Part 3: Agent Building Frameworks

Overview

Frameworks for building intelligent agents with reasoning, tool calling, and multi-agent systems.

Tool	Purpose	Best For	Complexity
Langchain	General agent framework	Most use cases	Medium
Llamaindex	Data & retrieval focus	RAG systems	Medium
Crewai	Multi-agent teams	Collaborative tasks	Medium
Autogen	Conversation orchestration	Complex workflows	High
Haystack	NLP pipelines	Production pipelines	High

Quick Comparison

Feature	LangChain	LlamaIndex	CrewAI	AutoGen
Integrations	300+	100+	50+	Limited
Learning Curve	Easy	Easy	Medium	Hard
Multi-agent	Yes	No	Yes	Yes
Tool Support	Excellent	Good	Good	Limited
Production Ready	Yes	Yes	Growing	Yes

Decision Tree

graph TD
    A["Building agent?"] -->|General purpose| B["LangChain"]
    A -->|Data/document focus| C["LlamaIndex"]
    A -->|Team of agents| D["CrewAI"]
    A -->|Complex reasoning| E["AutoGen"]
    A -->|Pipeline architecture| F["Haystack"]

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Next: Choose a framework to get started!