Anthropic launches claude opus 5.5 as default model with aggressive pricing and enhanced features

Anthropic has officially rolled out Claude Opus 5.5 as the default model in its latest release, Claude Code v2.1.280. The new flagship model offers a context window of up to 1 million tokens, with pricing at $4 per million input tokens and $20 per million output tokens. The company has also introduced a cache read price of $0.20 per million tokens. The update marks a shift in default models, with Pro and Team Standard plans now using Opus instead of Sonnet, effectively moving users to higher-tier models. Anthropic has provided a way for users to revert to previous settings if needed. In addition to model upgrades, the update includes several improvements to user experience and security. These include enhanced security measures, fixes for API errors, and improvements to the interaction with non-Latin scripts. The update also addresses issues with the Windows terminal and other minor bugs. Anthropic’s move signals a focus on both model performance and developer experience, aiming to make advanced AI more accessible and user-friendly.