Graphiti vs Letta
Updated March 10, 2026
Overview
Graphiti is an open-source temporal knowledge graph engine built by the Zep team. It creates dynamic, time-aware knowledge graphs from conversational and unstructured data, enabling agents to maintain evolving memory with temporal reasoning. Graphiti powers many agent memory implementations and is often used alongside Zep for graph-based recall.
Letta (formerly MemGPT) is an open-source framework for building AI agents with long-term memory and self-editing capabilities. It implements a virtual context management system that allows LLMs to manage their own memory hierarchy, enabling persistent state, unbounded context, and adaptive memory across conversations.
Strengths and tradeoffs
What each tool does well, and the limitations to keep in mind.
Pros
- Production-ready platform
- Good performance
- Active development
- Strong features
Cons
- Enterprise pricing varies
- Setup complexity
- Learning curve required
Pros
- Advanced structured memory with entities, facts, and timelines
- Extreme interpretability with human-readable memory
- Strong balance between flexibility and production readiness
- USD 10M seed funding validates technology approach
Cons
- Requires architectural decisions around vector stores and RAG
- Not a plug-and-play solution—needs developer expertise
- Community feedback suggests learning curve for optimal use
Compare Graphiti and Letta on your own traffic
Respan lets you trace LLM and agent calls across any model or framework, A/B test prompts on production traffic, and route requests across 500+ models through one gateway.