May 22, 2025
Anthropic Claude 4 Opus and Sonnet released
AnthropicAn AI safety company — creators of the Claude family of language models. released Claude Opus 4 and Sonnet 4 on May 22, 2025 — hybrid reasoningStep-by-step logical thinking in AI models — chain-of-thought before answering hard problems. models with extended thinking, parallel tool use, and state-of-the-art coding scores.
What it was for
Claude 4 made extended thinking with tool use a default capability and shipped Claude Code to general availability. Opus 4 led SWE-bench and long-running agent tasks; Sonnet 4 balanced cost and capability for everyday coding — intensifying the three-way race with OpenAIAn AI research company — created GPT, ChatGPT, DALL-E, and the o-series reasoning models. o3 and GeminiGoogle's family of multimodal AI models — successors to PaLM and competitors to GPT and Claude. 2.5.
Companies
- Anthropic
Why it's here
Claude 4 paired frontier coding with production-ready agent tooling.
Why it mattered
Parallel tools and memory files pushed agenticAI systems that plan and execute multi-step tasks autonomously — tools, browsing, and sub-agents. coding from demo to daily workflow.
What it solved
Developers needed models that could sustain multi-hour coding and research sessions reliably.
Media
- ImageAnthropic
Anthropic, Public domain, via Wikimedia Commons
Related
- Anthropic Claude 3.7 Sonnet releasedFebruary 24, 2025
- OpenAI o3 and o4-mini releasedApril 16, 2025
- Google Gemini 2.5 Pro releasedMarch 25, 2025
- Anthropic Claude Opus 4.5 releasedNovember 24, 2025