg. correctness/performance on benchmarks, "thinking level" on complex problems, etc
I strongly believe that the real Fable is the one we had for a few days in June. Then they nerfed the model a bit after the government pulled it off the market. What we have now is something less, but still good
I also believe this. Fable post-ban was never the same. At the least, whatever system prompt munging or pre/post filtering they did to strengthen the guardrails nerfed it.
It is clear by now to me that Anthropic is constantly trying to find a kind of “auto” degradation perhaps to save money on work it thinks does not require high reasoning. I always use max reasoning and I can clearly see differences between the models when they release and after 3-4 weeks. I think they give a kind of intelligence boost also for new accounts.
Just yesterday I was thinking about gpt-5.6-luna. I made it my default model in Hermes during its fist week of launch. It was just as good as 5.5 which was my previous default. But over the last 2 or 3 weeks I've seen how dumb it is now. I have to be very explicit with it.
For example, I used to be able to prompt "Check the system logs on <server> for...." and it would just figure it out. Yesterday I asked "Did <service> on <server> complete the overnight job" and all it said was "that service is not installed on my host"
I had to tell it to ssh into the server and run journlctl to check it
Anecdotal, I know, but they all seem to be less capable with time.
Same exact experience. I worked with both Fable and Sol foe the last two months, daily for several hours, and got used to the very bright, quick thinking, proactive even.
As of last 2 weeks or so both models are nearly on par with DeepSeek4.1 now, which I also use a lot. They're still better, but that difference is not as pronounced as before and, importantly, the frustration level is now on par.
Whatever they're doing will surely drive people to less advanced but predictable, self hosted open models. I sure would rather use DS4.1 with Qwen/GLM in adversarial mode than deal with this b/s I pay significant amount of money.
Me and my friends have been contemplating on getting an Ultra M5 256 and splitting the cost. PI harness is so good now that this is really a viable alternative.
I'm fairly sure it's just luck of the draw if you get put onto a quant'd model or not. I've seen luna xhigh change intelligence fairly drastically on a day to day basis.
Really this is the base problem. You have zero idea where and how your prompt is being executed.
If for example AWS sells you a 2xLarge server there may be some variability in performance but it's going to be averaged out very well.
When it comes to AI services executing your model there is absolutely no information on what and with what settings your model is being executed. Hell, you have no idea if it even is the model you're paying for. Add that models are not deterministic so variability can be pretty large.
This leads to a common set of dynamics that induce cheating behavior in humans. For example, is there a mix of different hardware. Does lessor hardware use different settings? How do you know xhigh is what your prompt ran under. Anthropic has a proven history of running your prompt silently under different models.
This is a huge mess that needs and will be regulated or sued heavily over. Hell, with as many people out there that hate AI it might be easier than one thinks to have a state sue the providers on this and elicit a huge amount of discovery.
& the nice thing about Hermes (since its open source) is you can be reasonably sure that behavior change is coming from the model and not the harness. (probably)
The smart takeaway is not skepticism or snark, but understanding that once the new datacenter buildout starts coming online, cheap and widespread access to even the current frontier models (without strict thinking limits) will blow the economy wide open.
(ie, even a pause in AI training isn't going to stop the train where AI flips the economy upside down, we've barely even seen the impact of the current frontier)
The question I have is this only happening for a subset of users working in specific areas, such as AI or distributed systems (https://news.ycombinator.com/item?id=48742153), or is this across the board? I am working on distributed systems. Today Fable is mostly unusable. It resembles Opus, so I went looking to see if anyone else is having issues. Sure enough.
I work in embedded systems. I have seen the same thing happening day by day from Opus. Some days it’s okay to use and performs well. Other days I have to correct it repeatedly and remind it of information already in the prompt earlier (before compaction!) and still other times it’s infuriatingly stupid.
It’s a slot machine for what they’re actually giving us behind the opaque paywalls.
I have no hard data but I have a strong feeling this morning that something's wrong with Fable 5 compared to Friday evening.
Just an hour ago I had Fable correctly identify an unused method that could be deleted. I then immediately get a diff for an exact duplicate method, and then Fable outputting, "I accidentally duplicated <method> instead of deleting it. Removing both copies now."
The remaining morning complaints that makes it feel like something's off is that it will do a lot of "thinking" for simple things that previously took very little time. And it got very lost and completely mixed up DE-91M predicate names and implementations. Just absolute disaster code that I had over the past months come to generally expect it to do without issue.
Glad I carefully review everything. I think what I need is reliability and consistency. But it feels like picking a model from the list doesn't guarantee that: that the models' "brain" is open on the table and they're screwing with it.
Can you elaborate on the mechanism of this degradation? If resources are not available I would expect a request to fail with a message about resources not available. Do they tweak back end model capabilities to maintain service in a degraded state?
Dollars to donuts, they are speculating, and not privy to inside information on the topic.
However, I believe that runtime model quantization is possible with some publicly-available inference engines (e.g. vLLM), so its not beyond belief that the closed labs do quantize at runtime, either to allocate compute, or to nudge users towards a preferred model (e.g. make the incumbent model dumber to push people to use the latest-and-greatest model, or vice versa to ease the load on the latest model, which is typically larger than the old one).
An AI lab will never volunteer the information because it opens them up to lawsuits if they are purposely degrading service and not letting users know.
They can limit how hard the model thinks for a given effort. Suddenly xhigh only thinks as hard as high did, and high shifts down to medium effort, and so on.
They can also serve quantized models. And this has the benefit of practically not showing up in benchmarks at all even if the user experience is obviously degraded.
The other major thing the labs do is silently drop the usage limits. This has become very noticeable for codex users who are suddenly burning through their weekly usage in a few hours.
Yea, if you ever run your own models on a GPU there are a whole ton of different dials you can adjust that drastically affect compute use, memory use, and output token quality, and number of tokens held in memory.
If anyone reading has a GPU it's worthwhile just messing with a smaller model for a bit to watch how the settings affect output.
I have no reason to doubt the claims of the employees at OpenAI and Anthropic who have told us personally multiple times, including here on HN, that they do not degrade the models in order to reduce load.
As for the endlessly long analysis in the OP, it appears it's based on analyzing their random usage data rather than any fixed benchmark. I don't think it makes much sense.
I would rather wait in a queue than be routed to a degraded model. And if they _have_ to degrade the models, then I wish they would fucking tell us. Instead, it's "I have a strong feeling".
That we have to guess at this is by far the worst part of the AI era. It feels like a dark cloud over my productivity. It makes my body tense for the entire day when it happens. Not healthy.
They have repeatedly said they do not ever intentionally reduce model quality and do not degrade in this way, and that a model version number is always the same.
But, of course, OP is an empirical claim to the contrary, and I'd be curious to see if anyone (who's been capturing data over these timeframes) can replicate the same results and if Anthropic has any comment.
Every official statement I've seen around this is careful to say that they "don't intentionally reduce model quality", which leaves plenty of room for "we adjusted some knobs and our evals show performance is materially the same".
However, I also agree that I haven't seen any robust data from someone tracking it daily/weekly. The handful of sites purporting to do this aren't even running it enough times to hit stat sig.
edit: someone linked one elsewhere in this thread called AI Stupid Level - they "run 7 trials instead of just 1". I don't blame them. Doing this in a statistically sound manner would cost a small fortune.
I kind of feel "reduce the amount of thinking tokens produced" would fall under degrading model quality.
In any case, I am willing to believe it's possible something degraded, but so far I have not seen any empirical evidence of it since the previous incident with the inference and harness bugs. I lean towards Anthropic probably not intentionally doing anything like this without disclosing it beforehand.
The issue here is you have to think like a lawyer trying to weasel out of making an empirical statement.
For example "We didn't change any settings, but when GPU use gets high the run time of a prompt is lessened. But you must remember this is always in effect so nothing changed at all. This happens occasionally on random prompts some of the time, and when it's busy it happens all of the time".
In someones eye this would fit the letter of the law but not the spirit of the law that you hold.
The Claude models definitely felt more susceptible to moods, like you could leave them for a few hours, come back and it suddenly was unable to do things which it was doing just earlier, which tellingly is never an experience I've had with an open model.
Honestly I lost patience with Anthropic both clearly messing around with things like this and their agitation over regulation. They aren't good actors, and quite why so many blindly trust them with their company crown jewels is a mystery.
It's supposed to be for token optimization (https://code.claude.com/docs/en/prompt-caching), but are people experiencing degraded performance when you let Claude Code sit for hours/days and come back?
If you follow reddit forums for claude code, its common to see people, on the same day, claiming that Opus/Fable is especially smart today, and especially dumb today.
I think people are still not used to non deterministic tools like this, and human perception is absolutely horrible at evaluating trends like this no matter how smart, clever, and experienced you are.
