Instructor is completely free with 5 features included. No paid tiers offered, making it perfect for budget-conscious users.
Instructor adds Pydantic validation to catch type errors and constraint violations, automatic retry with error feedback when parsing fails, and a consistent API across 15+ providers. Raw function calling gives you JSON to parse yourself; Instructor provides validated Python objects with intelligent retry logic.
Yes. Use create_partial() for streaming partial Pydantic objects where fields populate incrementally, and create_iterable() for streaming complete objects one at a time from lists. Streaming works with all extraction modes and supported providers.
Instructor focuses on fast, schema-first extraction from single LLM calls. PydanticAI (from the Pydantic team) provides a full agent runtime with tools, observability, and production dashboards. They're complementary - use Instructor for extraction, PydanticAI for agent workflows.
Yes. Instructor has native Ollama integration for any model Ollama serves. Larger models (70B+) handle complex schemas reliably, while 7B models work well for simple 3-5 field extraction. Use JSON mode instead of TOOLS for models with limited function calling.
Instructor uses post-generation validation with retries and works with any API provider. Outlines uses constrained generation for guaranteed schema compliance but requires self-hosting. Instructor is easier for cloud APIs, Outlines better for local deployment with zero retries.
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Last verified March 2026