By Ruan Martini, Daily Checkpoint
On November 1, the two AI labs I write about most managed to leak their next flagship model names on the exact same weekend. OpenAI on one side, Anthropic on the other, and neither company has confirmed a single word of it. So let me plant the flag right at the top: everything below is rumor or a reported sighting, labeled as such, with the source named every time. No specs are confirmed. No prices are confirmed. No dates are confirmed. What we have are two names, a handful of screenshots, one string of text that vanished from a web page, and a small mountain of people online pretending that adds up to a launch announcement. It does not. But the names are interesting, the evidence is not nothing, and if either leak turns out to be real, it changes the AI race I keep score of on this site. So here is the weekend, sorted into what is proven, what is plausible, and what you should flat out ignore.
The OpenAI side: a label Codex was not supposed to show
The OpenAI leak is RUMORED, and the evidence is screenshots. Users of Codex, OpenAI’s coding tool, posted screenshots of their usage breakdowns where one model identifier reads gpt-6.2-astra. In one account, that label supposedly handled 19.8 percent of the usage in the October 26 to November 1 window, which is a weird detail to invent. Stranger still, the visible model picker in the same product still said GPT-6 Astra, the current name. A separate short JSON fragment carrying the same identifier circulated from a second account, so this was not one person with a photo editor and a dream.
Now the cold water. Kingy AI went looking for GPT-6.2 Astra in OpenAI’s public model catalog, the API changelog and the Codex model guides on November 1, and found no listing anywhere. Zero. And the screenshots themselves carry no request ID, no endpoint and no timestamp, which means they prove that a label was seen on a screen, not what model actually ran behind it. Labels get tested, labels get misconfigured, labels get faked. VanData Team scored this one on November 2 as thin but plausible, and that is exactly the right shelf for it. A GPT-6.2 point release would make sense as a product move. Sense is not evidence, and right now evidence is all we are grading.
The Anthropic side: a name in the page code, gone within hours
The Anthropic leak is REPORTED as a sighting, and it is the stranger of the two. On November 1 at 15:23 UTC, the X account @kimmonismus posted a screenshot of the source code of Anthropic’s official Mythos page, and sitting in that code, in a hidden heading and in a logo alt text, was the name Claude Mythos 5.5. TestingCatalog quoted the matching tagline from the page: “Our most capable model class for cybersecurity and biology research.” This was not a random fan wiki or a retailer listing. This was text inside the code of Anthropic’s own page, which is why people sat up.
Then it vanished. FourWeekMBA fetched the same page at 17:31 UTC the same day and found the 5.5 string already gone, with the page reading Claude Mythos 5.1 again. A follow-up check on November 2 found no trace of 5.5 on the live page at all. Anthropic has announced nothing. So the honest summary is narrow: for some window of time on November 1, the words Claude Mythos 5.5 existed inside Anthropic’s own page code, somebody screenshotted them, and then they did not exist anymore. That could be launch preparation that went live too early. It could be a placeholder a web developer typed and a reviewer caught. It cannot be called a product, because Anthropic has not called it one.
The Fable 5.5 numbers going around: ignore them
This is the part where I save you from the charts. Some of the posts riding this leak claim that a public model called Fable 5.5 is coming with a one million token context window and specific pricing. Those numbers are junk, and there is a receipt for why. VanData Team traced them on November 2 to a LiteLLM price file entry from October 13 that simply copied the specs and pricing of Fable 5.1, the current model, under the 5.5 name. The entry was removed on October 14, because Azure does not list any such model. So if you see a tidy Fable 5.5 price table this week, you are looking at a photocopy of the current model’s numbers wearing a new name tag. Do not budget with it, do not argue from it, do not send it to me as proof of anything. Ignore those numbers until Anthropic publishes real ones, if it ever does.
What it would mean if any of this is real
Why care about two names and no products? Because of what the names point at. Mythos is not the normal Claude line. Per the tagline TestingCatalog quoted, it is Anthropic’s restricted model class for cybersecurity and biology research, the kind of thing aimed at verified specialists rather than the general public. A 5.5 appearing there hints that a new generation is being prepared behind the curtain, and generations in the restricted line tend to have relatives in the public one. Hint is the whole claim, and I am keeping it that size.
On the OpenAI side, a GPT-6.2 point release would date every comparison on the internet, including mine. In my ChatGPT vs Claude vs Gemini comparison, I scored the current GPT-6 and Claude 5 lines against each other at twenty dollars a month, and I warned readers to treat the whole thing as a snapshot, not a stone tablet. Leaks like these are precisely why. If either lab ships a point release in November, half the verdicts in that article need retesting the week it lands. That is not a crisis, it is just the speed of this industry, but it is worth knowing before you pick a subscription based on any review, mine included.
My take
My favorite detail in this whole story is that the strongest evidence either lab leaked anything is a screenshot of a usage label and a line of page code that survived for a few hours. Billion dollar product launches, folks, announced the modern way: accidentally, in the plumbing. I am not mocking the people who caught these. Catching them is good work, and TestingCatalog and Kingy AI both did the unglamorous part, checking the official catalogs and the live page and reporting what was not there. I am mocking the second wave, the accounts that took two unconfirmed names and returned with full spec sheets and price tables, half of which turned out to be copied from a price file for the current model. The rumor mill is not broken. It is just faster than its own fact checking, by about a day, every single time.
If you forced me to bet, the Mythos sighting feels like the more substantial of the two, because the string lived in Anthropic’s own code and then somebody bothered to remove it. The Codex label could be a test name that never ships. Both could be nothing by Friday. That is what rumor means, and anyone who tells you more than that today is selling you something.
What happens next
Simple watch list. On the OpenAI side, the model catalog and the API changelog are where a real GPT-6.2 Astra would have to appear, and Kingy AI is already watching both. On the Anthropic side, an official announcement is the only thing that turns Mythos 5.5 from a screenshot into a model. The moment either company posts something official, I will update this piece and the comparison article with the confirmed specs and pricing, and the rumor labels come off. Until then, the labels stay exactly where they are, and so does my subscription money.
Sources
- TestingCatalog, November 1, 2026: Claude Mythos 5.5 reference on Anthropic’s official Mythos page, with the tagline text, later removed.
- Kingy AI, November 1, 2026: GPT-6.2 Astra tracker, cataloguing the Codex usage screenshots and confirming no GPT-6.2 Astra entry exists in OpenAI’s public docs, catalog or changelog.
- VanData Team, November 2, 2026: evidence scoring of both leaks, including the debunk of the copied Fable 5.5 pricing and context figures.
- FourWeekMBA, November 1, 2026: independent fetch of the Anthropic Mythos page at 17:31 UTC showing the 5.5 string already removed.
Leave a Reply