If you have a bank of rigorously tested benchmarks that you run every few days, with enough trials to know what your standard deviation is, and you are getting significant trends over time with those, that would be interesting.
But "I have a feeling" and "Seems like" really isn't a reliable signal at all, humans just can't handle perceiving these things reliably. On top of that changes in your work environment can easily pollute LLMs and change quality of results. Are things getting added to your memory or claude.md files that you don't realize? Is your project growing in size and thus claude is performing worse as more context is needed to work with it? etc etc
and human perception is absolutely horrible at evaluating trends like this
The need to have a mental measure of competence for your fellow man is, most likely, a pre-human skill, probably with a dedicated bit of neurons for it. I think the problem is that those instincts were co-evolved with our fellow man, and, as you say, don't apply at all to a more non-deterministic system that, fundamentally, lacks some logic faculties that even small children have (simple riddle modifications, car wash question, etc).
I think people are still not used to non deterministic tools like this, and human perception is absolutely horrible at evaluating trends like this no matter how smart, clever, and experienced you are.
The implication is that humans are unreliable and shouldn't be trusted.
Or humans have certain shorthands when they complain on reddit, but their diagnoses are accurate for the specific context? If my AI does something stupid, am I not allowed to call it out? A NS-solving AI is still capable of not satisfying the abstract thing called the user experience. People have intelligent thoughts without compiling to lean.
OK, you say. Then let's get an aggregate benchmark for "intelligence". That doesn't prove that AI didn't flounder a specific use case that the user requested.
Classic moves: Humans are unreliable, converge to some "objective" benchmark that necessarily will quotient out the special cases, etc. Wonder how we'll be solving these issues in the AGI era - well, if you have an AGI that just replicates itself, dominates everybody because it's a machine and humans are soft fleshy creatures, and agrees with itself, fine. But part of the beauty of human experience is the messy part, and providing value is in the messy part.
In other industries of chance we have regulators that ensure compliance and that the providers aren't cheating.
At the end of the day the highest quality of benchmark tells you nothing if the man behind the curtain is constantly changing variables on you. You have no idea if you're really testing the same thing at all. So when you run your test at the top level on their system you're seeing lets say a 30% difference in quality most of the time, you have no idea if you should really only see a 5% difference in quality if you were running a local model with stable settings.
It’s load shedding. They’re reducing consumption for capacity balancing at your expense. Whenever there are rate limiting storms Claude gets dumber. They also shift capacity for new releases, and Claude gets dumber leading up to it.
Self run infrastructure won’t have this cost but you have to manage the capacity and rollouts yourself, at which point it’s more obvious what’s happening, but the effects will be the same. The not knowing makes it harder, but also harder to plan your own work around.
Gemini Chat is constantly throwing, "Pro is in high demand right now, a different model was used for this generation," too.
I'm thinking they're all running out of physical resources. It's the DotCom bubble all over again; rollout of the physical infrastructure that's necessary to keep all of the pie-in-the-sky promises will not happen on the timescales that investors can work with, and they will panic when they realize this.
EDIT: And, frankly, I can't wait. I'm tired of the sketchy and dishonest way these companies are behaving.
This is like shared clouds back in the day where if someone is using the CPU more it impacts you, just pool every one to the same service. There should be an SLA but for the intelligence of these models, otherwise, you are sold fable but with the intelligence of a table.
This is a project i wanted to implement for a long time. It regularly benchmarks cloud hosted models with private benchmarks.
Not just openai & anthropic, popular openrouter models too.
Tests their intelligence, not their diligence.
Sadly i cant think of a way to monetize the service. Also if it ever gets famous enough labs would try to game the system, it would be cat&mouse game that i am not willing to waste time on without any monetary gain.
I built GitHub.com/adrianco/retort to do this. It’s runs lots of experiments and you can contribute results if you have some spare tokens. You can add your own tests, and it runs Claude, Codex, Gemini, Hermes for local models.
So in 5 years will they lose a suit for intentionally deceiving users? Or is something baked into the ToS by now that allows them to adjust things like this?
I do not know a single senior developer who likes Claude anymore. I do not use their API (Sonnet, Haiku, Opus) anymore and am sending my money to offshore companies such as z.ai (GLM) and QWEN.
The American companies have become extremely deceptive and scammy. I hate Anthropic and OpenAI and can't wait to have a decent GPU at home to use at least Opus or a fable-like open-weight model. This is the current dream of every developer. But NVIDIA is not going to let that happen anytime soon, so maybe China can come up with a GPU that destroys NVIDIA. I pray.
I've followed a few trackers, eg https://marginlab.ai/trackers/claude-code/ , for awhile. For Claude Code the trend, it seems to me at least, is fewer tokens to do the same or better job. Prompt changes, tool ergonomics changes, etc.; I'd be shocked if they didn't A/B every release. Less thinking as measured by tokens isn't necessarily bad if you can get the same results by making it think about the "right" things or structure. They obviously screw up sometimes, and I've always been suspicious with hidden tokens, but I haven't found evidence quality intentionally degrades over time.
Same. With some 500 hours of usage in just my project at home, across both the $200 Claude and Codex subscriptions, I have not once encountered a situation where I would have attributed unsatisfactory results to a degradation in the model.
I've seen bugs in the harnesses, sure, but never anything in the actual model where I could have said with any certainty that it's not just regular variation or me having a bad day myself.
No idea where people get the confidence from to make such claims every other week.
These analyses are much better than these Twitter charts.
I don't think anyone is reading the details for the Twitter post because it was not an actual benchmark. They did a post-hoc analysis of their logs from day to day.
Their random collection of prompts for each day is not a benchmark.
The site you linked is a much better example of a real benchmark being repeated over time.
The Office of Weights and Measures exists because, long before any of us were born, in 1836, companies were up to shady shit and consumers were paying for inconsistent products. I.E. Being scammed.
AI companies should be subject to the OWM like any other company that sells a product that varies in weight. Perhaps when a sane administration is re-elected; one that can read history books and comprehend why our regulations exist in the first place. Or have even a semblance of respect for its citizenry.
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You're not buying a gallon of milk or a pound of flour. You're buying hosted software that the host reserves the right to modify.
Fluctuations of a few percentage points are to be expected and should not surprise anyone who knows how LLMs work.
This Twitter analysis of Fable 5 is not that at all. They analyzed their coding sessions and blamed all of the fluctuations on Fable changing. They then compared to ARC-AGI-2 questions as the benchmark for thinking tokens and tried to stir up anger that coding turns don't produce as many thinking tokens as the ARC-AGI-2 problems.
This page has been in 'New model — collecting baseline data. Degradation detection paused.' state for months now. It seems to never say 'degraded'.
If you look at the graphs, the latest benchmarks are showing a pretty significant dip, and they match pretty well with some horrible experiences I've had in recent weeks. You can see token usage steadily going down, matching exactly what the author measured on his own.
This page has been in 'New model — collecting baseline data. Degradation detection paused.' state for months now. It seems to never say 'degraded'.
Click the part at the end that says "View historical performance". They wait to collect more data about a new model before adding it to the overall charts.
The overall solution rate continues to climb when new models are considered.
If you look at the graphs, the latest benchmarks are showing a pretty significant dip, and they match pretty well with some horrible experiences I've had in recent weeks. You can see token usage steadily going down, matching exactly what the author measured on his own.
The y-axis is amplified to make differences look larger than they are.
Hover over the dots to see the confidence interval. A 1-2% change means nothing.
I stopped using Fable long time ago. It's worse than Sonnet. Opus is not much better.
This cycle of new model running at full quantisation and then nerfed few days / weeks after premiere should be called out. Anthropic should also drop the adaptive reasoning scam.
If I pay for Fable, I should get full, not nerfed model at honest pricing.
Regulators should investigate them.
OpenAI is no different. Astra has basically the same problem.
The ROI just isn't there. It feels like Fable is in the same place Opus was early last year; at best marginal improvement that's barely noticeable over the lower model, for 10x the cost. I'm sure it'll take over as the workhorse as Opus did once they get it down, but right now it just doesn't make sense
Makes sense, no? Test time compute is something you can vary, so it makes sense that you start covertly reducing it once the model has already made it's splash.
Could there be a benefit to releasing a new model, slowly dumbing it down over a couple months, then releasing a new model that’s marginally if at all better than the original to create a perceived improvement when in reality there isn’t really one?
For an industry that’s stagnant in progress yet relies on new frequent releases to survive (non-progress being an existential risk), this could make sense.
I have no idea if that’s what’s happened, I completely pulled it out of my butt. And I have no idea is the actual frontier is stagnating.
Could there be a benefit to releasing a new model, slowly dumbing it down over a couple months, then releasing a new model that’s marginally if at all better than the original to create a perceived improvement when in reality there isn’t really one?
