--- title: "Letta vs OpenAI Agents SDK: Which is Better in 2026? | App Stack Builder" description: "Letta vs OpenAI Agents SDK compared for 2026 — pricing, free tiers, features, pros & cons. See which agent framework tool is the better fit for your startup." source: https://appstackbuilder.com/compare/letta-vs-openai-agents-sdk retrieved: 2026-10-29 --- ![](https://appstackbuilder.com/logos/letta.png) vs ![](https://www.google.com/s2/favicons?domain=openai.github.io&sz=128) # Letta vs OpenAI Agents SDK: Which is Better in 2026? Agent Framework Choosing between [Letta](https://appstackbuilder.com/tools/letta) and [OpenAI Agents SDK](https://appstackbuilder.com/tools/openai-agents-sdk)? Both are popular agent framework tools. Below we compare them on pricing, free tiers, features, and pros & cons so you can pick the right fit for your stack. Letta is for: Teams building agents that must remember users and context across sessions and restarts, with memory as the core design. OpenAI Agents SDK is for: Teams that want to ship agents quickly with few abstractions: agents, tools, handoffs and guardrails, with tracing built in. Quick verdict There’s no single winner; pick on your constraint. Choose Letta if your agent must remember users and past sessions over weeks or months. Choose OpenAI Agents SDK if you want to ship a working agent with minimal boilerplate. ## Letta vs OpenAI Agents SDK — Side by Side | | Letta | OpenAI Agents SDK | | --------------------- | ------------------------------------------------------------------------ | ------------------------------------------------------------------- | | Category | Agent Framework | Agent Framework | | What it is | Agent server and SDKs: agents with persistent memory | Code library: lightweight agent SDK | | Languages | Python and TypeScript SDKs | Python, TypeScript | | Licence | Apache 2.0 | MIT | | Managed / paid option | Letta API: free tier, Pro $20/month plus usage | None; you pay for OpenAI API usage | | Project status | Active | Active | | Pricing | Free · paid from $20/mo | Free | | Starting price | Free tier available | Free tier available | | Free tier | ✓ | ✓ | | Rating | 4.0 | 4.5 | | Best for | Agent Framework — long-term memory, stateful agents, self-host or hosted | Agent Framework — minimal abstractions, fast to ship, OpenAI models | ## Pros & Cons ![](https://appstackbuilder.com/logos/letta.png) [Letta](https://appstackbuilder.com/tools/letta) * ✓Memory is the design centre, not an add-on * ✓Agents survive restarts with state intact * ✓Comes from the MemGPT paper * ✗Younger project with a moving API * ✗Memory model is opinionated ![](https://www.google.com/s2/favicons?domain=openai.github.io&sz=128) [OpenAI Agents SDK](https://appstackbuilder.com/tools/openai-agents-sdk) * ✓Very low boilerplate, fast to ship * ✓Production-ready with tracing * ✓Backed by OpenAI * ✓Python & TypeScript support * ✗Best experience tied to OpenAI models * ✗Lighter on complex orchestration than LangGraph ## Key Features Compared ### Letta * ✓Persistent, self-editing agent memory (from the MemGPT research) * ✓Agents keep their state across restarts * ✓Self-hosted server, or the hosted Letta API * ✓Hosted plans: free tier and Pro at $20 a month with pay-as-you-go usage * ✓Letta Code, an open-source coding agent with memory across sessions * ✓Apache 2.0 licence ### OpenAI Agents SDK * ✓Small set of primitives: agents, tools, handoffs and guardrails * ✓Built-in tracing * ✓Sandbox execution for agents that run code and use a filesystem (April 2026 update) * ✓Other models through the LiteLLM extension (beta) or any OpenAI-compatible endpoint * ✓Python and TypeScript * ✓MIT licence ### Choose Letta if… * ✓Your agent must remember users and past sessions over weeks or months. * ✓You want agents that keep state when the process restarts. * ✓You want the choice of self-hosting or a hosted API. [Letta review & pricing ](https://appstackbuilder.com/tools/letta) ### Choose OpenAI Agents SDK if… * ✓You want to ship a working agent with minimal boilerplate. * ✓You mainly use OpenAI models and want first-party support. * ✓Your agents run code and need a sandbox from the same SDK. [OpenAI Agents SDK review & pricing ](https://appstackbuilder.com/tools/openai-agents-sdk) ## Frequently Asked Questions Is Letta better than OpenAI Agents SDK?⌄ There’s no single winner; pick on your constraint. Choose Letta if your agent must remember users and past sessions over weeks or months. Choose OpenAI Agents SDK if you want to ship a working agent with minimal boilerplate. What is the difference between Letta and OpenAI Agents SDK?⌄ What it is — Letta: Agent server and SDKs: agents with persistent memory. OpenAI Agents SDK: Code library: lightweight agent SDK. Languages — Letta: Python and TypeScript SDKs. OpenAI Agents SDK: Python, TypeScript. Licence — Letta: Apache 2.0\. OpenAI Agents SDK: MIT. Managed / paid option — Letta: Letta API: free tier, Pro $20/month plus usage. OpenAI Agents SDK: None; you pay for OpenAI API usage. Letta vs OpenAI Agents SDK: which is cheaper?⌄ Letta pricing: Free · paid from $20/mo. OpenAI Agents SDK pricing: Free. Confirm current pricing on each tool's official site, as plans change. Which is rated higher, Letta or OpenAI Agents SDK?⌄ In our catalog, Letta rates 4.0 out of 5 and OpenAI Agents SDK rates 4.5 out of 5, so OpenAI Agents SDK has a slight edge on reviews. When should I skip both Letta and OpenAI Agents SDK?⌄ Skip Letta if you only need short-lived task agents. A lighter SDK is simpler. Skip OpenAI Agents SDK if you need complex orchestration with explicit state and checkpoints. LangGraph covers that. Sources · tool facts checked October 2026 1. 1.[Letta Code (Letta docs)docs.letta.com ](https://docs.letta.com/letta-code) 2. 2.[The next evolution of the Agents SDK (OpenAI)openai.com ](https://openai.com/index/the-next-evolution-of-the-agents-sdk/) 3. 3.[Using any model via LiteLLM (Agents SDK docs)openai.github.io ](https://openai.github.io/openai-agents-python/models/litellm) See more options in our guide to the [best agent framework tools for startups](https://appstackbuilder.com/categories/agent-framework). ## Still not sure which to pick? Get a free, AI-powered tech stack — including the best agent framework pick for your budget and team — in 60 seconds. [Build my stack free ](https://appstackbuilder.com/build-stack)