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Anthropic launches Claude 4
Hybrid reasoning models target longer coding and agent tasks.
Model labAnthropic
AnthropicRelease date22 May 2025
Anthropic launched Claude Opus 4 and Sonnet 4 as one model generation, combining immediate responses with extended thinking. The developer described improvements in coding and sustained agent work; the two models had different access tiers. Anthropic
Sources & attribution
- Organizational disclosure 22 May 2025claude 4 release announcement
Anthropic. Original developer announcement.