Exactly what I am saying for months now. And it's exactly the reason why I am shifting to open weight models now. Just bought myself a 2x DGX Spark Cluster. Will run Qwen3.8 Flash Next on it, maybe Qwen4 when it comes out.
Not only do I have full control over quantization and inference, but also will I experience a constant level of quality. It won't be frontier. But it will be stable, and that's enough reason for me to switch. Also I will likely save some money on subscriptions.
I wouldn't be so sure. The generosity of the subscription plans has declined GREATLY over the past 6 months or so. They are likely trending towards api pricing parity. In which case, having your own hardware makes sense if you can utilize it well.
Last time I estimated, it would only take 3 months to pay back because the 1TB Mac Mini running Qwen RSIingly developed ASI and made infinity dollars off of crypto and I got put in jail by the SEC.
flash next is good, I've been running it for like 2 weeks now and it's pretty solid, hope you like it and it meets your needs. I still lean on Claude and codex a fair bit for harder stuff, but I'm rapidly moving towards 2x $20 plans instead of 2x $200 plans
I don’t know what people do with the open models but having tried a lot of them I just can’t make it make sense. they’re too dumb and it effectively makes them useless (to me). it’s probably worth being honest about the low ceiling here.
Every SOTA model I've used at launch uses deeper, longer inference then gradually turns down over time, until the next model comes out which seems to be trained on some new data, but mostly performance due to deeper longer inference for another period.
I have not been attributing it so much to malice, just that all the major cloud vendors seem to be running at full capacity, and can't build new datacenters fast enough. I just kind of assumed that as they got busy training newer models, that they allocated less resources to handle the existing systems, because they aren't able to get more capacity right now.
I’m not sure why this point keeps coming up — if your service/product is so popular that it’s capacity-constrained, then the answer is to raise prices, not degrade service, because the demand should be inelastic.
Raising prices also has second order effects, like consumer and business expectations around how widespread the tech can be. Valuations depend on it being reasonably affordable to roll out on a much more massive scale than today. If people get the impression that it seems too limited to very rich people (200 is affordable for a North American / Western European professional), the impression about the trajectory will change.
The Opus 4-6,4-8,5 arc is exactly this. As one person commented in here, opus 5 is a terrorist. This is undeniable. Opus 4-6 was awesome. 4-8 was worse behaviorally but produced better code.
Fable seems to be following the same enshittification arc of other Anthropic models.
Generally OpenAI seems to be taking the opposite approach with an increasing improvement over time. As sad as I feel to say this, open ai seems to have the right strategy. Making your product worse over time rarely plays well with customers. At this point it feel often hard to justify using Anthropic for anything. I generally like Anthropic better as a company and they really had the initiative and advantage and customer good will, then proceeded to squander it faster than a cigarette company or the Sacklers could have.
This sounds similar to rumors about how SSD companies work. First they would design a new drive with better performance that everyone uses to benchmark against other models; then slowly change its parts to worse ones, either because they are cheaper, the originals are no longer available, or whatever reason
There must be some benefit if all the providers are doing it independently.
GPT5.6-Sol on Max thinking just became regarded as of a few days ago.
The boosters will tell me it’s my fault for using such an old, cheap out-of-date low quality near useless wish.com model (that was SOTA and better than human coders one month ago).
Again, I’m out of my element here, but isn’t the entire industry dependent on “new better releases frequently”? If so, and if no one has made any meaningful breakthrough, might they all pursue this kind of deception just to stay afloat/“competitive”/relevant?
Could there be a benefit to releasing a new model, slowly dumbing it down over a couple months, then releasing a new model that’s marginally if at all better than the original to create a perceived improvement when in reality there isn’t really one?
Not unless your competitors do the same, or else you will only be perceived as falling behind others.
Yep, that's what they've been doing for a long while now. Also the amount of tokens you get per sub varies drastically from month to month. Needs to be regulated.
to create a perceived improvement when in reality there isn’t really one?
This wouldn't explain progress on benchmarks (including closed sets), or the fact that newer models are providing solutions to major math problems that older models cannot.
* Release new model that scores an arbitrary 100 on a benchmark
* Get everyone to talk about you as the first model to ever score 100 on the 100benchmark.
* Tune it down over time so that you end up only scoring 75 on the benchmark and people get used to it, gaslight them into thinking it never changed or that it's just a harness problem, they can't run the old version locally anyways to verify. This also cuts your costs in half. Your gross margin on API calls goes from 70% to 150%.
* Release new model that scores 120 on the benchmark and advertise it as 50% better than the current model, while it's only in practice a minor increment. Everyone praises it as the second coming of Jesus Christ.
* Get everyone to talk about you as the first model to ever score 120 on the 100benchmark.
This is a good point I hadn’t considered, thank you.
Is there any training variable here? For example, can a model released in October perform better on the same benchmarks vs its predecessor released in July just by virtue of training on newer data that was made available on those 3 months?
Sorry if it’s a dumb question, I don’t really know much about the topic.
Instead of finding a nerfed model, after six weeks of reconstructing wire logs, parsing transcripts, analyzing output tokenization, and staring at data, I found a much deeper issue. The model identity had remained the same, but the inference regime being delivered behind that model had not.
Is this something specific that shows up in the wire log, or is this the author's intepretation? The fact that Claude Code versions change over time in the test is suspicious. Anthropic has stated in the past that the underlying model behavior does not change over time, but Claude Code will change from version to version and this is expected. So if it's just Claude Code more aggressively tuning some knob in its requests, that's a pretty different thing than the underlying model changing.
If you thought this was a repeated test of the same problems showing fluctuating performance, it's not. They set up a MITM proxy between Claude and the servers and ran analysis on the work they were doing.
So those ups and downs in the charts, which they plotted with sub-daily resolution, are just as much a function of their work changing from day to day. It's like plotting the miles per gallon of your car and blaming the gas station when the number goes up and down, without admitting that some days you drive to the grocery store on surface roads and other days you drive up a mountain on the freeway.
The corpus analyzed in Charts 1-5 comes exclusively from Fable 5, at xhigh and max effort levels, during sustained production work across a diverse set of projects and workloads. Data was aggregated from transcripts and live wire logs
The analysis (which feels very vibe-slop) gets worse from there. In the second half they take thinking token counts for ARC-AGI-2, thinking problems designed to stress LLMs, and compare their average thinking-tokens-per-turn counts to that!
If you don't realize why this is so flawed: ARC-AGI-2 is a benchmark meant to collect problems thought to be extremely difficult, nearly impossible, for LLMs. If your goal was to cherry-pick a mislead example which would produce the highest number of thinking tokens, this is it!
Your daily coding work should not be producing a proportional number of thinking tokens on every invocation while it reads through some source code or edits a couple lines in a file.
You don't want to maximize the number of thinking tokens. You want problems solved accurately with the minimum number of tokens.
Confirmation bias runs deep on this topic so I assume few people read the analysis before posting, but as far as experiments go it's basically useless. Are they changing something on the server? I don't know, but this analysis isn't useful for answering that question.
Yes, this is my production corpus, across 65 usage days, two subscription accounts, three machines, 25 project groups, and 213 sessions, across 43,261 invocations and 7,583 turns. Use your own data if you want to prove or refute what was seen in my corpus.
The "ups and downs in the chart" were not plotted with sub-daily resolution. Specifically, the two-month temporal chart uses a 3.5-day Gaussian bandwidth which is meant to reduce short-term noise while retaining broader changes.
Additionally, a separate episodic analysis identified multi-day changes in delivered thinking. And those episodes were predictive of held-out work. The more projects pulled into an ensemble, the more predictive they were of delivered thinking tokens for held-out projects during the episode.
The point of the benchmarks is to establish a baseline for what thinking-token counts one should expect from specific effort levels using published numbers, not what every response should be delivered. If you looked closer, you would see that P90 invocations were still delivered 13x thinking tokens below that level.
So you don't have to provide a generous interpretation of my workload if you don't want to. Remove all of the zero-thinking token responses, redistribute those samples across the distribution, and then tell me if it magically shifts right and starts delivering anything close to published numbers. Only -46- out of 36,374 July and August invocations even broke 16k thinking tokens - only 0.13% of the total. You are welcome to present what percentile you think is a fair comparison to make here.
If you would like to denigrate a month of my time as vibe-slop, that is your prerogative. You can even be dismissive of my workload, if you want, even if my background should tell you otherwise. But if you want to knock a month of someone's time, do it with your own data to at least help move the conversation forward.
Use your own data if you want to prove or refute what was seen in my corpus.
I don't think you understand. What you posted is highly dependent on your corpus. I can't "refute" anything because it's not available and it's the major variable in the experiment.
The point of the benchmarks to establish a baseline for what thinking-token counts one should expect from specific effort levels using published, not what every response should be delivered. If you looked closer, you would see that P90 invocations were still delivered 13x thinking tokens below that level.
