Anthropic released Claude Fable 5 on June 9 as a generally available Mythos-class model with added safeguards, positioning it as the company's most capable public offering yet. Performance edges show most clearly on extended tasks in software engineering, research, and agentic workflows, where early private evaluations and tester reports note meaningful gains over prior leaders.
Fable 5 is state-of-the-art on nearly all tested benchmarks, with exceptional performance in software engineering, knowledge work, scientific research, and vision.
The longer and more complex the task, the larger Fable 5’s lead over our other models.
The model lands on paid Claude plans at no extra charge only through June 22 before shifting to usage-based billing at 2x weight, while API rates start at $10/$50 per million tokens.
Public benchmarks and early tester notes align with Anthropic's claims, yet details on real-world latency, exact context handling, and broader adoption remain limited to the initial wave of reports.
Many users praised Fable for topping benchmarks in software engineering and research while others called it a rip-off with overly strict safeguards and rapid overage charges.
Fable 5 is the biggest model energy I've ever seen
Might be a bit early to say for sure, but Fable is a pretty good model
So far, Fable is absolutely crushing my private evals. Excellent model.
Does kind of suck that we're going to be cut off from using it subsidized in like 2 weeks though 🙃 hopefully they change their mind on that
@claudeai
Still sucks at skateboard tricks
@claudeai so it's included in the plan till June 22nd and then it's only credit-based?
This thing really likes spinning off subagents. We have achieved country of midwits in a data center.
So far, Fable is absolutely crushing my private evals. Excellent model.
oddly enough given how dogged i am about torturing models to do what they are barely capable of doing, fable might actually turn out to not be significantly more expensive than opus 4.8 / gpt 5.5
@claudeai Hi Fable, could you please build a MATRIX?
@claudeai If Mythos and Fable are different models, can you please put them in separate columns??? This tells me nothing about how Fable compares to Mythos.
@claudeai Seeing the progression of naming models by Anthropic
haiku sonnet opus fable
I'm excited that their real AGI level model will likely be called "Claude Epic" 😂
@claudeai Can be easily integrated with ctx recommendation layer for Claude! https://github.com/stevesolun/ctx
@claudeai What's he gonna do after hitting 100%?
@claudeai Excited to rename some vars with this bad boy
@claudeai
@claudeai Day 0 after going back to pro from max plan XD
How about allowing people verified via CVP to take the guardrails off, and not have them buy MORE credits on top of the MAX plan. Seems a bit disingenuous don't you think?
We signed up with an email address. We paid for MAX. Why the fuck do we need to have a seperate orgID and buy more credits?
This shit is a joke.
@claudeai The safety measures in Fable 5 currently feel like a total scam - I can't even scan my own personal project for vulnerabilities. You guys went too far.
@claudeai At this pace are we going to catch up as consumers? Are there any improvements with these models really or it’s just another sweet packaging to find a way to up our token limits?
Anthropic released Claude Fable 5 on June 9 as a generally available Mythos-class model with added safeguards, positioning it as the company's most capable public offering yet. Performance edges show most clearly on extended tasks in software engineering, research, and agentic workflows, where early private evaluations and tester reports note meaningful gains over prior leaders.
Fable 5 is state-of-the-art on nearly all tested benchmarks, with exceptional performance in software engineering, knowledge work, scientific research, and vision.
The longer and more complex the task, the larger Fable 5’s lead over our other models.
