Letta

Letta is a stateful agent platform from the researchers behind MemGPT. Its core idea is that agents should not live only inside one context window. They should have persistent memory, stored state, tools, and the ability to learn across sessions without starting over every time.

For a technical founder, that is useful when the agent needs to remember customers, projects, preferences, files, or prior work. Letta gives you an API, agent development environment, and Letta Code CLI so you can build agents that operate more like long-running services than one-off prompts.

The warning is that memory is a product decision, not a magic feature. A persistent agent can preserve useful context, but it can also preserve stale assumptions, sensitive data, or bad habits. Use Letta when continuity is the product, and pair it with traces, evals, and clear memory boundaries. If your job is a simple repeatable workflow, n8n or Make is usually a cleaner starting point.