It’s a really good model. Over the past few days, I give Opus some general directives to basically speed up our CI, and telling it I care both about billing minutes and wall clock time. I told it to create a plan after analyzing everything in our CI, run the plan by a Fable subagent, and then focus on low-risk, high-reward changes.
9 hours later, I had 12 PRs ready to be merged, and the net result is CI time has dropped from ~10 minutes to ~4 minutes, and billing minutes have dropped around 60%. Less than an hour of my attention.
Every time weird stuff happened this week it was because the model choice in VSCode got set back to “auto” and some other model was trying its best. 5.5 is what I just set it to. Even Fable feels worse for my use cases.
Even Anthropic rates Fable lower than 5.5 on pretty much all benchmarks.
"Why does Fable even exist" is a very very reasonable question right now.
You are making the mistake of classifying models on a single linear axis, or even a multi axis basis set of all benchmarks. That just isn’t true. Each model is unique in its skills and capabilities and the way it approaches problems, in a way that is not represented in benchmarks. Fable is better at reviewing things. I don’t know how to explain it well but it is true. I trust Fable to do thorough reviews (sometimes too thorough) and to present its information in a dense but ordered way. Its output is equivalent to what you used to get from security firms doing code reviews. Having Opus do the work, and have fable do reviews (of the plan and implementation) is a good combo.
It's a class of model not a static one. There'll be Fable 5.5 that's even better than Opus 5.5.
Although we never had a Claude Opus 5.1. Fable went 5 → 5.1 and Opus went 5 → 5.5.
I assume Fable 5.1 is the first re-tuned (is there a better term for this?) version of Fable 5 and Opus 5.5 is the first re-tuned version of Opus 5, and maybe the Opus one just came out better for some reason?
Because Anthropic releases their different model level's at very different points in time, they seem to always have one model that is by far an away the best to use for everything. Haiku 4.5 is almost a year old. Sonnet is fine, but idk if it has any real benefits over Opus. It's only been since Fable has been released that you get to choose between Fable and Opus, but not with 5.5 there is no reason to use Fable.
I feel like instead of releasing fable, they should have released it as Opus 5, then their next Opus release they would call Sonnet, and their next Sonnet release they would have called Haiku. I don't know if their pricing structure would have been able to support that, but Anthropic has always been the least competitive regarding token pricing.
I would also say: I think this works great because the goal is well-defined and measurable.
I’ve also used Opus 5.5 on some hill-climbing, and a lot more steering is required here, because … eval is hard.
Agree Opus 5.5 is incredible and efficient with Claude Max Usage.What a jump after the writing slop you got from Opus 5. I had moved to using Fable for my orchestration workflow mainly due to the communication issue (I think Opus 5 was capable enough but spoke in riddles so you lost confidence quickly)..With 5.5 it needs less steering now and communicates well, and I have had the same CC session running for the last week (obviously compacting with durable plans etc as the post), with it PM'ing my home built agent orchestration of the other coding agents(antigravity, codex, pi etc) and making decent decisions and all the recommendations are normally usually good.
9 hours?!
Yes. It spawned multiple subagents to run different experiments to benchmark a lot of different things, reviewed CI logs from past runs, etc. In the end, there were changes to what/how we cached, various code quality checks, speeding up test runners, and many other things.
I dare not ask about the cost, having burned $60 on a task running for 1h 16min once.
I’m on the $100/month subscription; this session took about $500 in token-equivalent costs.
(Note that it wasn’t all Opus 5.5; I have a setup that uses Fable 5.1 as an advisor, Sonnet 5.5 for mechanical changes, etc.)
God I hope the prices drop quick. Once they stop subsidizing it these kinds of workflows will be unaffordable for anyone who isn't already wealthy
An insane amount of compute manufacturing comes online in 2028. Compute is a commodity. It's not going to stay expensive for long.
Assuming this isn't some toy CI a 60% drop in billable minutes will make $500 back pretty quick. Github is wildly expensive.
They have dropped, in Chinese models.
Pricing is dropping quick. Inference is so cheap, I think they are losing a lot less money selling subscriptions than you think. It might even be more expensive managing the load, than actually selling the tokens at subscription prices.
We are seeing with OpenAI, allegedly through their new pricing scheme, as intelligence and model efficiency increases they offer the same throughput while advertising 1/2 as much usage, letting Astra consume more usage, essentially only being available to those wealthy enough to afford it while still offering essentially unlimited Sol and Luna to their subscription tiers.
Also if you're cache hit rate is high enough a billion tokens tokens from Deepseek 4.1 Flash costs less than $15.
Subsidies are a lie planted by Misanthropic and ClosedAI to milk their users and let them think it's the other way round.
Inference is highly profitable business, even for third parties with much less resources and expertise.
Does it resume automatically on higher subscriptions?
I'm on a $20 plan and it never auto resumes. I have to go back in and type out resume or click a button.
Instruct it to arm a monitor (every hour or so) to wake him up in case of quota or api issue.
Interesting how the French call Claude a "him" and not an "it", as French and many other languages don't have a word for a neuter pronoun.
If you compare the cost to the price of dinner or whatever else you spend disposable income on, it can seem high but if you compare the cost to employing an engineer (don’t forget costs for payroll taxes, office space and equipment, etc) and consider the fact that the models often seem to be much faster than even expert humans, the costs don’t seem so terrible.
