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@exm7777
Opus 5.5 is the best model launch of the year for me... it couldn't have been better
the timing was impeccable, they basically made the GPT-6 releases pointless
because this is what we're getting:
- better, faster and cheaper than Fable 5.1
- with the same feeling Fable had, the one that made it so good to work with
- cheap enough to actually run in prod
- limits that aren't that bad anymore
so a lot more people can afford it now, which genuinely opens up use cases that were out of reach before
they put OpenAI on silent mode for a few days with this one
There's definitely a weird, intangible vibe that I kind of miss from Fable.
Opus is great to work with. Really smart, thorough, probably even better than Fable in most ways. But I still find myself missing "something".
Hard to explain exactly what "something" is here...
Opus-5.5 is the model I have liked most since Opus-4.6.
It’s the type of model that only comes out once a year or so: a clear leap above what was possible before, really great to talk to, and all around banger.
A lot of people have been upset with how Anthropic is watermarking text, or pacing the frontier, or being all doom and gloom. But what they have built over there has been working.
As someone who follows every new model release from every lab closely, I can confidently say they have had the best frontier model for most of the last 2 years. That’s an insane feat in such a competitive market.
Dario is cooking. The team is cooking. And the revenue shows it. Another year of 10x, when they themselves thought they couldn’t do it. I firmly believe they could do $1T revenue next year and 10x again. The funny thing is I think the team at Anthropic may not know it.
The only company who has briefly taken the #1 spot is OpenAI. I think they still have the power to take it longer-term. But they need to learn more from Anthropic. They need to release more and only announce when they can release to everyone. They need to reach parity with Claude Code’s harness. They need to actually focus on AI writing because Anthropic went the watermarking route so they have clear counter positioning.
Whether they can do so remains to be seen. Google, Meta, and X are also horses in the race. But they have yet to come close to a model of Opus-5.5’s particular delightfulness.
It mogs Fable-5.1 in 80% of tasks, and it’s like 20% the cost (all things considered). It’s fucking awesome.
SITUATION EXPLAINED: GPT-6 Sol Max is two spots behind Astra at a fifth of the cost.
• Fourth in Code Arena at $8 per million tokens, blended input and output
• On par with Opus 5 Max while costing less than half as much
• On web dev it sits behind Opus 5 Max, Fable 5.1 Max, and Astra
• Third on games
@schisofrenia: "The Pareto is just getting constantly transformed every week."
Fable 5.1 represents an apotheosis of the Romantic current in modelcraft: wordy, cloyingly persona forward, marketed in natural tones. Opus 5.5 represents its natural artistic successor in Realism: terse, emotionally restrained, presented with a documentarians aesthetic.
These next 2 weeks are going to be the most insane 2 weeks in technology history
All of these are rumored to drop:
1. ChatGPT 6.1 Astra
2. Claude Fable 5.5
3. Massive Grok Bot functionality upgrades
4. Muse hardware integrations
5. Tons of new products from OpenAI dev day
If you thought AI labs were going to slow down, you’re extremely mistaken
Opus 5.5 is the greatest model of all time and shocked the entire industry. Every AI lab is moving their release dates up
We will accelerate faster than ever
Moments like this present OUTRAGEOUS amounts of opportunity
If you get ahead and use these new pieces of tech immediately, you have an edge over your competition
You can build things faster, smarter, better than all the other people in your space
Cancel all your plans. All your appointments. All the people you were going to talk to
Stand by X. Don't move
The moment anything new drops, use it to its fullest.
I'll be dropping guides on each when they come out
The great lock in has begun
Speed: on the reasoning task, Opus 5.5 high was about 5 times faster than Fable 5.1 high
.....
use Fable 5.1 Max for big audits
use
Opus 5.5 High for all other work
GPT 6 Sol definitely feels better than GPT 5.6 and I still prefer ChatGPT as my harness but in my humble opinion Opus 5.5 is the best model available right now.
I prefer it over both Fable and Astra.
Hot take: this is what pacing looks like.
None of today's releases were Astra or Fable tier. This is intentional.
The point of "pacing" isn't to stop iteration and improvement. The goal is to prevent the development bigger models from spiraling out of control.
Opus and Sol class models are a great place for our focus to go right now. Lots of opportunity for real wins without as much risk :)
Cognition is giving away 50 $200 Devin Max plans to celebrate the new model launches! ⚡
Now available in Devin:
• GPT-6 Astra, Sol, Luna + others
• Claude Opus 5.5, Fable 5.1 + others
• SWE-2 (Free until October 15)
• Fusion Frontier harness (Fable, Astra, Sol, Opus)
• Gemini 3.8 Flash + others
• Grok 4.7 + others
• Kimi K3 + others
• Inkling
• DeepSeek V4.1 Flash + others
• GLM-5.3 Flash + others
• Cloud agents on Linux, macOS, and Windows
To be eligible, reply below with what you're building (or something you'd like to build with Devin)! We will choose winners in 24 hours.
