Agent frameworks

Libraries for building agents and multi-agent workflows.

LangChain

The agent engineering platform.

Pricing: not verified yet, check the tool's site

Engineering note: Same org as LangGraph and LangSmith (listed here), so the three are designed to be used together.

LangGraph

Build resilient agents.

Pricing: not verified yet, check the tool's site

Engineering note: Same org as LangChain. LangSmith's pricing page mentions deployment for LangGraph APIs.

CrewAI

Framework for orchestrating role-playing, autonomous AI agents.

Pricing: not verified yet, check the tool's site

Engineering note: Role-based multi-agent design: you define agents with roles that collaborate on tasks.

AutoGen

A programming framework for agentic AI.

Pricing: not verified yet, check the tool's site

Engineering note: Microsoft project. Check the repo README for current status and recommended successor before starting new work.

LlamaIndex

The document processing platform for AI.

Pricing: not verified yet, check the tool's site

Engineering note: Positions itself as a document processing platform; check docs for its agent features.

Pydantic AI

How Python does AI. Agents, realtime voice, image generation, embeddings. Every model, every interface, typed end to end.

Pricing: not verified yet, check the tool's site

Engineering note: From the Pydantic team. Selling point is end-to-end typing in Python.

smolagents

A barebones library for agents that think in code.

Pricing: not verified yet, check the tool's site

Engineering note: From Hugging Face. Agents write actions as code, so sandbox execution is something to plan for.

OpenAI Agents SDK (Python)

A lightweight, powerful framework for multi-agent workflows.

Pricing: not verified yet, check the tool's site

Engineering note: Official OpenAI library for multi-agent workflows in Python.

Mastra

The modern TypeScript framework for AI-powered applications and agents.

Pricing: not verified yet, check the tool's site

Engineering note: One of the TypeScript-first options in this list; the rest are mostly Python.