langgraph vs letta
Side-by-side comparison of two AI agent tools
langgraphopen-source
Build resilient language agents as graphs.
lettaopen-source
Letta is the platform for building stateful agents: AI with advanced memory that can learn and self-improve over time.
Metrics
| langgraph | letta | |
|---|---|---|
| Stars | 28.0k | 21.8k |
| Star velocity /mo | 2.5k | 367.5 |
| Commits (90d) | — | — |
| Releases (6m) | 10 | 10 |
| Overall score | 0.8081963872278098 | 0.7466815254531132 |
Pros
- +Durable execution ensures agents automatically resume from exactly where they left off after failures or interruptions
- +Comprehensive memory system with both short-term working memory for ongoing reasoning and long-term persistent memory across sessions
- +Seamless human-in-the-loop capabilities allow for inspection and modification of agent state at any point during execution
- +Advanced persistent memory system that allows agents to learn and self-improve across sessions
- +Dual deployment options with both local CLI tool and cloud API for different use cases
- +Model-agnostic platform with comprehensive SDKs for Python and TypeScript development
Cons
- -Low-level framework requires more technical expertise and setup compared to high-level agent builders
- -Graph-based agent design paradigm may have a steeper learning curve for developers new to agent orchestration
- -Production deployment complexity may be overkill for simple chatbot or single-turn use cases
- -Requires Node.js 18+ for local CLI usage, limiting accessibility for some users
- -Cloud API requires API key and external service dependency for full functionality
- -Platform complexity may present learning curve for developers new to stateful agent concepts
Use Cases
- •Long-running autonomous agents that need to persist through system failures and operate over days or weeks
- •Complex multi-step workflows requiring human oversight, approval, or intervention at specific decision points
- •Stateful agents that must maintain context and memory across multiple sessions and interactions
- •Building long-term coding assistants that remember project context and user preferences across sessions
- •Creating customer service agents that maintain conversation history and learn from interactions
- •Developing research assistants that accumulate domain knowledge and improve recommendations over time