LangSmith vs Weights & Biases Weave

LangSmith is an LLM observability platform that provides tracing, monitoring, and evaluation for AI agents and LLM applications. It offers native tracing for agent frameworks, cost and latency tracking, online LLM-as-judge evals, custom dashboards, and alerts via webhooks or PagerDuty. Framework-agnostic with SDKs for Python, TypeScript, Go, Java, and OpenTelemetry support, it works with OpenAI, Anthropic, LlamaIndex, and custom stacks. Typical buyers are engineering teams building production LLM apps needing visibility into agent behavior, debugging failures, and performance optimization. Enterprise plans include self-hosted and BYOC options for data residency.LangSmith homepage Pricing

Weights & Biases (W&B) is a San Francisco-based MLOps and LLMOps platform founded in 2017. Weave is W&B's product layer purpose-built for LLM observability, evaluation, and governance. It provides automatic tracing of LLM calls (inputs, outputs, latency, cost), evaluation pipelines with human and automated scoring, dataset versioning, and guardrails to block prompt attacks and harmful outputs. Weave integrates with major LLM providers including OpenAI, Anthropic, Google Gemini, and frameworks such as LangChain and LlamaIndex. For AI compliance, W&B runs EU AI Act-focused webinar series demonstrating how Weave can generate compliance dossiers for high-risk AI systems, providing audit trails and evidence generation. The platform holds SOC 2 Type II certification. Enterprise tier includes SSO, RBAC, and private cloud deployment. W&B has raised $305M total and was valued at $1.25B in 2023.