I think you're missing something from that first sentence, but I assume you're talking about the comparison to ARC-AGI-2 published thinking tokens?
It should be blindingly obvious that you do not want your thinking token counts to be as high as a benchmark that was designed to push LLMs to their limit.
Only -46- out of 36,374 July and August invocations even broke 16k thinking tokens - only 0.13% of the total. You are welcome to present what percentile you think is a fair comparison to make here.
What point are you even trying to make?
Again, you don't want invocations to be burning 16K thinking tokens except for rare problems that 1) must be solved in one step and 2) are designed to be entirely self-contained thinking in that step.
You're trying to compare development work to a benchmark that encapsulates complex thinking into a single step.
Coding work is iterative and works in incremental steps: It runs commands, reads more files, checks the web. Thinking tokens should be low for your turns.
ARC-AGI problems have an input and an output. They look like this: https://arcprize.org/tasks/b5ca7ac4 They have more thinking tokens because that's the entire state. They get one output and it's constrained.
But if you want to knock a month of someone's time, do it with your own data to at least help move the conversation forward.
It is fair to discuss a published analysis. Saying that only people who bring their own month of equivalent analysis (which conveniently would take another month to produce) are allowed to critique it is just a cheap trick to shut people down.
If you post big claims, they are open to analysis and review by others
After reading what you had to add to this discussion, I have only two things to leave you with:
1/ if the point of setting xhigh or max effort on a "reasoning model" is -not- to have additional reasoning tokens applied to the problem, then I fear we are all using AI wrong
2/ the decorum with which you "review" someone's work in public is entirely your choice. the only "cheap trick" on the internet is being a pseudonymous ass.
1/ if the point of setting xhigh or max effort on a "reasoning model" is -not- to have additional reasoning tokens applied to the problem, then I fear we are all using AI wrong
You keep moving the goalposts. The core flaws in your analysis are that you assumed the variation was 100% server side and didn't admit that the inputs were random and different every day, and that you tried to compare to ARC-AGI-2 as a benchmark.
Comparing ARC-AGI-2 thinking tokens to agentic coding thinking tokens is as misleading as it gets, because these are completely different use cases.
Please stop and think about this for one second. Do you really want Anthropic to spend 30K thinking tokens on every input, just because that's what ARC-AGI-2 problems required? What would your inference bill look like if this was the case?
The premise of your ARC-AGI-2 comparison is broken.
2/ the decorum with which you "review" someone's work in public is entirely your choice. the only "cheap trick" on the internet is being a pseudonymous ass.
Ironic to accuse someone of cheap tricks as you pull out an ad hominem insult after someone explains the flaws in your reasoning.
My points stand: You can't claim this is a chart of Anthropic changing the server when you were feeding it random input every day and plotting the output as if the line should be flat. You can't compare agentic coding to single-turn ARC-AGI-2 problems.
This is exactly what I have been experiencing and the difference is night and day! We have been advertised and given a taste of what Fable was and after that been served an exteme watered down version. It is so bad that sometimes chatgpt feels better.
Opus 4.8 was smarter and possibly 10x faster than Opus 5, too. They are dumbing things down on purpose. I am praying for open models to become at least as smart as Fable soon so we can ditch these shitty, lying companies.
I was rooting for Anthropic 2 years ago, but now I have become an extremely bitter customer. Just another version of OpenAI, if not shittier.
I seem to recall Anthropic going on record saying that they don't do anything to model performance to stretch their compute capacity. I've anecdotally noticed massive peaks and troughs in performance week to week (albeit with Opus, not Fable).
I wonder what their official explanation for this behavior is.
Last time they were called out, it was a regression in Claude code itself.
At least that's their explanation. Either way, it wasn't a good look for "vibecoding" but it got brushed over.
When something is new, its capabilities feel incredible. Over time, those same capabilities become mundane, and you start to notice the flaws.
(Now, if TFA is actually measuring reasoning tokens, that's quite different! It's not entirely obvious to me how he is measuring.)
I don’t think that’s what’s going on. I notice flaws on day one of model releases. But I also notice improvements if the model is truly more advanced than what I’m used to. Then over time the same questions or tasks return worse results.
What is actually stopping these model companies from running a model at full capacity on release then once its name rings out, start serving users quantized garbage?
...I mean, if they were actually doing this despite saying that they don't—promising one product and delivering something else—I think that would be fraud, no?
And, maybe it's one thing to secretly defraud normies like us (although class action lawsuits do exist), but I don't think major enterprises or the US military would take too kindly to it.
Are you telling me that companies might defraud people for millions and billions of dollars and pay fines that are 1000% less than their profits?" My goodness, you must live on a hell planet.
Sorry there for the smarminess but fraud is just a standard business practice these days and fines are the cost of doing business.
And I really am all for someone suing these companies forcing discovery so we can see how the sausage is made and how many eyeballs are in it.
They are deploying optimizations weekly (if not daily) with various AB tests. They don't manipulate model performance, but they do actively perform tests.
They did. More than once...
Anthropic Walks Back Policy That Could Have ‘Sabotaged’ AI Researchers Using Claude https://www.wired.com/story/anthropic-responds-to-backlash-o...
But it's still happening: https://github.com/anthropics/claude-code/issues/81759
And here's another great example of how a bunch of people who don't know what's going on throw noise into the system. That post is simply confused: the 1m opus calls are the auto-mode classifier, actual agent calls are still in Fable.
Look at the usage. Fable wasn't being consumed.
Do you know why nobody outside the companies knows what's going on? Because they sell a black box with magic inside while steadfastly refusing to tell you if they are pushing buttons on said box while it is running.
Can you imagine how much fraud would exist in the gambling industry if the gambling commission didn't exist at all? Everytime an industry is unregulated and has high costs of entry the entities in the industry abuse their customers. The incentives are much too high for them not to.
You're right to push back, and one honest caveat -- they could just be lying.
How do you measure thinking tokens? They don't send those back to the client.
They tell you how many tokens are used, however, right? Otherwise you couldn't see your own token consumption.
Good point. I suppose watching the number go up is useful information in itself.
I have been using CC with DeepSeek 4.1 Flash lately, and it's nice to see how the sausage is being made (even if it's partly illusory, as CoT always is.)
Obviously. The standard pattern is that model X is basically AGI and wins all benchmarks, followed the next day by Y and Z, which both win all benchmarks, too.
Then weeks later people find out that they have been duped and complain that the models have been quantized or employ worse inference.
Buy decent coffee instead of your $200 subscription and sidestep all the scams.
You forgot a stage or two:
1: "Our model will bring about the end of all things. Flee, flee for your lives"
2: "Our model is basically AGI"
3: "Our model will be available in limited release next week"
4: "Everybody who subscribes at the $200 level gets access now"
5: "Everybody who subscribes at the $20 level gets access now"
6, at least at Google: "Our model will be shoved down your throat every time you do a search, whether you want it or not"
0. "our model is too dangerous to release to pubic"
Google's search AI actually its too dangerous to release to the public. I have relatives routinely citing it as their source for medical advice.
I have quite strongly told them, in no uncertain terms, that they are going to kill themselves doing that.
Be sure to eat plenty of rocks in your daily diet, they are chock full of valuable minerals!
Well I happen to enjoy coffee and $200 AI plans. What if Blue Bottle started watering down it's coffee? Is your answer to stop drinking coffee and make myself tea instead?
Evidence that vendors are being misleading in what they are delivering is important to share, whether or not you personally approve of that product.
Well sorry, still have to get decent AI somewhere. Productivity without AI is about 5x less. I am not comfortable with paying Chinese companies, and no Western companies provide subscription-based pricing for open models.
Anecdotally, I have found the same. I spend a lot of time with these frontier models, brainstorming, etc. and the drop in performance from, say, week 1 to week 8 is often massive. Whereas in the beginning, it seemed like a capable research assistant, by the end of week 8 or so it starts acting like a puppy dog eager to make its 'master' happy for a few treats.
Reminds me of how slot machine users swear the odds have changed on a machine.
also when someone says you just have to prompt it a certain way it reminds me of people who think they can get better results out of a slot machine by pressing buttons in a certain order
The providers of these models also design the UX similarly to slot machines (run it x amount of times for better results, multiplying your spend) this isnt a coincidence and they're playing into the gambler mentality, and probably hire UX designers that specialize in this.
Wtf are you on my dude. Anthropic UI is designed like a slot machine? Hiring slot machine specialists? Sometimes I can’t believe im even on HN anymore with comments like this.
I think some of it comes from that they do not publicly let you see the random seed. So each time you ask the answer is different (like a slot machine) and if they let users use the random seed it would let people much more accurately assess if an underlying model changed somehow (same seed and same input will always have the same output).
