Bloom: an open source tool for automated behavioral evaluations

We are releasing Bloom, an agentic framework for developing behavioral evaluations. Bloom's evaluations are reproducible and targeted: unlike open-ended auditing, Bloom takes a researcher-specified behavior and quantifies its frequency and severity across automatically generated scenarios. Bloom's evaluations correlate strongly with our hand-labelled judgments and reliably separate baseline models from intentionally misaligned ones. As examples, we also release benchmark results for four alignment relevant behaviors on 16 models. Bloom is available at github.com/safety-research/bloom.