LlamaIndex vs Microsoft Agent Framework
Both are free/open-source alternatives to LangChain. Here's how they stack up — verified facts, no spin.
LlamaIndex
The focused RAG framework — data in, grounded answers out.
LlamaIndex (MIT, ~49k stars) is the framework to pick when your problem is specifically retrieval — getting your documents ingested, indexed, and answered over. Its primitives are built around the data side (loaders, indexes, retrievers, query engines) rather than trying to abstract everything, which keeps it noticeably leaner to reason about than LangChain for RAG builds. The company monetizes hosted parsing/extraction (LlamaCloud); the framework itself stays open and self-sufficient.
Microsoft Agent Framework
Semantic Kernel + AutoGen, unified — the enterprise agent stack.
Microsoft's Agent Framework 1.0 (April 2026) merged Semantic Kernel's enterprise foundations with AutoGen's multi-agent orchestration into one MIT-licensed SDK for .NET and Python — session state, type safety, middleware, telemetry, and graph-based workflows out of the box. It's the natural LangChain alternative for enterprise teams (especially .NET shops and Azure environments) that want long-term-supported APIs and a vendor standing behind the framework.
Side by side
| LlamaIndex | Microsoft Agent Framework | |
|---|---|---|
| Sovereignty Score | 90 | 80 |
| Open source | Yes | Yes |
| Self-hostable | Yes | Yes |
| Local-first | Yes | No |
| License | MIT | MIT |
| Pricing | Free (MIT); optional hosted LlamaCloud for managed parsing/extraction | Free (MIT); integrates naturally (but not exclusively) with Azure services |
LlamaIndex edges it on the Sovereignty Score, but the right pick depends on the trade-offs below.
LlamaIndex
Strengths
- +Purpose-built for RAG — the data primitives are the product
- +Leaner mental model than LangChain for retrieval apps
- +Huge loader/integration ecosystem for document types
Trade-offs
- −Less suited to general agent orchestration than dedicated tools
- −Fast-moving API surface — pin versions
Microsoft Agent Framework
Strengths
- +Enterprise plumbing included: sessions, telemetry, middleware
- +First-class .NET as well as Python
- +Stable 1.0 APIs with Microsoft LTS backing
Trade-offs
- −Microsoft-governed direction; strong Azure gravity
- −Heavier than needed for small apps
More LangChain head-to-heads
Facts verified 2026-07-16. Licenses and pricing change — spotted something out of date? That's a correction we want.