Dify puts models, Knowledge, visual Workflows, Agents, Plugins, and application APIs in one workspace; this guide builds a minimal Workflow that can be tested, published, and called through the API, then explains when an Agent is actually warranted.
LlamaIndex and Haystack are code-first frameworks; RAGFlow and Dify are managed application platforms; R2R packages retrieval as an API service. Choose how much control your team needs over ingestion, retrieval, and operations before choosing a tool.
Sorted by GitHub Stars, a survey of 15 mainstream AI Agent frameworks in 2026 — their positioning, key features, and ideal use cases. Not a ranking — it's a map.