Agent Frameworks
Open-source libraries and SDKs for building custom AI agents from scratch.
Agent frameworks are open-source libraries and SDKs that give developers full control over how AI agents reason, use tools, and chain actions together. They are best for engineering teams that need custom agent logic, want to avoid vendor lock-in, or must integrate agents deeply into existing infrastructure. Evaluate the framework's LLM provider flexibility, community activity, documentation quality, and whether it supports the tool-calling and memory patterns your use case requires.
LangChain
The most popular framework for building LLM-powered applications and agents
AutoGen
Microsoft's framework for building multi-agent conversational AI systems
LlamaIndex
Data framework for connecting custom data to large language models
Claude Agent SDK
Anthropic's SDK for building production AI agents with Claude