Claude Sonnet 4.5 (2025-09-29)

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anthropic llm
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A dated snapshot of Anthropic's Claude Sonnet 4.5 model for consistent API behavior.

context window 200K tokens
max output 64K tokens
input price $3 / 1M tokens
output price $15 / 1M tokens
tool-usejson-modestreamingreasoningcode-generationfunction-callingprompt-cachingvision
releasedSep 2025