Claude Sonnet 5.5 and Opus 5.5 Land in AWS GovCloud
Anthropic just dropped two fresh models in Kiro for AWS GovCloud (US): Claude Opus 5.5 crushes long-running agentic tasks with 40% fewer tool calls, while Claude Sonnet 5.5 delivers 30% faster output without sacrificing real-world coding chops. Both pack 1M context windows and are ready to roll once you update your IDE or CLI.
source: [aws/whats-new]