Introducing Bloom: an open source tool for automated behavioral evaluations \ Anthropic

Anthropic is an AI safety and research company that's working to build reliable, interpretable, and steerable AI systems.

Alignment Introducing Bloom: an open source tool for automated behavioral evaluations Dec 19, 2025 Read the technical report We're releasing Bloom, an open source agentic framework for generating behavioral evaluations of frontier AI models. Bloom takes a researcher-specified behavior and quantifies its frequency and severity across automatically generated scenarios. Bloom's evaluations correlate strongly with our hand-labeled judgments and we find they reliably separate baseline models from intentionally misaligned ones. As examples of this, we release benchmark results for four alignment rel

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