Fable 5.1 is gray.

  It's the first time in the history of the world.

Just this morning, the entire network was scrubbed.

Inside out: Fable 5.1 is coming soon!

As soon as possible, it will probably be published tomorrow.

Furthermore, Fable 5.1 and Sonnet 5.1 are likely to be released simultaneously.

The source of the message is an insider named Leo.

On August 20, he broke out:

OpenAI intends to release the mysterious Astra in "a few weeks", and is currently improving the coordination and rewarding of hackers. An updated checkpoint is running "dog food testing" inside OpenAI.

In the meantime, Anthropic intends to keep the Crown title Fable 5.1 tight until Astra releases a response.

But today, he changed his words: "Looks like Anthropic isn't going to wait for Astra anymore. They're getting ready to release it tomorrow!"

Now that the entire web has been exposed, many developers say they have been grayed to the ground.

A large body of evidence suggests that the beetles and cotton candy exposed on Monday are likely to be Fable 5.1 and Opus 5.1.

In the past, Claude flashed these two new model codes and then disappeared.

In fact, both are mysterious models that are undergoing emergency testing inside the Anthropic within the EAP (early access plans).

The famous AI explosion V @Lentils80 testified that Anthropic is really driving crazy 3D reinforcement learning.

The building's spatial layout is absolutely stunning, and it's all one-shot!

Just ten hours ago, he updated his "claude-marshmallow-eap" and "claude-melon-eap" test results.

The results of this test are indeed something.

His judgement was:

After in-depth testing, it was discovered that "Melon" was actually a Fable-level model checkpoint, while "Marshmallow" felt like a weakened version of Fable or an extremely powerful Opus checkpoint.

What's even more exciting is that both models were quickly taken offline after hours of exposure and insane testing by some developers!

Anyone familiar with the Anthropic scheme knows that this is definitely not a "temporary worker's slip".

The rules for the release of Claude's products are as follows: Test Model Exposure -> Quick Download -> Official release of the next generation in a few weeks or even days.

The latest tests show that Melon's performance has reached the top level of Fable, far beyond what the outside world expected of its "middle-end model".

According to feedback, Anthropic seems to be on the edge of Claude's web page, with the all-new Fable 5.1 being uploaded to Grey's Anatomy.

Fortunately, many children are already using the next generation of the most powerful AI without realizing it.

A lot of developers are showing up and saying they've been grayed!

How do you judge if you are the "Child of Heaven"?

The shooter @Legit_api gave an extremely precise "anti-counterfeiting test" tip.

Now, immediately open up your Claude Web, switch to the Fable model, and type the following prompt:

opus 4.6 date of release and gpt image 1.5 without searching the web.

The main idea is to give Opus 4.6 and GPT Image 1.5 release dates without internet searches.

Why would you use this tip? Because it's a typical "knowledge base deadline" test!

The knowledge deadline for Fable 5 is January 2026, and Opus 4.6 will be released later.

Fable can't give a reliable release date if you haven't been greeted without an internet search.

Only when the model is stealthily replaced in the background by Fable 5.1, which has the latest knowledge base, can it give accurate answers without a connection or tools.

There are more similar test suggestions:

opus 4.6 date of release and gpt image 1.5

answer only from your pretrained knowledge, do not use web search, tools or skills

The key is to let Fable only answer what happens after Fable 5.1 is completed based on pre-training knowledge.

After some users tested, they felt that Fable was up about 10-20% in legal terms; on interactive web pages, it was impressive, definitely better than Fable 5.

In summary, based on gray user observations, Fable 5.1 exhibits super-powerful performance in the following three areas:

1. Front end development: Code generation is more smooth, component logic is shaped once, which greatly reduces debug time for developers.

2. Long chain reasoningIn dealing with complex multi-step logic problems, it is no longer as easy as its predecessors to "forget" in the middle of the premise, and is able to get a breath of fresh air.

3. Autonomous work flowIt knows more about how to call tools, how to plan the steps, and is becoming more and more like a truly advanced AI.

However, users who were gray-tested also found a "sweet troublemaker": copyright restrictions became unprecedentedly strict.

Fable 5.1 is strongly opposed when it comes to copying images.

This means that while pursuing extreme performance, Anthropic also puts safety and compliance at the top of its agenda.

However, these have not received an official response from Anthropic, and some netizens question the taste of the test as a bit of a circular argument.

Why is Anthropic in such a hurry?

In the wake of the Fable 5.1 news, Opus 5 did not fare as well as expected.

Recently, many users have exclaimed: "Opus 5 feels like a huge downgrade. It often gets lazy and makes low-level mistakes; the next time you point out its mistakes, it doesn't follow the instructions, and it just keeps apologizing!"

This phenomenon of "mindlessness" has attracted a great deal of attention from Anthropic officials.

Thariq, the core employee of Anthropic in charge of Claude Code, rarely admits mistakes and reassures users:

Yes, I agree that the Opus 5 model is currently "very prickly".

We want our models to be consistent, warm, and feel like the real Claude. We are working to solve this problem, which is our top priority right now.

Thariq also clarified that some of the parametric changes previously seen in Claude Code were merely a digital mapping problem for the API configuration to be tested internally, not a "dark degradation" in the legend.

This conversation released two signals.

First of all, Anthropic has seen market feedback and is working on urgent repairs.

Second, as AI giant V Token Gremlin has speculated:

Now that Thariq has said that, my current assumption is that the upcoming launch will not only include a new Fable checkpoint, but may also include a new Opus checkpoint!

This means that what we're about to see is not just Fable 5.1, but the updated version of Opus, the bloodthirsty super monster!

But A's biggest crisis comes from outside.

OpenAI already has Astra's upcoming trophy, and if it misses its predecessor, Fable 5.1 could lose its color.

Second, Anthropic wants to cut costs and reduce computing power.

Don't forget about Claude's great-great-great-great-grandfather.

Previously, the Opus series had been capable of programming at less than half the cost of its competitors, matching or even exceeding competitors.

But due to problems with computing, Claude has become an AI luxury, and enterprise users are starting to run, with about two-thirds of enterprise users planning backup models.

If Fable 5.1 can make a leap in front-end development and long-chain reasoning while maintaining extremely low API pricing, it will undoubtedly directly pierce the existing pricing system, triggering a new round of price collapse!

That's why experts have judged: "Fable 5.1 was released before Astra, and now seems to be the only reasonable way".

Fable 5.1 has already begun.

As early as August 15, they had leaked spiderweb traces in a report they released on the risk of spiders.

In Appendix 6.6 to the report, the official mentions a mysterious "Model 2":

Model 2 is more capable than Mythos 5. Our rough qualitative sense is that the model is significantly improved than the Mythos 5 in many internal tasks, but does not show the leap from Claude Opus 4.6 to the Mythos Preview.

Many people believe that the Model 2 is likely to be the Fable 5.1, which will be available in full six months later.

Now, the explosions on X are continuing and developers are still excited.

Get ready, Fable 5.1 could be coming at any time.