Best frameworks for building AI agents

Code-first frameworks for agents that use tools and take actions. Updated 2026-10-15.

#1 OpenAI Agents SDK

Lightweight SDK for agents with tools, handoffs, guardrails and tracing.

Agent framework · Pricing: Open source; pay for model usage

Pros: Minimal abstractions · Built-in tracing

Cons: Best with OpenAI models

Framework for stateful, controllable multi-step agents from LangChain.

Agent framework · Pricing: Open source; hosted platform (see site)

Pros: Fine-grained control flow · Persistence and human-in-the-loop

Cons: Developer-only · Concepts take time to learn

Python framework for orchestrating role-based multi-agent crews.

Agent framework · Pricing: Open source; hosted platform (see site)

Pros: Intuitive role/task model · Fast to prototype

Cons: Less low-level control than LangGraph

TypeScript toolkit for building AI chat, streaming UIs and agents across model providers.

AI app toolkit · Pricing: Open source

Pros: Provider-agnostic · Great streaming UI helpers

Cons: TypeScript/JS only

Fair-code workflow automation with native AI agent nodes.

Workflow automation · Pricing: Self-host option + cloud plans (see site)

Pros: Self-hostable · Powerful AI agent nodes · Code when you need it

Cons: Steeper than Zapier · Self-hosting is on you