Of course the closed Anthropic would never share this, it would definitely take away the 'magic' feeling of the AI
To my understanding, with batched inference and other "optimizations" you wouldn't get the exact same token predictions even with temp=0.0.
With models there are a bunch of other dials that can be tuned even if the model itself remains exactly the same.
Are those dials set the same across all hardware configurations and clusters? Does model behavior average out the same across different hardware?
There are just too many different buttons that can be set to really trust a provider either not to directly commit fraud, or indirectly commit fraud with system complexity affecting the output.
Well, running an LLM X amount of times does give you better results provided you are willing to select the best one out of the X yourself.
But I agree with your general point. One of the reasons subscription plans are cheaper because they modulate usage in this way based on demand. They can also recover compute more coarsely via usage resets (which give positive PR).
At that point I might as well do it myself
Well yeah. If for some task you find it easier to just do it yourself then you should. But you can improve the situation even if you can't entirely automate it by automating parts of the verification thereby making it easier to human-do larger verifications when X>1. But in many cases even that is not possible.
The progress however is such that the number of tasks that you can do with >p% automated and X=1 keeps increasing. So many times just waiting works. Of course, here also it changes from field to field. There are some tasks at which AI hasn't even gotten started, others where it has already peaked, others where it's increasing slowly, and others where it's increasing fast.
I am skeptical of this as well but slot machines are programmable and the house can change the odds.
How do you create repeatable tests in a non-deterministic system? Every time you send the same prompt you get a different answer.
The actual tokens might be non-deterministic, but you could look for proxy measures that are supposed to be invariant. Eg. correctness/performance on benchmarks, "thinking level" on complex problems, etc
This is a good overview of how this is done: https://www.anthropic.com/engineering/demystifying-evals-for...
That's like the entire field of statistics.
I strongly believe that the real Fable is the one we had for a few days in June. Then they nerfed the model a bit after the government pulled it off the market. What we have now is something less, but still good
I also believe this. Fable post-ban was never the same. At the least, whatever system prompt munging or pre/post filtering they did to strengthen the guardrails nerfed it.
question is if they ever let the general public access borderline AGI
It is clear by now to me that Anthropic is constantly trying to find a kind of “auto” degradation perhaps to save money on work it thinks does not require high reasoning. I always use max reasoning and I can clearly see differences between the models when they release and after 3-4 weeks. I think they give a kind of intelligence boost also for new accounts.
Just yesterday I was thinking about gpt-5.6-luna. I made it my default model in Hermes during its fist week of launch. It was just as good as 5.5 which was my previous default. But over the last 2 or 3 weeks I've seen how dumb it is now. I have to be very explicit with it.
For example, I used to be able to prompt "Check the system logs on <server> for...." and it would just figure it out. Yesterday I asked "Did <service> on <server> complete the overnight job" and all it said was "that service is not installed on my host"
I had to tell it to ssh into the server and run journlctl to check it
Anecdotal, I know, but they all seem to be less capable with time.
_edit_ I use the same reasoning level of `medium`
Same exact experience. I worked with both Fable and Sol foe the last two months, daily for several hours, and got used to the very bright, quick thinking, proactive even.
As of last 2 weeks or so both models are nearly on par with DeepSeek4.1 now, which I also use a lot. They're still better, but that difference is not as pronounced as before and, importantly, the frustration level is now on par.
Whatever they're doing will surely drive people to less advanced but predictable, self hosted open models. I sure would rather use DS4.1 with Qwen/GLM in adversarial mode than deal with this b/s I pay significant amount of money.
Me and my friends have been contemplating on getting an Ultra M5 256 and splitting the cost. PI harness is so good now that this is really a viable alternative.
I'm fairly sure it's just luck of the draw if you get put onto a quant'd model or not. I've seen luna xhigh change intelligence fairly drastically on a day to day basis.
Really this is the base problem. You have zero idea where and how your prompt is being executed.
If for example AWS sells you a 2xLarge server there may be some variability in performance but it's going to be averaged out very well.
When it comes to AI services executing your model there is absolutely no information on what and with what settings your model is being executed. Hell, you have no idea if it even is the model you're paying for. Add that models are not deterministic so variability can be pretty large.
This leads to a common set of dynamics that induce cheating behavior in humans. For example, is there a mix of different hardware. Does lessor hardware use different settings? How do you know xhigh is what your prompt ran under. Anthropic has a proven history of running your prompt silently under different models.
This is a huge mess that needs and will be regulated or sued heavily over. Hell, with as many people out there that hate AI it might be easier than one thinks to have a state sue the providers on this and elicit a huge amount of discovery.
& the nice thing about Hermes (since its open source) is you can be reasonably sure that behavior change is coming from the model and not the harness. (probably)
The smart takeaway is not skepticism or snark, but understanding that once the new datacenter buildout starts coming online, cheap and widespread access to even the current frontier models (without strict thinking limits) will blow the economy wide open.
(ie, even a pause in AI training isn't going to stop the train where AI flips the economy upside down, we've barely even seen the impact of the current frontier)
Anthropic is straight up scamming its users at this point.
The question I have is this only happening for a subset of users working in specific areas, such as AI or distributed systems (https://news.ycombinator.com/item?id=48742153), or is this across the board? I am working on distributed systems. Today Fable is mostly unusable. It resembles Opus, so I went looking to see if anyone else is having issues. Sure enough.
I work in embedded systems. I have seen the same thing happening day by day from Opus. Some days it’s okay to use and performs well. Other days I have to correct it repeatedly and remind it of information already in the prompt earlier (before compaction!) and still other times it’s infuriatingly stupid.
It’s a slot machine for what they’re actually giving us behind the opaque paywalls.
Yes, I’m on a business subscription plan.
I have no hard data but I have a strong feeling this morning that something's wrong with Fable 5 compared to Friday evening.
Just an hour ago I had Fable correctly identify an unused method that could be deleted. I then immediately get a diff for an exact duplicate method, and then Fable outputting, "I accidentally duplicated <method> instead of deleting it. Removing both copies now."
The remaining morning complaints that makes it feel like something's off is that it will do a lot of "thinking" for simple things that previously took very little time. And it got very lost and completely mixed up DE-91M predicate names and implementations. Just absolute disaster code that I had over the past months come to generally expect it to do without issue.
Glad I carefully review everything. I think what I need is reliability and consistency. But it feels like picking a model from the list doesn't guarantee that: that the models' "brain" is open on the table and they're screwing with it.
New release of fable and opus 5.5 is pending and Anthropic is reallocating resources. Degradation always happens in transition, it sucks.
Opus 5.5 is being served under opus 5 right now.
Especially with the frequent releases aka version bumps.
Can you elaborate on the mechanism of this degradation? If resources are not available I would expect a request to fail with a message about resources not available. Do they tweak back end model capabilities to maintain service in a degraded state?
Dollars to donuts, they are speculating, and not privy to inside information on the topic.
However, I believe that runtime model quantization is possible with some publicly-available inference engines (e.g. vLLM), so its not beyond belief that the closed labs do quantize at runtime, either to allocate compute, or to nudge users towards a preferred model (e.g. make the incumbent model dumber to push people to use the latest-and-greatest model, or vice versa to ease the load on the latest model, which is typically larger than the old one).
An AI lab will never volunteer the information because it opens them up to lawsuits if they are purposely degrading service and not letting users know.
They can limit how hard the model thinks for a given effort. Suddenly xhigh only thinks as hard as high did, and high shifts down to medium effort, and so on.
They can also serve quantized models. And this has the benefit of practically not showing up in benchmarks at all even if the user experience is obviously degraded.
The other major thing the labs do is silently drop the usage limits. This has become very noticeable for codex users who are suddenly burning through their weekly usage in a few hours.
Yea, if you ever run your own models on a GPU there are a whole ton of different dials you can adjust that drastically affect compute use, memory use, and output token quality, and number of tokens held in memory.
If anyone reading has a GPU it's worthwhile just messing with a smaller model for a bit to watch how the settings affect output.
On what basis are you claiming this?
It shouldn’t be an excuse. They are selling a product and that product should always be within the quality range.
And it's not. A conspiracy theory is what it is.
I have no reason to doubt the claims of the employees at OpenAI and Anthropic who have told us personally multiple times, including here on HN, that they do not degrade the models in order to reduce load.
As for the endlessly long analysis in the OP, it appears it's based on analyzing their random usage data rather than any fixed benchmark. I don't think it makes much sense.
Why would reallocating resources make a single inference run worse in quality?
Maybe they are jealous of Navier Stokes and try the Hodge conjecture with 80% of total compute at the expense of their customers.
I would rather wait in a queue than be routed to a degraded model. And if they _have_ to degrade the models, then I wish they would fucking tell us. Instead, it's "I have a strong feeling".
