Agent frameworks
LlamaIndex
Data framework focused on ingestion, indexing, and retrieval pipelines feeding a model.
- Category
- Agent frameworks
- Pricing
- Open source
- Runs
- Hosted or self-hosted
- Languages
- Python, TypeScript
- Interface
- Library
- Source
- Open source
What LlamaIndex is
LlamaIndex is organised around getting data to a model: parsing documents, chunking them sensibly, building indexes, and querying them at retrieval time. Its document handling is the strongest part — the unglamorous work of turning messy PDFs and HTML into something retrievable — and it has grown agent capabilities on top.
Best for
Retrieval-heavy applications where document ingestion and indexing are the hard part.
Consider something else if
If your application is agentic first and retrieval is incidental, a general framework may fit the shape better.
LlamaIndex alternatives
The closest options in agent frameworks, on the axes that actually separate them.
| Tool | Best for | Pricing | Runs |
|---|---|---|---|
| LlamaIndexopen source | Retrieval-heavy applications where document ingestion and indexing are the hard part. | Open source | Hosted or self-hosted |
| LangChainopen source | Projects that benefit from breadth of integrations, and teams who want explicit stateful graphs via LangGraph. | Open source | Hosted or self-hosted |
| Pydantic AIopen source | Python teams already using Pydantic who want type safety and a framework small enough to hold in your head. | Open source | Self-hosted |
| Claude Agent SDKopen source | Filesystem- and shell-shaped agents where the built-in tool set is most of what you need. | Open source | Self-hosted |
| DSPyopen source | Tasks with a measurable metric and enough examples to optimise against, where hand-tuned prompts keep drifting. | Open source | Self-hosted |
| Mastraopen source | TypeScript and Node teams who want a framework designed for their stack instead of a translated one. | Open source | Hosted or self-hosted |
Choosing within agent frameworks
Language, honestly
Most of this category is Python-first. If your service is TypeScript, the shortlist is genuinely shorter, and a thin layer over the provider SDK is often better than a half-maintained port.
How much it hides
Some frameworks give you primitives you compose; others give you an agent you configure. The second is faster to a demo and harder to debug at depth. Match this to how much novel behaviour you expect to need.
Questions
What is LlamaIndex?
LlamaIndex is organised around getting data to a model: parsing documents, chunking them sensibly, building indexes, and querying them at retrieval time. Its document handling is the strongest part — the unglamorous work of turning messy PDFs and HTML into something retrievable — and it has grown agent capabilities on top. It is open source and hosted or self-hosted.
What are the alternatives to LlamaIndex?
The closest alternatives are LangChain, Pydantic AI, Claude Agent SDK, DSPy, Mastra. They sit in the same category — agent frameworks — and differ mainly on hosting model, pricing shape, and how much they abstract away.
Is LlamaIndex the right choice?
Retrieval-heavy applications where document ingestion and indexing are the hard part. The main caveat: If your application is agentic first and retrieval is incidental, a general framework may fit the shape better.
Whatever you build on, the model is the line item that scales. See what each one costs per million tokens, or price your own workload.