DSPy

Stanford’s framework for programming — not prompting — language models, with automatic prompt optimization

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Haystack

Open-source framework for building production-grade retrieval-augmented generation and search pipelines

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Microsoft AutoGen

Framework for building multi-agent AI systems where LLM agents collaborate, debate, and use tools to solve complex tasks — from Microsoft Research

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CrewAI

Python framework for orchestrating role-based multi-agent teams that collaborate to complete complex tasks

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Hugging Face

The hub for open-source machine learning models, datasets, and spaces — essential for working with transformers and LLMs in Python

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Instructor

Structured outputs from LLMs using Pydantic — extracts typed, validated data from any LLM response, eliminating JSON parsing headaches in AI pipelines

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LangChain

The most widely used Python framework for building LLM-powered applications, with 700+ integrations and tools for agents, RAG, and chains

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LangGraph

Framework for building stateful, multi-step AI agent workflows as graphs — ideal for complex reasoning and tool-use pipelines

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LlamaIndex

Data framework for building LLM-powered applications over your own data — handles ingestion, indexing, retrieval, and query pipelines for RAG systems

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Ollama

Run large language models locally with a simple Python API — supports Llama, Mistral, Gemma, and dozens more open-source models

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OpenAI Python SDK

Official Python client for the OpenAI API — supports chat completions, embeddings, assistants, streaming, and function calling with full async support

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Pydantic AI

Type-safe Python framework for building production AI agents, built by the Pydantic team with structured outputs and dependency injection

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smolagents

Hugging Face’s lightweight agent library — minimal, readable code for building tool-using LLM agents with support for any model via the Transformers ecosystem

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