# Weights & Biases Weave

> Weave is Weights & Biases' Apache-2.0 toolkit for tracing and evaluating AI agents, offering guardrails, a playground and leaderboards; W&B itself has been acquired by CoreWeave, and a self-hosted W&B Server is published separately.

W&B's agent tracing and evaluation toolkit, SDK under Apache-2.0.

- **Category:** Observability
- **License:** Apache-2.0 (SDK); hosted platform proprietary
- **Language:** Python
- **Self-hosted:** Yes
- **GitHub stars:** 1135 (2026-10-04)
- **Repository:** https://github.com/wandb/weave
- **Last verified:** 2026-10-04

Source: https://agent.c8.fit/tools/wandb-weave/