Amodei said her organisation had developed a powerful new class of model and, in a decision she linked to Project Glasswing, held off wide release because it felt it needed more time to ensure the model was safe.

Judged as of 2026-05-09. True: Anthropic's official announcements show that by that date it had developed a model it presented as a new, more capable class, and had held back or restricted its wide or general release on safety grounds, with the decision linked to Project Glasswing (for example, limited access given to partners under Glasswing instead of general availability). Mostly true: the model and the safety-based hold-back are documented, but a detail is off, such as the exact framing of the model as a 'new class', or how closely it is tied to Glasswing. Mixed: a model was withheld or limited, but mainly for reasons other than safety (e.g. compute or commercial reasons), or there is no link to Glasswing. Mostly false: the model was in fact widely released at the time, with only minor staging, or the withholding was about a minor safety issue that has been overstated. False: no such model was withheld, or Project Glasswing has nothing to do with any model release decision.

Set before the research began.

1. E1 Project Glasswing Anthropic · 7 April 2026 Own record

   “Claude Mythos Preview is a general-purpose frontier model from Anthropic, our most capable yet for coding and agentic tasks.”

2. E2 Project Glasswing Anthropic · 7 April 2026 Own record

   “Mythos Preview has already identified thousands of zero-day vulnerabilities across critical infrastructure, and is available today as a gated research preview.”

3. E3 Expanding Project Glasswing Anthropic · 2 June 2026 Own record

   “We’re working as quickly as we can to safely release Mythos-level capabilities in general access. To do so, we’ll need highly robust safeguards that prevent the model’s cyber capabilities from being misused”

4. E4 Daniela Amodei Says Curiosity Is Underrated Stanford Graduate School of Business · 29 June 2026 Own record

   “That sometimes means that we take slightly unusual actions, like we did with Project Glasswing and say, “This new class of model, it would be great if we could just release this to all of our customers. They all would love to use it,” but we’re just not confident enough yet.”

Anthropic's Project Glasswing page (E1, E2), dated 2026-04-07, presents Claude Mythos Preview as its most capable model yet and says it is available only as a gated research preview tied to Glasswing, not as a general release. A later Anthropic post (E3) links general access to building robust safeguards against misuse of the model's cyber capabilities, which supports safety as the reason for the hold-back. The official records describe the model as 'most capable yet' rather than a 'new class'; that wording comes from Amodei's own remarks (E4), so the framing detail is not fully matched.