It’s great, but you still need to know what you are doing, not just the goal/s. I built a platform years ago from scratch, and now I am remaking it with more features and more polished design, I know exactly what needs to be done to tiniest details. The first prompt was very well detailed about the architecture and how everything should work, after an hour work at Xhigh, it did create the blueprint artifacts that I asked for, then I spent 3 days reading every single thing and writing notes, turned out it made the system overly complicated without adding extra value, plus I can see how some of the architecture design will be potentially a security risk. So after few days I fed my notes, this time took 4hours and 1M tokens! Later I spent more few days reviewing and writing notes, it was closer to what I want but still made architecture errors, the third run took around an hour and finally made it how it supposed to be, although there are still more notes on non critical stuff. So I don’t think we are yet at the stage where sitting goals and some high level is enough to produce quality results.
To back this up we have a discord chat for the board game terraforming mars where the agent takes input and vibe codes an open source implementation of the game.
https://tfmbot.com is the link (discord and source links on the splash screen).
The results are fucking incredible to the point where people in discord are stating "I'm surprised this is working so well". I am too.
I feel like there's a group online that missed the boat. Anything negative towards AI capabilities is still upvoted but I've been in the industry for over 25years, highly respected and can't fathom the "AI dumb lololol" type of comments i see on HN. AI is superseeding all other ways to develop.
I'm restoring a game I played as a kid, that I couldn't reliably get to even start on modern Windows. The skill and speed with which Opus 5.5 got it running, while patching a bunch of bugs in the binary along the way (only some of them I knew about), has my jaw still on the floor - and few hours in, I already have whole campaign mapped out as state machine graph, and we're upscaling graphics now.
Pretty sure no one on HN says AI dumb
From just this morning i read this thread: https://news.ycombinator.com/item?id=49946321 about a linux distro no longer allowing AI code and the comments are mostly along the lines of "This will be great for maintainability, AI can't code any complexity" which is essentially what I'm getting at here.
AI writes clean code and can do so in a very maintainable way honestly.
Meh... There's a reason Opus 4.6 is still an option.
Pros know these are lower cost models.
I do like Opus 4.6, but I think 5.5 on medium or low is a better value. I have to steer 4.6 more and build more scaffolding around the tasks. 5.5 just does what I ask. Visual spatial reasoning greatly improved in 5.5 as well.
>> It’s a really good model.
In the meantime, I have cancelled my Anthropic subscription...
I have a simple test that I have been running iteratively across the SOTA models from several vendors, including one Chinese vendor.
I start with some code produced by an Anthropic SOTA model...let’s call that Code A. Then I get Code B and Code C for the same task from models by two other vendors.
Then I ask each model to review and critique the other proposals.
By the end, both the Anthropic model and I usually run out of arguments... against them and agree that proposals B and C are better.
Claude then always asks whether it can incorporate the code or ideas from B and C into its own solution...
It's not even funny any more. Chinese model, Chinese vendor, Chinese, Chinese... Did I say Chinese? Chinese!
Nobody in his right mind will use a Chinese clone when you have models like Opus 5.5 for peanuts.
Yes ...I was so impressed I cancelled my subscription. I could not stand all the winning. I offer cheap hourly rates of $1000 for debugging AI slop.
Contact me at : prompt.plumber@gmail.com
> Nobody in his right mind will...
let a few valley elites decide how humanity can use this technology
open and transparent is the way, China is showing how
I’m rooting for open models, but SOL 6.1 and Opus 5.5 are absolute workhorses on a $100/mo sub. I share your fears, though, and really hope an open model catches up and can somehow compete with the subscription prices of the big 2.
I have workhorse models, spend far less, the model matters less than people like to claim
there's no money long term in being a token vendor
The biggest revelation from using open weights, because the vendors offer most of them up, is how useful using multiple model families is. Regardless of open or closed, if you are only using one family like Ant or Oai models, you're leaving a lot on the table. A harness like OpenCode will enable you to use different models in one session, or more specifically different subtasks when doing long running teams.
> Nobody in his right mind will use
Nobody AMERICAN in his right mind will use... Wait, actually a lot of them will.
But for me, as a non american, non chinese person: I'll use whatever the fuck is the best and cheapest for my task, because that's how fucking Capitalism works.
If that means that a (proclaimed) "communist" country cleans the carpet with the self-proclaimed land of the free: so be it!
[dead]
Is "wall-clock" an actual term you used before Claude? I had never heard it before the model used it and I can't stand it.
It's a pretty old term, to distinguish from e.g. CPU time. This was in common usage even 30 years ago.
Example from 15 years ago: https://stackoverflow.com/questions/7335920/what-specificall...
Trying to make us feel old? Very common term among people around my age and higher (40+). Please don't turn "I've never heard that expression before" into "must be AI saying it".
It's a standard term and has been for ages. It distinguishes end to end time vs eg the amount of CPU time an individual process uses (which excludes time spent waiting for the system or time when the process was otherwise not scheduled on the CPU).
As old as time.
https://ss64.com/bash/time.html
I've used wall clock for many years, normally when compared to CPU time when talking about parallelizing some process.
CPU time might go up while wall clock time goes down
“Wall time” is a pretty common systems term (you see it when comparing total runtime to kernel time, for example). I wouldn’t have indexed on “wall clock time” or other variants as an LLMism.
I've heard that term for years before LLMs
Wow...it's super common. For example, timing a program you can get user CPU time and then wall clock time, which can be two very different numbers.
Lolwut? You seriously have never heard anyone say this before?