Agent frameworks: AI tools compared (October 2026)

NeMo Guardrails

Open-source NVIDIA toolkit for programmable guardrails in LLM applications, with Colang and input, output and dialog rails.

Tavily

Search API for AI agents with endpoints for web search, extraction, crawling and research, part of Nebius since February 2026.

Langflow

Open-source visual builder for AI agents and RAG flows that can be deployed as an API or MCP server.

Microsoft Agent Skills

Microsoft's skill collection for GitHub Copilot and other coding agents covering Azure SDKs and Microsoft Foundry, with custom agents and MCP configurations.

Prompt flow

Open-source development tools from Microsoft to build LLM flows from prompts and code, test them on datasets and check them in CI/CD.

Agno

Open-source framework and runtime (AgentOS) for agent platforms with memory, knowledge, teams and human approval.

DSPy

Open-source framework from Stanford NLP that generates prompts from Python code and tunes them against metrics with optimizers like GEPA.

Haystack

Open-source framework from Berlin-based deepset for AI agents, RAG pipelines and search, independent of the model provider.

LangGraph

Open-source framework from LangChain for stateful AI agents with durable execution, human-in-the-loop and memory.

CrewAI

Open-source Python framework for teams of role-based AI agents (Crews) and event-driven workflows (Flows).