Signs of two new models of OpenAI and Anthropic appear in Codex statistics, website source code and cloud catalogs, but no company has spoken out yet.

Over the weekend, the AI ​​community was abuzz with signs of two unannounced models: OpenAI's GPT-6.2 Astra, along with Anthropic's Claude Fable 5.5 and Mythos 5.5. No company has confirmed yet. Evidence includes several demos, an entry in the pricing catalog, and a label hidden in the site's code, the latter two of which were removed shortly after appearing.

On OpenAI's side, some accounts saw the line gpt-6.2-astra in the usage statistics page of Codex, the company's programming assistant tool, even though the model selector still said GPT-6 Astra. A snapshot circulating on social network Many people saw this item, so the community guessed that OpenAI was A/B testing, meaning giving the new version to a portion of users without changing the display name. Rates vary between accounts. OpenAI launched GPT-6 Astra on September 3 and has not announced version 6.2.

The Anthropic side has two traces. On the night of November 1, the Chubby account, an AI watcher with many followers, posted a photo of the Mythos page source code on its website, including the label "Mythos 5.5". According to this person, the photo came from an anonymous email. The label appears six times in the hidden code, in the hidden title and the logo's alternate description, while the visible content still says version 5.1. When I checked the running page on November 2, I only saw 5.1.

The second trail lies in LiteLLM, an open source tool that helps programmers connect multiple AI vendors. On October 13, an automatic update added "claude-fable-5-5" after the Azure cloud catalog listed the model. That entry copied the full price and limitations of Fable 5.1, noted that no source mentioned the price or capabilities of version 5.5, and was removed the next day because Azure didn't actually list it. Some posts say the MLflow directory still has this item, but it hasn't been verified.

Since early October, users claim that some requests sent to Claude Opus 5.5 are "routed" to an unannounced more powerful model, which they call Fable 5.5. Shared products include 2D animations that draw each frame using JavaScript code. According to a summary article, someone said a 66-second movie, from images, music, sound to subtitles, was written by the model in Python and packaged in an HTML file, running continuously for about 2 hours and 40 minutes. These demos are mainly photos and videos posted by users, which have not been independently verified. One person sharing even posed it as a question, not an assertion.

In the meantime, a repository on Hugging Face named burner22/numbat spread on X with the introduction of being a checkpoint in the middle of the training process of the next batch of Mythos. This repository was created on October 23, recording about 14 trillion parameters, with a capacity of 7.72 TB divided into 772 files. By the evening of November 1 (UTC time), the warehouse had 5,846 downloads.

After just a few hours, the community pointed out that this was a fake. Many independent testers found the tensors in the repository could be accurately recreated from their names, meaning they were random numbers and not trained weights. A Hugging Face engineer said the download was not malicious but warned of risks from fake repositories. The repository requires users to run an included Python script when loading the model, a step that should be taken with caution. Anthropic has not commented on this warehouse as of the evening of November 1.

Regarding timing, Anthropic filed for IPO on October 26. According to regulations of the US securities regulator, records must be made public 15 days before the presentation trip to investors, so the earliest it can start is November 10. The community is not unanimous: some people guess the model will come out this week, others think it won't be until mid-November, as a "gift" for the listing.

The recent release pace has been quite heavy. Fable 5 launches on June 9, Fable 5.1 on September 1 and Opus 5.5 on September 22. On the OpenAI side, GPT-6 Astra was released on September 3.

At the time of writing, Anthropic's Mythos page only shows version 5.1, OpenAI has not announced version 6.2, and there is no official information on price, context restrictions or launch date.