Anthropic tests its next model under Claude Opus 5.5

Anthropic appears to be quietly testing another model in the wild. Over the weekend, several users on X noticed Claude Opus 5.5 producing results well beyond its usual level, suggesting some of that traffic is being routed to a new checkpoint. Interestingly, this comes just three weeks after Anthropic launched Opus 5.5 with lower API costs. X user can was among the first to spotlight the potential new model in testing. They shared a recording of the output they got from a single-sentence prompt that had the model use Blender's MCP.

Also reported by TestingCatalog AI News.

First reported by TestingCatalog. This page is a short excerpt; the full text is theirs.