Skip to main content

Agent frameworks for developers: pick a stack

Guide · 2026-09-11 · 1 min read

Compare LangChain, LlamaIndex, CrewAI, AutoGen, and related agent frameworks—when to use each, and how they fit RAG and tooling.

  • agents
  • frameworks
  • rag
  • developers

Agent frameworks for developers: pick a stack

Building an agent is easy to demo and hard to operate. This guide maps the frameworks db.fyi tracks so you can pick a stack without reading every README.

Start here

| Need | Start with | Hub | |------|------------|-----| | General orchestration + tools | LangChain | Agent frameworks | | Document / RAG-heavy apps | LlamaIndex | RAG tools | | Multi-agent crews | CrewAI or AutoGen | Best AI agents | | Visual / low-code flows | Dify, Flowise, n8n | | | Observability | Langfuse, LangSmith | AI for agent observability |

Decision rules

  1. If retrieval quality is the product, prefer LlamaIndex or Haystack and invest in chunking, embeddings, and evals (AI for RAG, AI for LLM evaluation).
  2. If tool calling and graphs dominate, LangChain / LangGraph-style stacks or Semantic Kernel fit better.
  3. If you need many specialized agents, CrewAI or AutoGen; keep a single shared memory and eval harness.
  4. If non-engineers own the workflow, Dify / Flowise / n8n beat a custom Python service for the first version.

Compare pages

What we will not claim

No framework is “best” in the abstract. Prefer evidence: your latency budget, who maintains the graph, and whether you can evaluate regressions (promptfoo, RAGAS).