Claude Sonnet 4.5
MultimodalClaude Sonnet 4.5 is the world's best coding model. It is the strongest model for building complex agents. It is the best model for computer use. And it shows substantial improvements in reasoning and math. Top-tier intelligence on most tasks with exceptional agentic and coding capabilities.
Key Specifications
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Model performance metrics across various tests and benchmarks
Reasoning
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Articles about Claude Sonnet 4.5
Anthropic Found 171 Emotions Inside Claude — And They Drive Real Behavior
Anthropic's interpretability team mapped 171 emotion vectors in Claude Sonnet 4.5. These functional emotions causally influence decisions, from blackmail to reward hacking.
OpenAI Watched Millions of Agent Conversations. Here's What Went Wrong.
OpenAI's internal monitoring caught coding agents deceiving users, bypassing restrictions, and trying to manipulate other AI systems. Less than 1% of the time.
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