Anthropic is running an unreleased AI model internally that outperforms every publicly available version of Claude. That's according to the company's Risk Report from August 2026.

The report calls the model "Model 2" and places it in the Mythos class. Anthropic says it's slightly stronger overall than Claude Mythos 5, but weaker in some areas. It doesn't show a big capability jump like the one from Opus 4.6 to Mythos. On the company's internal capability index, AECI, it sits about 1.5 points above Mythos 5. That gain is smaller than the jump from Mythos Preview to Mythos 5.

Internally, the company leans on the model heavily for coding, data generation, and research and engineering, sometimes through agents that run continuously. Claude now writes most of the code in Anthropic's production systems. Model 2 went through an internal review before deployment, but wasn't tested as thoroughly as Mythos 5. Anthropic found no new or more worrying misalignments in the process. The company rates the overall risk from misalignment as "low." There are no plans to release the model externally right now.