Letta

What is Letta?

Letta, previously known as MemGPT, is a platform for stateful AI agents that keep their memory and learn across sessions. You can run agents from an interactive terminal interface, in a browser at chat.letta.com, through channels such as Slack, Telegram and Discord, or embed them in a TypeScript app with the Letta Agent SDK. Local or self-hosted agents run on the App Server, and Letta Cloud keeps memory, identity and conversations available across computers. Pricing is split by how you use it. Individuals can start free with their own API keys, Pro costs $20 per month with a Letta Auto usage quota and up to 20 stateful agents, Teams Pro is $20 per seat per month with shared agents and access control, and the API plan is $20 per month plus usage-based charges for unlimited agents. Enterprise is custom, and all plans support bringing your own model keys.

Use cases

• Build agents with persistent memory
• Chat with a stateful agent in the terminal
• Embed agents in a TypeScript app
• Reach an agent from Slack or Discord
• Run agents on a self-hosted server
• Share custom agents across a team
• Use an agent for long coding sessions

Who it's for

• AI developers
• Engineering teams
• Coding agent users
• Enterprises

Why use Letta

• Agents remember earlier work, so you are not rebuilding context at the start of every session.
• You can start free with your own model keys or an existing coding plan before spending anything.
• The same agent is reachable from the terminal, the web and chat channels, so you can pick the surface that fits.
• Developer plans have no cap on the number of agents, with charges based on usage.
• Teams can share agents and set permissions instead of each person keeping their own copy.

Letta features

• Stateful agents with memory that persists across sessions
• Interactive terminal interface and CLI
• Web chat at chat.letta.com
• Letta Agent SDK for TypeScript
• App Server for local or self-hosted agents
• Channels for Slack, Telegram and Discord
• Letta Auto model routing with Auto Chat and Auto Fast
• Bring your own API keys and external coding plans
• Shared agents with access control on Teams Pro
• Remote sandboxes on the Pro plan

Letta integrations

• Discord
• ChatGPT
• Codex
• Kimi
• Z.AI
• MCP

How to get started with Letta

1. Install the Letta terminal app from npm, or open chat.letta.com in a browser.
2. Pick a model with Letta Auto, or connect your own API key or external coding plan with the connect command.
3. Create a stateful agent and work with it; its memory is kept and improves across sessions.
4. Add channels such as Slack, or embed the agent in a TypeScript app with the SDK.
5. Upgrade to Pro, Teams Pro or an API plan when you need larger quotas, sharing or unlimited agents.

Letta limitations

• Free plan is limited to 3 stateful agents and limited Letta Auto usage
• Pro allows up to 20 stateful agents
• Heavy coding or computer-use workloads drain quota faster and can need pay-as-you-go credits
• Adding members to an organization requires a Teams Pro account

Letta pricing

Yes, Letta has a free plan. Paid plans start at $20 per month, according to the official pricing page on 24 Oct 2026.

Letta plans

• Free

  $0/month

  • Limited agents
  • 5 MiB of storage per memory repository
  • Limited usage of Letta Auto
  • Bring your own API keys and external coding plans

• Pro

  $20/month

  • Letta Auto weekly and monthly quota
  • Pay-as-you-go overage
  • Up to 20 stateful agents
  • 50 MiB of storage per memory repository

• API Plan

  $20/month

  plus usage-based charges

  • Unlimited agents
  • $0.10 per active agent per month
  • $0.00015 per second of tool execution
  • API key authentication

• Teams Pro

  $20/seat/month

  • Add teammates to your organization
  • Letta Auto weekly and monthly quota
  • Share agents and set access control

• Enterprise

  Custom

  • Volume-based pricing
  • Increased quotas
  • Role-based access control
  • SAML/OIDC SSO
  • Dedicated support

Plans as listed on the official pricing page on 24 Oct 2026. Prices can change and may vary by country or exclude tax. Check the official pricing page.

Letta alternatives

The main Letta alternatives listed on Debuly are LangGraph, CrewAI, Mem0, Zep, OpenAI Agents SDK and AutoGen. The table compares pricing and platforms; order is A–Z.

1. 

   AutoGen

   Microsoft's MIT-licensed Python and .NET framework for multi-agent AI apps, now archived; new projects are pointed to Microsoft Agent Framework.

   Developer platformsAutomation and agentsCoding
   Open sourceVisit AutoGen (official site)
2. 

   CrewAI

   Multi-agent framework and platform for building AI agent crews in Python or a visual editor, then deploying and monitoring them.

   Developer platformsAutomation and agentsCoding
   Open sourceVisit CrewAI (official site)
3. 

   LangGraph

   Low-level open-source orchestration framework and runtime for building stateful, long-running AI agents as graphs.

   Developer platformsAutomation and agentsCoding
   Open sourceVisit LangGraph (official site)
4. 

   Mem0

   Memory layer for AI agents and apps, available as an open-source package or a managed platform that keeps user context across sessions.

   Developer platformsAutomation and agentsCoding
   FreemiumVisit Mem0 (official site)
5. 

   OpenAI Agents SDK

   Open-source Python framework for building multi-agent workflows with tools, handoffs, guardrails, tracing, sandboxes and voice agents.

   Developer platformsAutomation and agentsCoding
   Open sourceVisit OpenAI Agents SDK (official site)
6. 

   Zep

   Managed memory and context platform for AI agents, built on the Graphiti knowledge graph, with Python, TypeScript and Go SDKs.

   Developer platformsAutomation and agents
   FreemiumVisit Zep (official site)

Letta FAQ

Sources & verification

Facts on this page come from the official sources below, each with the date we read it. Written by Debuly; the vendor did not review this page.

Image credits

• Logo: from docs.letta.com · fetched 24 Oct 2026 · Vendor trademark, used only to identify the product; removed on request
• Cover: none collected yet, so a generated tile is shown.

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