LangChain vs LlamaIndex (2025)
LangChain for general agent pipelines. LlamaIndex for anything document and retrieval heavy.
Both are Python-first open-source frameworks that ship fast and change faster. The real question is whether your problem is primarily an agent orchestration problem or a data ingestion and retrieval problem.
| LangChain | LlamaIndex | |
|---|---|---|
| Primary strength | Agent orchestration, chains, tool use, broad LLM integrations. | Document ingestion, chunking, indexing, RAG pipelines. |
| RAG quality | Works. Not the deepest tooling. | Best-in-class. Dozens of chunking, retrieval, and rerank strategies. |
| Agent support | LangGraph is excellent for stateful multi-agent flows. | Improving. Workflows are solid but lighter than LangGraph. |
| Learning curve | Steep. Abstractions are deep and change frequently. | Moderate. More focused surface area. |
| Observability | LangSmith is excellent for tracing and eval. | Built-in callbacks; pairs well with Arize/Phoenix. |
| Community & ecosystem | Larger. More third-party integrations. | Smaller but very active, especially in enterprise RAG. |
| Stability | Has broken APIs multiple times between major versions. | More stable surface area. |
Pick LangChain when
Use LangChain/LangGraph when: you are building multi-agent workflows, need a broad set of tool integrations, or want LangSmith for evaluation.
Pick LlamaIndex when
Use LlamaIndex when: retrieval quality and document pipeline sophistication are the core of your product.
Bottom line
Many production teams use both: LlamaIndex to build and serve the retrieval layer, LangGraph to orchestrate the agent logic on top. They are not mutually exclusive.
Need help picking — or stitching them together?
We do this for clients every week. Bring us the workflow, we'll bring the architecture.
Talk to usGlossary
- OrchestrationCoordinating the flow of tasks across agents, tools, and model calls.
- RAG (Retrieval-Augmented Generation)Look up relevant documents first, then ask the model to answer using them.
- Vector DatabaseA database optimized for storing embeddings and finding the nearest matches fast.
- Agentic WorkflowA multi-step pipeline where an agent (or several) chain tools and decisions together.