That we have to guess at this is by far the worst part of the AI era. It feels like a dark cloud over my productivity. It makes my body tense for the entire day when it happens. Not healthy.
They have repeatedly said they do not ever intentionally reduce model quality and do not degrade in this way, and that a model version number is always the same.
But, of course, OP is an empirical claim to the contrary, and I'd be curious to see if anyone (who's been capturing data over these timeframes) can replicate the same results and if Anthropic has any comment.
Every official statement I've seen around this is careful to say that they "don't intentionally reduce model quality", which leaves plenty of room for "we adjusted some knobs and our evals show performance is materially the same".
However, I also agree that I haven't seen any robust data from someone tracking it daily/weekly. The handful of sites purporting to do this aren't even running it enough times to hit stat sig.
edit: someone linked one elsewhere in this thread called AI Stupid Level - they "run 7 trials instead of just 1". I don't blame them. Doing this in a statistically sound manner would cost a small fortune.
I kind of feel "reduce the amount of thinking tokens produced" would fall under degrading model quality.
In any case, I am willing to believe it's possible something degraded, but so far I have not seen any empirical evidence of it since the previous incident with the inference and harness bugs. I lean towards Anthropic probably not intentionally doing anything like this without disclosing it beforehand.
The issue here is you have to think like a lawyer trying to weasel out of making an empirical statement.
For example "We didn't change any settings, but when GPU use gets high the run time of a prompt is lessened. But you must remember this is always in effect so nothing changed at all. This happens occasionally on random prompts some of the time, and when it's busy it happens all of the time".
In someones eye this would fit the letter of the law but not the spirit of the law that you hold.
Sounds like me without coffee.
The Claude models definitely felt more susceptible to moods, like you could leave them for a few hours, come back and it suddenly was unable to do things which it was doing just earlier, which tellingly is never an experience I've had with an open model.
Honestly I lost patience with Anthropic both clearly messing around with things like this and their agitation over regulation. They aren't good actors, and quite why so many blindly trust them with their company crown jewels is a mystery.
Claude Code's prompt cache expires after 1 hour.
Is that from start of a new conversation per conversation?
It's supposed to be for token optimization (https://code.claude.com/docs/en/prompt-caching), but are people experiencing degraded performance when you let Claude Code sit for hours/days and come back?
yes, 100%.
The cache shouldn't affect inference. It is purely an I/O optimization.
If you follow reddit forums for claude code, its common to see people, on the same day, claiming that Opus/Fable is especially smart today, and especially dumb today.
I think people are still not used to non deterministic tools like this, and human perception is absolutely horrible at evaluating trends like this no matter how smart, clever, and experienced you are.
If you have a bank of rigorously tested benchmarks that you run every few days, with enough trials to know what your standard deviation is, and you are getting significant trends over time with those, that would be interesting.
But "I have a feeling" and "Seems like" really isn't a reliable signal at all, humans just can't handle perceiving these things reliably. On top of that changes in your work environment can easily pollute LLMs and change quality of results. Are things getting added to your memory or claude.md files that you don't realize? Is your project growing in size and thus claude is performing worse as more context is needed to work with it? etc etc
The need to have a mental measure of competence for your fellow man is, most likely, a pre-human skill, probably with a dedicated bit of neurons for it. I think the problem is that those instincts were co-evolved with our fellow man, and, as you say, don't apply at all to a more non-deterministic system that, fundamentally, lacks some logic faculties that even small children have (simple riddle modifications, car wash question, etc).
The implication is that humans are unreliable and shouldn't be trusted.
Or humans have certain shorthands when they complain on reddit, but their diagnoses are accurate for the specific context? If my AI does something stupid, am I not allowed to call it out? A NS-solving AI is still capable of not satisfying the abstract thing called the user experience. People have intelligent thoughts without compiling to lean.
OK, you say. Then let's get an aggregate benchmark for "intelligence". That doesn't prove that AI didn't flounder a specific use case that the user requested.
Classic moves: Humans are unreliable, converge to some "objective" benchmark that necessarily will quotient out the special cases, etc. Wonder how we'll be solving these issues in the AGI era - well, if you have an AGI that just replicates itself, dominates everybody because it's a machine and humans are soft fleshy creatures, and agrees with itself, fine. But part of the beauty of human experience is the messy part, and providing value is in the messy part.
In other industries of chance we have regulators that ensure compliance and that the providers aren't cheating.
At the end of the day the highest quality of benchmark tells you nothing if the man behind the curtain is constantly changing variables on you. You have no idea if you're really testing the same thing at all. So when you run your test at the top level on their system you're seeing lets say a 30% difference in quality most of the time, you have no idea if you should really only see a 5% difference in quality if you were running a local model with stable settings.
It’s load shedding. They’re reducing consumption for capacity balancing at your expense. Whenever there are rate limiting storms Claude gets dumber. They also shift capacity for new releases, and Claude gets dumber leading up to it.
Self run infrastructure won’t have this cost but you have to manage the capacity and rollouts yourself, at which point it’s more obvious what’s happening, but the effects will be the same. The not knowing makes it harder, but also harder to plan your own work around.
Correct, but they should explicitly announce this ahead of time.
A general rule of corporate behavior unless they are forced to under duress.
If this is duress of competition or at gunpoint of regulators is up for the population to decide.
Fable is effectively worse than Opus 4.6 now. They severely messed with the model.
Gemini Chat is constantly throwing, "Pro is in high demand right now, a different model was used for this generation," too.
I'm thinking they're all running out of physical resources. It's the DotCom bubble all over again; rollout of the physical infrastructure that's necessary to keep all of the pie-in-the-sky promises will not happen on the timescales that investors can work with, and they will panic when they realize this.
EDIT: And, frankly, I can't wait. I'm tired of the sketchy and dishonest way these companies are behaving.
They want transparency from everyone else but not for them ... you don't say.
This is like shared clouds back in the day where if someone is using the CPU more it impacts you, just pool every one to the same service. There should be an SLA but for the intelligence of these models, otherwise, you are sold fable but with the intelligence of a table.
This is a project i wanted to implement for a long time. It regularly benchmarks cloud hosted models with private benchmarks. Not just openai & anthropic, popular openrouter models too.
Tests their intelligence, not their diligence.
Sadly i cant think of a way to monetize the service. Also if it ever gets famous enough labs would try to game the system, it would be cat&mouse game that i am not willing to waste time on without any monetary gain.
The only revenue model I for this is ads (like AI Stupid Level[0]). Or as a loss leader to get eyeballs to your service (like Margin Lab[1]).
EDIT: I forgot (and am shocked) that HN still doesn't seem to support Markdown-style links.
[0] https://aistupidlevel.info/
[1] https://marginlab.ai/trackers/claude-code/
I mean I think if this is done well, lots of companies would pay for access to that data. Think like Enterprise subscriptions.
Its similar to other data services I see around my F500 company.
I built GitHub.com/adrianco/retort to do this. It’s runs lots of experiments and you can contribute results if you have some spare tokens. You can add your own tests, and it runs Claude, Codex, Gemini, Hermes for local models.
So in 5 years will they lose a suit for intentionally deceiving users? Or is something baked into the ToS by now that allows them to adjust things like this?
I do not know a single senior developer who likes Claude anymore. I do not use their API (Sonnet, Haiku, Opus) anymore and am sending my money to offshore companies such as z.ai (GLM) and QWEN.
The American companies have become extremely deceptive and scammy. I hate Anthropic and OpenAI and can't wait to have a decent GPU at home to use at least Opus or a fable-like open-weight model. This is the current dream of every developer. But NVIDIA is not going to let that happen anytime soon, so maybe China can come up with a GPU that destroys NVIDIA. I pray.
I've followed a few trackers, eg https://marginlab.ai/trackers/claude-code/ , for awhile. For Claude Code the trend, it seems to me at least, is fewer tokens to do the same or better job. Prompt changes, tool ergonomics changes, etc.; I'd be shocked if they didn't A/B every release. Less thinking as measured by tokens isn't necessarily bad if you can get the same results by making it think about the "right" things or structure. They obviously screw up sometimes, and I've always been suspicious with hidden tokens, but I haven't found evidence quality intentionally degrades over time.
Same. With some 500 hours of usage in just my project at home, across both the $200 Claude and Codex subscriptions, I have not once encountered a situation where I would have attributed unsatisfactory results to a degradation in the model.
I've seen bugs in the harnesses, sure, but never anything in the actual model where I could have said with any certainty that it's not just regular variation or me having a bad day myself.
No idea where people get the confidence from to make such claims every other week.
These analyses are much better than these Twitter charts.
I don't think anyone is reading the details for the Twitter post because it was not an actual benchmark. They did a post-hoc analysis of their logs from day to day.
