LangChain framework is open source and free. LangSmith (observability platform) free up to 5,000 traces/month, Developer $39/month, Plus $99/month. Enterprise custom pricing.

Free for personal use with unlimited projects. Teams $50/user/month. Enterprise custom pricing with advanced security and compliance.

Open source LangChain: data stays within your infrastructure. LangSmith cloud: review LangChain's data handling policy. Enterprise LangSmith includes data processing agreements.

Review W&B's data handling policy. Metrics and model data are logged to W&B's cloud by default. Self-hosted deployment available for full data control. Enterprise includes data processing agreements.

• ✓Most widely adopted LLM application framework with large community
• ✓Integrates with virtually every LLM provider and vector database
• ✓RAG and agent patterns well-supported with established conventions
• ✓LangGraph enables complex stateful multi-agent workflows

• ✓Industry standard for ML experiment tracking with strong community
• ✓Free for individual researchers with unlimited projects
• ✓Weave extends the platform to LLM application tracing and evaluation
• ✓Integrates with all major ML frameworks
• ✓Strong visualisation and comparison tools

• ✕Abstraction layer adds complexity for simple use cases
• ✕Learning curve for understanding chains, agents, and retrieval patterns
• ✕Framework has been criticised for unnecessary abstraction in some scenarios
• ✕LangSmith observability requires separate setup and subscription

• ✕Teams plan at $50/user/month is expensive for smaller teams
• ✕Setup requires adding W&B logging code to training scripts
• ✕Can add storage costs for large model artifacts