Anthropic's Claude Mythos 5.5 name surfaces in website HTML
The name appears six times on Anthropic's Mythos introduction page, while the public site still lists Mythos 5.1. No release details have been disclosed.
The model name Claude Mythos 5.5 has been found six times in the HTML code of Anthropic's Mythos introduction page, according to aitimes.com. The company's public-facing page still shows the existing Mythos 5.1, and Anthropic has not officially announced release plans for a new model.
The page's October 23 record did not contain the phrase, suggesting the name was added recently. No performance details or release schedule for the new model have been disclosed.
Separately, posts also point to testing of Claude Fable 5.5, the general-user model. Anthropic has not officially announced release plans for either model.
OpenAI reports remain unverified
Some developers claim they found the name GPT-6.2 Astra in usage records tied to OpenAI's Codex coding tool. X user Fini.Yang said he was included in limited testing of GPT-6.2 Astra, and another developer claimed the model could be run in the Codex CLI. OpenAI has not officially announced GPT-6.2 Astra.
The reports are unverified and do not confirm the models exist or are being prepared for launch.
Quick answers
Has Anthropic announced Claude Mythos 5.5?
No. The name was found in website HTML, but Anthropic has not officially announced release plans.
Is GPT-6.2 Astra confirmed by OpenAI?
No. Developers reported seeing the name in Codex records, but OpenAI has not officially announced the model and the reports are unverified.