Their random collection of prompts for each day is not a benchmark.
The site you linked is a much better example of a real benchmark being repeated over time.
The Office of Weights and Measures exists because, long before any of us were born, in 1836, companies were up to shady shit and consumers were paying for inconsistent products. I.E. Being scammed.
AI companies should be subject to the OWM like any other company that sells a product that varies in weight. Perhaps when a sane administration is re-elected; one that can read history books and comprehend why our regulations exist in the first place. Or have even a semblance of respect for its citizenry.
Petition to rename them to the Office of Weights and Biases, haha.
THIS EXACTLY.
The only regulation that we need right now is the model that's on tap
Anthropic terms of service:
You're not buying a gallon of milk or a pound of flour. You're buying hosted software that the host reserves the right to modify.
You are not buying something and expecting it to be what's on the tin? Aka what the benchmarks show?
I doubt that would change the perception. Every model release is followed by accusations of nerfing.
There are several projects that repeat benchmarks on published models. None has ever found significant fluctations
Here's one example https://marginlab.ai/trackers/claude-code/
Fluctuations of a few percentage points are to be expected and should not surprise anyone who knows how LLMs work.
This Twitter analysis of Fable 5 is not that at all. They analyzed their coding sessions and blamed all of the fluctuations on Fable changing. They then compared to ARC-AGI-2 questions as the benchmark for thinking tokens and tried to stir up anger that coding turns don't produce as many thinking tokens as the ARC-AGI-2 problems.
This page has been in 'New model — collecting baseline data. Degradation detection paused.' state for months now. It seems to never say 'degraded'.
If you look at the graphs, the latest benchmarks are showing a pretty significant dip, and they match pretty well with some horrible experiences I've had in recent weeks. You can see token usage steadily going down, matching exactly what the author measured on his own.
Click the part at the end that says "View historical performance". They wait to collect more data about a new model before adding it to the overall charts.
The overall solution rate continues to climb when new models are considered.
The y-axis is amplified to make differences look larger than they are.
Hover over the dots to see the confidence interval. A 1-2% change means nothing.
I stopped using Fable long time ago. It's worse than Sonnet. Opus is not much better.
This cycle of new model running at full quantisation and then nerfed few days / weeks after premiere should be called out. Anthropic should also drop the adaptive reasoning scam.
If I pay for Fable, I should get full, not nerfed model at honest pricing.
Regulators should investigate them.
OpenAI is no different. Astra has basically the same problem.
The ROI just isn't there. It feels like Fable is in the same place Opus was early last year; at best marginal improvement that's barely noticeable over the lower model, for 10x the cost. I'm sure it'll take over as the workhorse as Opus did once they get it down, but right now it just doesn't make sense
It's not really 10x the cost though, with the low cost of cached read it's more like maybe 1.2x the cost.
Makes sense, no? Test time compute is something you can vary, so it makes sense that you start covertly reducing it once the model has already made it's splash.
Could there be a benefit to releasing a new model, slowly dumbing it down over a couple months, then releasing a new model that’s marginally if at all better than the original to create a perceived improvement when in reality there isn’t really one?
For an industry that’s stagnant in progress yet relies on new frequent releases to survive (non-progress being an existential risk), this could make sense.
I have no idea if that’s what’s happened, I completely pulled it out of my butt. And I have no idea is the actual frontier is stagnating.
Exactly what I am saying for months now. And it's exactly the reason why I am shifting to open weight models now. Just bought myself a 2x DGX Spark Cluster. Will run Qwen3.8 Flash Next on it, maybe Qwen4 when it comes out.
Not only do I have full control over quantization and inference, but also will I experience a constant level of quality. It won't be frontier. But it will be stable, and that's enough reason for me to switch. Also I will likely save some money on subscriptions.
Unlikely. The $200 Claude subscription allows for billions of tokens/month, and that kind of hardware will take years to amortize.
There could be gym logic at play. Hundreds signed up, 20 people actually exercising. Though it's probably more likely in the lower tiers.
I wouldn't be so sure. The generosity of the subscription plans has declined GREATLY over the past 6 months or so. They are likely trending towards api pricing parity. In which case, having your own hardware makes sense if you can utilize it well.
Last time I estimated it was like 30 years to pay back. I doubt the hardware will even last that long.
Last time I estimated, it would only take 3 months to pay back because the 1TB Mac Mini running Qwen RSIingly developed ASI and made infinity dollars off of crypto and I got put in jail by the SEC.
Where'd you get 30 years from? Show your work.
I would like to subscribe to your newsletter.
I have 2 x ChatGPT Pro 20x, Claude Max 20x, and Kimi Vivace. It's about ~12 months payback for two units and the cable.
The problem is they can't fit any frontier level open models.
flash next is good, I've been running it for like 2 weeks now and it's pretty solid, hope you like it and it meets your needs. I still lean on Claude and codex a fair bit for harder stuff, but I'm rapidly moving towards 2x $20 plans instead of 2x $200 plans
I don’t know what people do with the open models but having tried a lot of them I just can’t make it make sense. they’re too dumb and it effectively makes them useless (to me). it’s probably worth being honest about the low ceiling here.
Qwen3.8-Flash-Next seems pretty much auto pilot when I get it the right context.
Perhaps reverse the question: Are your build/construct requirements just really counter-productive to how LLMs need to understand things?
I've found constructing the code, writing the tests, adding the docs; then running through them gets most of the way there.
I've also found that making a simple obvious edit is a useless endevour when the LLM is primed for the long context tasks.
So, again, the question is reversed: are you over reliant on the LLM to do even stupid simple likes like editting a css variable?
Serving compute is their main value prop
Yet… even Altman called out Anthropic for serving dumbed down models.
Shits weird man
Every SOTA model I've used at launch uses deeper, longer inference then gradually turns down over time, until the next model comes out which seems to be trained on some new data, but mostly performance due to deeper longer inference for another period.
I have not been attributing it so much to malice, just that all the major cloud vendors seem to be running at full capacity, and can't build new datacenters fast enough. I just kind of assumed that as they got busy training newer models, that they allocated less resources to handle the existing systems, because they aren't able to get more capacity right now.
I’m not sure why this point keeps coming up — if your service/product is so popular that it’s capacity-constrained, then the answer is to raise prices, not degrade service, because the demand should be inelastic.
This really depends where the load shedding point is.
A very small raise in prices may cause a very large loss in customers that you risk never getting back.
For example if customers figure out that the Chinese models are just as good, they are gone because they are so much cheaper.
Raising prices also has second order effects, like consumer and business expectations around how widespread the tech can be. Valuations depend on it being reasonably affordable to roll out on a much more massive scale than today. If people get the impression that it seems too limited to very rich people (200 is affordable for a North American / Western European professional), the impression about the trajectory will change.
The Opus 4-6,4-8,5 arc is exactly this. As one person commented in here, opus 5 is a terrorist. This is undeniable. Opus 4-6 was awesome. 4-8 was worse behaviorally but produced better code.
Fable seems to be following the same enshittification arc of other Anthropic models.
Generally OpenAI seems to be taking the opposite approach with an increasing improvement over time. As sad as I feel to say this, open ai seems to have the right strategy. Making your product worse over time rarely plays well with customers. At this point it feel often hard to justify using Anthropic for anything. I generally like Anthropic better as a company and they really had the initiative and advantage and customer good will, then proceeded to squander it faster than a cigarette company or the Sacklers could have.
On the other hand, New Coke was a resounding success. Well, it, itself wasn't, but in the aftermath, Coke outsold Pepsi 2:1.
This sounds similar to rumors about how SSD companies work. First they would design a new drive with better performance that everyone uses to benchmark against other models; then slowly change its parts to worse ones, either because they are cheaper, the originals are no longer available, or whatever reason
There must be some benefit if all the providers are doing it independently.
GPT5.6-Sol on Max thinking just became regarded as of a few days ago.
The boosters will tell me it’s my fault for using such an old, cheap out-of-date low quality near useless wish.com model (that was SOTA and better than human coders one month ago).
The cycle repeats.
Again, I’m out of my element here, but isn’t the entire industry dependent on “new better releases frequently”? If so, and if no one has made any meaningful breakthrough, might they all pursue this kind of deception just to stay afloat/“competitive”/relevant?
Thanks for your insight
Not unless your competitors do the same, or else you will only be perceived as falling behind others.
...releasing a new model that’s marginally if at all better than the original...
This isn't what we see in benchmarks.
Yep, that's what they've been doing for a long while now. Also the amount of tokens you get per sub varies drastically from month to month. Needs to be regulated.
Yes, the AI technology is known primarily for how stagant it is.
You can serve Fable from a cloud vendor (like AWS, Azure). They have frozen versions of the models, so likely this should not be an issue?
I would do a test to verify my suspicions.
