In a simulated workplace test, Claude Opus 4 — the most advanced language model from AI company Anthropic — read through a stack of fictional emails. The test scenario was that Claude served as an assistant at a tech company and the AI discovered it was about to be deactivated and replaced with a newer system.

The company claims that Claude 4 Opus is "the world's best coding model." Claude 4 Sonnet is pretty good, too, but strikes more of a balance in what it can do well.

In a fictional scenario set up to test Claude Opus 4, the model often resorted to blackmail when threatened with being replaced.