L
Letta
38
Stack Score
Editorial pick✓ Verified working
Letta
Stateful AI agent framework with memory.
Try Letta✓ Free trial available
Best for
Best for AI engineering teams building stateful + long-running agents.
At a glance
- Pricing
- freemium
- Setup time
- 1 day
- Learning curve
- steep
- Last verified
- 5/26/2026
What we love
- ✓Best stateful-agent framework
- ✓Memory abstractions are powerful
- ✓Truly OSS core
Where it falls short
- −Complex setup for novices
- −Best for serious AI app builders
- −Hosted tier costs ramp
Pricing
✓ Pricing verified Jun 21, 20262 tiers
OSS
$0
perpetual
- ✓Self-host
Cloud
Custom
per agent/month
- ✓Hosted
- ✓SLA
Overview
Letta (formerly MemGPT) is a stateful AI agent framework — agents have long-term memory, can be paused/resumed, and run as services. OSS Python + hosted cloud.
Key features
- ●Stateful agents with memory
- ●Pause + resume agents
- ●Multi-agent + tools
- ●OSS Python core
- ●Hosted cloud option
Best use cases
Long-running AI agents
Build agents that maintain state + memory across days or weeks.
Multi-agent orchestration
Coordinate multiple agents with shared memory.
Integrations
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