A memory-first platform for agents that persist across sessions
Advisor score
Documented editorial evaluation
The decision
Letta earns a shortlist for teams that genuinely need persistent agents and can govern memory as sensitive application data. Start with synthetic identities, explicit memory-write rules, access isolation, corrections, and a tested export and deletion path.
Best for
Long-running stateful agents; Editable agent memory.
Choose something else if
Sensitive memory without deletion controls; Simple stateless assistants
Evidence
Editorial research pending · 8.0/10
Pricing checked
See current vendor pricing · 2026-09-02
Free access is available, with limits.
Yes. Open-source and local options avoid a Letta software fee, while models and infrastructure still cost money.
Community choice
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Letta gives agents editable persistent memory, but memory quality, deletion, model data paths, and long-running costs need controlled testing.
Letta earns a shortlist for teams that genuinely need persistent agents and can govern memory as sensitive application data. Start with synthetic identities, explicit memory-write rules, access isolation, corrections, and a tested export and deletion path.
Create 100 synthetic users with changing preferences, contradictions, aliases, restricted facts, and deletion requests. Measure recall precision, stale-memory rate, cross-user leakage, correction success, deletion coverage, context growth, latency, and cost.
Personal Recommendation
Letta earns a shortlist for teams that genuinely need persistent agents and can govern memory as sensitive application data. Start with synthetic identities, explicit memory-write rules, access isolation, corrections, and a tested export and deletion path.
Try the recommendation
Memory-first architecture
Overall Score
Editorial Review Framework
Overall Score
8.0
Ease of Use
7.6
AI Quality
8.0
Features
8.2
Speed
7.8
Integrations
8.2
Value for Money
8.0
Customer Support
7.4
Learning Curve
7.2
Recommended Because…
Memory-first architecture
Scores use a 0-10 editorial scale: 9–10 exceptional, 8–8.9 strong, 7–7.9 capable with material tradeoffs, 6–6.9 limited fit, and below 6 not recommended. Scores publish only when a documented evaluation supports them.
Reusable trial worksheet
Turn this review’s buyer test into evidence. Your entries autosave only in this browser and are never added to shared shortlist links.
Confirm the tool meets every must-have workflow and stakeholder requirement.
Review starting point: Long-running stateful agents; Editable agent memory; Local and cloud deployment
Run the same representative work you would use in production; do not score a polished demo.
Review starting point: Complete three to five representative tasks with known acceptable outcomes and compare them with your current process.
Calculate the effective cost per accepted result, including usage, review, corrections, and required add-ons.
Review starting point: Letta's open-source server can be self-hosted without a software subscription. Cloud usage, model calls, storage, hosting, backups, and operations remain cost drivers; enterprise customers can use documented bring-your-own provider keys. Reviewed September 2, 2026.
Define an acceptance threshold, test known answers and edge cases, and record every correction.
Review starting point: Editorial quality signals: features 4.1/5; AI quality 4.0/5. Validate these signals in your own work.
Verify what data enters the product, who can access it, how long it is retained, and whether it trains models.
Review starting point: Use approved low-risk data first. Check roles, consent, deletion, subprocessors, model-training settings, and the contract—not only the marketing page.
Test the real handoffs, permissions, failure states, and export path your team depends on.
Review starting point: Python, TypeScript, OpenAI, Anthropic, MCP, REST API
Record training, governance, reliability, accessibility, ownership, and change-management risks before rollout.
Review starting point: Bad memories can persist; Self-hosters own operations; Cloud and model costs vary
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Evaluation
Research-based
Price posture
freemium
Reviewed
2026-09-02
No authentic product screenshot is published for this review. DiscoverAI does not use generated interface images as product evidence.
Editorial freshness
Pricing and material product claims were checked September 2, 2026.
Community evidence
Structured, editor-moderated experience—not star ratings. This complements our independent review and never changes its score.
No approved community evidence yet. Be the first verified user to contribute.
Its open-source server can be self-hosted without a subscription; models, storage, infrastructure, and operations still cost money.
It treats memory and context as persistent, editable agent state rather than only transient chat history.
Yes. Letta documents local and self-hosted paths as well as managed cloud.
Not automatically. Content sent to external model or tool providers follows those providers' data paths.
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