LangChain
LLM orchestration framework. Chains, agents, RAG, the most complete ecosystem.
Strengths
- LCEL: composable chains with pipe operator, clean architecture
- LangGraph: stateful agents with loops, far beyond simple chains
- Pre-built integrations: OpenAI, Anthropic, Pinecone, Supabase, PostgreSQL
- LangSmith: native tracing and observability to debug LLM pipelines
Limitations
- Too thick abstraction, debugging a deep bug becomes a nightmare
- Frequent breaking changes between versions, painful migration
- Overhead for simple cases, a single API call doesn't need LangChain
Best for
- Complex RAG pipelines with multi-source retrieval
- LLM agents with memory, tools and conditional decisions (LangGraph)