Tools and libraries for building AI agents
Comparison Matrix
| Framework |
Focus |
Best For |
Learning Curve |
| LangGraph |
Graph orchestration |
Complex workflows |
Steep |
| CrewAI |
Role-based multi-agent |
Content gen, fast deploy |
Moderate |
| Microsoft Agent Framework |
Enterprise |
.NET/Azure shops |
Moderate |
| OpenAI Agents SDK |
OpenAI ecosystem |
OpenAI-first apps |
Easy |
| LlamaIndex |
RAG-centric |
Knowledge retrieval |
Moderate |
LangChain / LangGraph
|
|
| GitHub Stars |
80K+ |
| Production Users |
Replit, Uber, Klarna |
| 2025 Guidance |
"Use LangGraph for agents" |
Architecture
Stateful graphs: nodes (functions), edges (flow), persistent state. Cyclical graphs, checkpointing, streaming.
Resources
CrewAI
|
|
| Funding |
$18M Series A (2025) |
| Revenue |
$3.2M (July 2025) |
| Scale |
100K+ executions/day |
| Customers |
150+ enterprise, 60% Fortune 500 |
Key Features
- Role-based "Crews"
- Native multimodal (2025)
- HIPAA/SOC2 certified
- 2 weeks to production (vs 2 months LangGraph)