Python

Instructor

Reliable structured outputs from LLMs

by 567-labs · MIT

pip install instructor

What is Instructor?

Instructor makes LLMs return validated, typed structured data using Pydantic models, with automatic retries when validation fails.

Why people choose Instructor

• Pydantic-validated, typed LLM outputs
• Automatic retries on validation errors
• Works across many providers and local models

Instructor at a glance

Open-source alternatives to Instructor

Other open-source llm / rag framework tools worth comparing:

LangChainCompose chains, tools and agentsLlamaIndexThe data framework for RAGHaystackProduction pipelines for search and RAGDSPyProgram — not prompt — language modelstxtaiAll-in-one embeddings databaseRAGFlowDeep-document-understanding RAGSemantic KernelMicrosoft's enterprise agent frameworkGraphRAGRAG that builds a knowledge graph firstLiteLLMOne API for 100+ LLM providersOutlinesGuarantee valid JSON and grammarsGuidanceInterleave control and generationLLMWareEnterprise RAG with small specialised modelsFlashRankUltra-light reranking for better RAGSentence TransformersThe standard way to make embeddingsRagasMeasure whether your RAG is any goodPromptfooUnit tests for your promptsLangfuseSee what your LLM app actually didPhoenixTrace, evaluate and debug LLM apps

Instructor head-to-head

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