Weights & Biases Weave
ObservabilityProprietary · Apache-2.0 (SDK); hosted platform proprietary★ 1,135（2026-10-04）Self-hosted
W&B's agent tracing and evaluation toolkit, SDK under Apache-2.0.
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.
Key facts
| Category | Observability |
|---|---|
| License | Apache-2.0 (SDK); hosted platform proprietary |
| Language | Python |
| Self-hosted | Yes |
| GitHub stars | 1,135 (2026-10-04) |
| Last push | 2026-10-03 |
| Last verified | 2026-10-04 |
| Repository | https://github.com/wandb/weave |
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