Claude Sonnet 5.5 arrives in Claude Code
Anthropic releases Claude Sonnet 5.5 across its platforms and explicitly positions it for faster agentic coding in Claude Code.
Anthropic releases Claude Sonnet 5.5 across its platforms and explicitly positions it for faster agentic coding in Claude Code.
Claude Code was documented with earlier Claude models and existing effort and agent features.
Claude Sonnet 5.5 is available as a current model option and is explicitly positioned by Anthropic for fast agentic coding work.
Anthropic released Claude Sonnet 5.5 on September 28, 2026. The provider describes it as a faster and more efficient update to Sonnet 5, with more than 30 percent faster output generation and lower token use for many tasks. The model is available across Anthropic platforms and major cloud partners.
Claude Code is directly relevant because Anthropic discusses the new model in the coding context. In Claude Code and the Claude apps, the default effort level is described as Medium. Lower effort can favor speed and token efficiency, while higher effort allows more deliberation.
Anthropic also reports stronger agentic coding evaluations and more efficient tool use. AgentenCode records those numbers as provider-reported performance claims, not as an independent benchmark or overall quality score.
The model update does not automatically change Claude Code permissions. File-system, terminal and tool access remain properties of the actual Claude Code configuration and should be evaluated independently from model performance.
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AgentenCode publishes product changes only after source-first review. The original provider source remains authoritative for current details.
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