AI Frameworks
LlamaIndex
LLM data framework for connecting custom data sources to language models. Best-in-class RAG, data connectors, and query engines. Python and TypeScript.
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LlamaIndex is the go-to framework for connecting your own data to large language models. It provides data connectors (LlamaHub) for ingesting from PDFs, databases, APIs, Notion, Slack, and hundreds of other sources. The indexing layer chunks, embeds, and stores your data in any vector database. Query engines handle retrieval-augmented generation with support for recursive retrieval, sub-question decomposition, and multi-document synthesis. It also includes an agent framework with tool use and multi-step reasoning. Available in both Python and TypeScript (LlamaIndex.TS). If your use case is primarily about making LLMs smarter with your own data rather than building autonomous agents, LlamaIndex is more focused and mature than LangChain for that specific problem.
LlamaIndex at a glance
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- Pricing
- LlamaIndex framework - free and open source (MIT)
- LlamaParse Free - 10K credits included
- LlamaParse Starter - 40K credits included, pay-as-you-go up to $500/mo
- LlamaParse Pro - 400K credits included, pay-as-you-go up to $5,000/mo
- LlamaParse Enterprise - contact sales; credits are 1,000 for $1.25
- Install
pip install llama-indexpip install llama-index-core llama-index-readers-file llama-index-llms-ollama llama-index-embeddings-huggingface- Models
- Out of the box it uses OpenAI gpt-3.5-turbo for generation and text-embedding-ada-002 for embeddings, and the docs recommend passing text-embedding-3-small for new projects. To use another provider, such as Ollama for the LLM or Hugging Face embeddings, install its integration package and pass the model in.
- Recent changes
- v0.14.25 adds native async support to StructuredLLMRerank, stops retrying failed function tools, removes the deprecated ipex-llm and optimum-intel IPEX integrations, and resolves security alerts across integration packages.
- v0.14.24 adds Claude Sonnet 5 and Claude Opus 5 to the Anthropic and Bedrock Converse integrations, GPT-5.6 to the OpenAI integration, and lets Memory accept any AsyncDBChatStore.
Sources: run-llama/llama_index README, llama_index LICENSE, llama_index releases, LlamaIndex installation and setup, LlamaIndex pricing
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Get started with LlamaIndex
LLM data framework for connecting custom data sources to language models. Best-in-class RAG, data connectors, and query engines. Python and TypeScript.
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