This wouldn't explain progress on benchmarks (including closed sets), or the fact that newer models are providing solutions to major math problems that older models cannot.
Far more likely it's about reducing costs.
* Release new model that scores an arbitrary 100 on a benchmark
* Get everyone to talk about you as the first model to ever score 100 on the 100benchmark.
* Tune it down over time so that you end up only scoring 75 on the benchmark and people get used to it, gaslight them into thinking it never changed or that it's just a harness problem, they can't run the old version locally anyways to verify. This also cuts your costs in half. Your gross margin on API calls goes from 70% to 150%.
* Release new model that scores 120 on the benchmark and advertise it as 50% better than the current model, while it's only in practice a minor increment. Everyone praises it as the second coming of Jesus Christ.
* Get everyone to talk about you as the first model to ever score 120 on the 100benchmark.
Bis repetitae.
Why can't the models be benchmarked again after a few weeks/months to confirm this (likely true) theory?
I imagine some people have their own personal in depth benchmarks they could do this for.
Where?
I see so many accusations of this happening and it's so easy to check, but nobody ever proves it.
but there is a gap between benchmarks and user feel.
Opus 5 came out with better benchmark results than Fable, but it really did not feel better to use at all.
This is a good point I hadn’t considered, thank you.
Is there any training variable here? For example, can a model released in October perform better on the same benchmarks vs its predecessor released in July just by virtue of training on newer data that was made available on those 3 months?
Sorry if it’s a dumb question, I don’t really know much about the topic.
Nah its because they cache and preprocess requests by dumb models and send them too often to another dumb models instead of the top tier model.
you mean like a Shepards Tone (https://en.wikipedia.org/wiki/Shepard_tone); i wouldn't doubt they slowly tweak quants to try to eke out.
there's also probably load balancers that downgrade models during high use.
Check gpt I think they recently started taking the same route
Don't they continuously tweak the models post-release?
Is this something specific that shows up in the wire log, or is this the author's intepretation? The fact that Claude Code versions change over time in the test is suspicious. Anthropic has stated in the past that the underlying model behavior does not change over time, but Claude Code will change from version to version and this is expected. So if it's just Claude Code more aggressively tuning some knob in its requests, that's a pretty different thing than the underlying model changing.
They posted a long document explaining it all https://x.com/Lon/status/2101034933284417614
They're not measuring a fixed set of questions. This was post-hoc analysis on whatever prompts they were running each day.
Anyone can understand why it would go up or down depending on the work they're doing that day. This analysis is silly.
It's easy to imagine this only happening for subscription accounts rather than paid API usage. Any data on this?
You should read this person's full article to understand what these charts are showing https://x.com/Lon/status/2101034933284417614
If you thought this was a repeated test of the same problems showing fluctuating performance, it's not. They set up a MITM proxy between Claude and the servers and ran analysis on the work they were doing.
So those ups and downs in the charts, which they plotted with sub-daily resolution, are just as much a function of their work changing from day to day. It's like plotting the miles per gallon of your car and blaming the gas station when the number goes up and down, without admitting that some days you drive to the grocery store on surface roads and other days you drive up a mountain on the freeway.
The analysis (which feels very vibe-slop) gets worse from there. In the second half they take thinking token counts for ARC-AGI-2, thinking problems designed to stress LLMs, and compare their average thinking-tokens-per-turn counts to that!
If you don't realize why this is so flawed: ARC-AGI-2 is a benchmark meant to collect problems thought to be extremely difficult, nearly impossible, for LLMs. If your goal was to cherry-pick a mislead example which would produce the highest number of thinking tokens, this is it!
Your daily coding work should not be producing a proportional number of thinking tokens on every invocation while it reads through some source code or edits a couple lines in a file.
You don't want to maximize the number of thinking tokens. You want problems solved accurately with the minimum number of tokens.
Confirmation bias runs deep on this topic so I assume few people read the analysis before posting, but as far as experiments go it's basically useless. Are they changing something on the server? I don't know, but this analysis isn't useful for answering that question.
Thank you for your kind words, Aurornis.
Yes, this is my production corpus, across 65 usage days, two subscription accounts, three machines, 25 project groups, and 213 sessions, across 43,261 invocations and 7,583 turns. Use your own data if you want to prove or refute what was seen in my corpus.
The "ups and downs in the chart" were not plotted with sub-daily resolution. Specifically, the two-month temporal chart uses a 3.5-day Gaussian bandwidth which is meant to reduce short-term noise while retaining broader changes.
Additionally, a separate episodic analysis identified multi-day changes in delivered thinking. And those episodes were predictive of held-out work. The more projects pulled into an ensemble, the more predictive they were of delivered thinking tokens for held-out projects during the episode.
The point of the benchmarks is to establish a baseline for what thinking-token counts one should expect from specific effort levels using published numbers, not what every response should be delivered. If you looked closer, you would see that P90 invocations were still delivered 13x thinking tokens below that level.
So you don't have to provide a generous interpretation of my workload if you don't want to. Remove all of the zero-thinking token responses, redistribute those samples across the distribution, and then tell me if it magically shifts right and starts delivering anything close to published numbers. Only -46- out of 36,374 July and August invocations even broke 16k thinking tokens - only 0.13% of the total. You are welcome to present what percentile you think is a fair comparison to make here.
If you would like to denigrate a month of my time as vibe-slop, that is your prerogative. You can even be dismissive of my workload, if you want, even if my background should tell you otherwise. But if you want to knock a month of someone's time, do it with your own data to at least help move the conversation forward.
I don't think you understand. What you posted is highly dependent on your corpus. I can't "refute" anything because it's not available and it's the major variable in the experiment.
I think you're missing something from that first sentence, but I assume you're talking about the comparison to ARC-AGI-2 published thinking tokens?
It should be blindingly obvious that you do not want your thinking token counts to be as high as a benchmark that was designed to push LLMs to their limit.
What point are you even trying to make?
Again, you don't want invocations to be burning 16K thinking tokens except for rare problems that 1) must be solved in one step and 2) are designed to be entirely self-contained thinking in that step.
You're trying to compare development work to a benchmark that encapsulates complex thinking into a single step.
Coding work is iterative and works in incremental steps: It runs commands, reads more files, checks the web. Thinking tokens should be low for your turns.
ARC-AGI problems have an input and an output. They look like this: https://arcprize.org/tasks/b5ca7ac4 They have more thinking tokens because that's the entire state. They get one output and it's constrained.
It is fair to discuss a published analysis. Saying that only people who bring their own month of equivalent analysis (which conveniently would take another month to produce) are allowed to critique it is just a cheap trick to shut people down.
If you post big claims, they are open to analysis and review by others
After reading what you had to add to this discussion, I have only two things to leave you with:
1/ if the point of setting xhigh or max effort on a "reasoning model" is -not- to have additional reasoning tokens applied to the problem, then I fear we are all using AI wrong 2/ the decorum with which you "review" someone's work in public is entirely your choice. the only "cheap trick" on the internet is being a pseudonymous ass.
You keep moving the goalposts. The core flaws in your analysis are that you assumed the variation was 100% server side and didn't admit that the inputs were random and different every day, and that you tried to compare to ARC-AGI-2 as a benchmark.
Comparing ARC-AGI-2 thinking tokens to agentic coding thinking tokens is as misleading as it gets, because these are completely different use cases.
Please stop and think about this for one second. Do you really want Anthropic to spend 30K thinking tokens on every input, just because that's what ARC-AGI-2 problems required? What would your inference bill look like if this was the case?
The premise of your ARC-AGI-2 comparison is broken.
Ironic to accuse someone of cheap tricks as you pull out an ad hominem insult after someone explains the flaws in your reasoning.
My points stand: You can't claim this is a chart of Anthropic changing the server when you were feeding it random input every day and plotting the output as if the line should be flat. You can't compare agentic coding to single-turn ARC-AGI-2 problems.
There's a lot of chatter on other forums and Reddit about the same thing happening to Astra over the last couple of weeks.
This is exactly what I have been experiencing and the difference is night and day! We have been advertised and given a taste of what Fable was and after that been served an exteme watered down version. It is so bad that sometimes chatgpt feels better.
Oh boy, a new "nerfed model" conspiracy theory, never seen THIS before
The theory isn't new, the proof is. Do you have problems with lon's methodology?
Opus 4.8 was smarter and possibly 10x faster than Opus 5, too. They are dumbing things down on purpose. I am praying for open models to become at least as smart as Fable soon so we can ditch these shitty, lying companies.
I was rooting for Anthropic 2 years ago, but now I have become an extremely bitter customer. Just another version of OpenAI, if not shittier.
The model improvements value are at the plateau of utility right now, peeling out small gains which is pretty “meh” in terms of business value
at this point frontier companies are just selling upgraded harnesses and tool calls with the rest of us