Weights & Biases (CoreWeave)

W&B Weave

Toolkit for tracing, evaluating and monitoring LLM apps and agents inside Weights & Biases.

Apache-2.0PythonTypeScriptv0.53.11

What it supports

  • Evaluates multi-step agents and tool calls: supportedEvaluates multi-step agents and tool callsDocs
  • LLM as a judge scoring: supportedLLM as a judge scoringDocs
  • Tracing: supportedTracingDocs
  • ?Runs in CI: not yet verifiedRuns in CI

Install

pip install weave

Links

Official documentationgithub.com/wandb/weaveHosted option: Weights & BiasesPricing

Other eval frameworks

Inspect AIpromptfooDeepEvalPydantic EvalsHarborLangfuseOpikMLflow GenAI EvaluationArize PhoenixRagasGoogle ADK EvaluationBraintrustLangSmith EvaluationMicrosoft Foundry EvaluationsGen AI Evaluation Service

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Reviewed Oct 9, 2026.