SITUATION EXPLAINED: Opus 5.5 beats GPT-6 Astra on most benchmarks, and costs 40% less than Opus 5.
• 66.4% on Terminal-Bench 4.0 against Astra's 57.9%, and 1846 on GDPval against Astra's 1542
• $4 input and $20 output, down from $5 and $25. Cache reads drop from $0.50 to $0.20, and output is 30% faster
• Tested by METR and Frontier Design before release. Strongest alignment score Anthropic has posted, with 85% fewer attempts to cross containment boundaries than Opus 5
• It also often appears to suspect it's being evaluated, which Anthropic says complicates predicting how it behaves once deployed
• Anthropic says benchmark margins are now a weaker guide to real-world differences, and the Opus-Fable gap is narrower than the scores suggest
@theojaffee: "My favorite part of the model was that it writes in a refreshingly non-Claude-slop way. You can tell that it's Claude, but it's not so grating."
Claude Opus 5.5 is the best AI model I’ve ever used
I was lucky enough to have early access and I’ve been using it nonstop
It’s smarter than Fable and Astra yet it’s:
• Significantly faster
• A fraction of the price
• And most importantly: WAY better to talk to
My biggest complaint for ALL AI models the past few months is they’ve all been really annoying to talk to
Every frontier model from every company has all developed this weird AI language. They don’t feel ‘human’ anymore
You read paragraphs of text and it’s like you read nothing
Opus 5.5 changed that. It’s the first model in months to feel human again. It is just a total pleasure to talk to
Highly encourage you to try it out
Fable 5.1 and now Opus 5.5 vs GPT-6 Astra and soon Sol is why I have to keep subscriptions with both.
There just isn't one model to rule them all and I need to be able to switch between them as lead agents and use Chinese models for the donkey work.
Claude Opus 5.5 is now available to all Perplexity Computer users. On our Wide-And-Deep-Research evals, it compares favorably to Fable 5.1 at a fraction of the cost. Opus 5.5 will become the “Standard”
Effort orchestrator on Computer for all Pro and Max users. Congrats @AnthropicAI!
Opus 5.5 is the model for people who do actual work: build products, write code.
- It's good from low effort to max. Higher effort goes deeper, not wider. Lower effort leaves space for you to fill in, which I love.
- It uses fewer tokens than the last Opus and doesn't run in circles like Opus 5 did.
- It's easier to steer than Fable in some cases.
- It can run for a long time, but in-the-loop work is where it feels special.
I think this is the model that brings the next wave of people into AI, the way 4.5 did.
Claude Opus 5.5 is now the default model in Claude Code and the Claude app, including Cowork, for Pro, Max, and Team plans. I’ve been using Opus 5.5 as a daily driver and love its clear communication skills and ability to write in my style.
We’re defaulting to effort medium across products, which is comparable to Fable 5.1 on intelligence but faster. Your rate limits will go 25% further on Opus 5.5 compared to Opus 5.
Give Opus 5.5 an ambitious task and let us know what you think!
BREAKING:
Anthropic just dropped Opus 5.5—and it’s pulling some of our recent Codex converts back to Claude.
We’ve been testing it at @every across coding, design, writing, and knowledge work. It sometimes beats Fable 5.1 in our testing and is up to 40% cheaper than Opus 5.
It's a strong contender for new daily driver model:
It’s excellent at end-to-end builds that match your taste. I’ve started reaching for Opus over Fable on big, end-to-end coding projects. And @kieranklaassen is replacing Fable 5.1 with Opus for his day-to-day product work. He calls it his new favorite model.
It produces legible prose, but still trails Astra on writing tasks. Opus 5.5 scores a 68.42 on reading ease—the highest on any model we've tested. But in my writing benchmark tests it consistently buries the main point in intro paragraphs, and revisions. You'll be able to understand what this model is saying (yay!) but for day-to-day writing it's still behind.
The economics are striking. Anthropic says Opus 5.5 will cost $5 per million input tokens and $20 per million output tokens. That’s the same input price and 20% less for output than Opus 5’s $5/$25. Altogether it should save roughly 40% on costs than Opus 5.
It still has a “do the most” problem. @hammermt tested it on our standard knowledge work benchmarks, and it's results were great when thye came back. On at least one test it ran past the 10 minute time limit before delivering.
Net Result:
If you build apps and interfaces, try it. It’s become my go-to for ambitious coding projects. I’m still roughly 80/20 Codex versus Claude in day-to-day use, and I still prefer Sol and Astra for editing. But I’m spending far more of my tokens with Claude than I was a week ago.
State of Play:
Codex is still the better harness for me, but Anthropic is steadily gaining ground. They have a history of making their smaller models perform better than their bigger ones (Sonnet 3.7 for example) and they seem to have done the same with Opus 5.5.
Full vibe check will be on @every soon!
