Weights & Biases

Weights & Biases (W&B) is the leading MLOps platform for tracking, visualizing, and managing machine learning experiments. W&B provides tools for experiment tracking, dataset versioning, model evaluation, hyperparameter optimization, and collaborative AI development.

W&B has become a near-universal tool in AI research and development: most major AI labs and companies use it to track their training runs, compare model performance, and collaborate on model development. The platform's experiment tracking captures every detail of a training run — hyperparameters, metrics, system utilization, model artifacts — making AI development reproducible and systematic.

In the model-building toolchain layer, W&B is essential infrastructure for the iterative process of developing the foundation models that power AI agents — providing the observability and management layer for the model training pipeline.