Letta vs Instructor

FeatureLettaInstructor
CategoryAI Agent FrameworksAI Development
PricingFree (open-source) + CloudFree (open-source)
GitHub Stars13,0009,000
PlatformsLinux, macOS, DockerLinux, macOS, Windows
Features
  • ✓ Long-term memory
  • ✓ Stateful agents
  • ✓ Tool use
  • ✓ Multi-model
  • ✓ Self-editing memory
  • ✓ Structured output
  • ✓ Pydantic models
  • ✓ Retry logic
  • ✓ Streaming
  • ✓ Multi-provider
Tags
memorystatefulagentsopen-source
structured-outputpydanticpythonopen-source