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Hindsight

Open-source agent memory that retains, recalls, and reflects.

Category
Memory
Pricing
FREEMIUM
Source
Open core
Hosting
Hybrid
Platforms
API
Models
BYO key / model
Verified
Jun 20, 2026

Hindsight is an open-source memory system for AI agents that works like human memory — organizing world facts, agent experiences, entity summaries, and evolving beliefs into four networks. Its retain/recall/reflect operations let agents reflect on past runs and update beliefs instead of repeating mistakes. It was built by Vectorize with Virginia Tech and The Washington Post.

Pros & cons

  • Reflection: agents learn from experience
  • Top LongMemEval accuracy (91.4%)
  • MIT-licensed, self-hostable
  • Human-like memory networks
  • Managed Hindsight Cloud option
  • New (2026), small ecosystem so far
  • Tied to Vectorize's stack and roadmap
  • Reflection adds LLM cost and latency

Tags

Further reading

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