Letta

Freemium

A platform for building stateful agents with persistent memory and transparent reasoning.

Letta is an open-source platform for building stateful agents with persistent memory and transparent reasoning. It features a developer platform for API integration and a coding harness for persistent development sessions. The tool is designed for developers and power users, offering tiers ranging from a free BYOK plan to enterprise solutions with SSO and RBAC (verified: 2026-01-29).

Jan 29, 2026
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Pricing: Freemium
Last verified: Jan 29, 2026
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Key facts

Pricing

Freemium

Use cases

Developers building applications that require agents to maintain persistent memory and learn about users over time (verified: 2026-01-29)., Software engineers using a memory-first coding harness to work with agents that persist across different sessions (verified: 2026-01-29)., Teams creating production-ready agentic workflows that remain model-agnostic while utilizing stateful reasoning capabilities (verified: 2026-01-29).

Strengths

The platform provides a stateful agent architecture that allows agents to remember and learn about users over time (verified: 2026-01-29)., Users can connect their own LLM API keys to run agents locally or through the Letta Developer Platform (verified: 2026-01-29)., The system supports a memory-first coding harness called Letta Code which enables portable agents across different models (verified: 2026-01-29).

Limitations

The Free plan limits users to a maximum of three stateful agents for their development projects (verified: 2026-01-29)., Access to frontier models on the Letta API requires a paid Pro plan subscription starting at twenty dollars monthly (verified: 2026-01-29).

Last verified

Jan 29, 2026

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Strengths

  • The platform provides a stateful agent architecture that allows agents to remember and learn about users over time (verified: 2026-01-29).
  • Users can connect their own LLM API keys to run agents locally or through the Letta Developer Platform (verified: 2026-01-29).
  • The system supports a memory-first coding harness called Letta Code which enables portable agents across different models (verified: 2026-01-29).

Limitations

  • The Free plan limits users to a maximum of three stateful agents for their development projects (verified: 2026-01-29).
  • Access to frontier models on the Letta API requires a paid Pro plan subscription starting at twenty dollars monthly (verified: 2026-01-29).

FAQ

What are the primary differences between the Free and Pro plans offered by the Letta platform?

The Free plan allows for three stateful agents and requires users to provide their own LLM API keys. In contrast, the Pro plan costs twenty dollars per month and provides unlimited stateful agents along with access to frontier models on the Letta API and 20,000 monthly credits (verified: 2026-01-29).

How does the Letta Code feature assist developers in maintaining agent persistence during software development?

Letta Code functions as a memory-first coding harness built on the Letta API. It allows developers to work with a persisted agent that learns over time instead of working in independent sessions, ensuring the agent remains portable across different models (verified: 2026-01-29).

What specific features are available for large organizations requiring enterprise-grade security and support?

The Enterprise plan is designed for organizations with high volume needs and includes role-based access control, Single Sign-On via SAML or OIDC, and dedicated support. It also features volume-based pricing and increased quotas to accommodate larger operational scales (verified: 2026-01-29).