Letta Integration

Letta (formerly MemGPT) is a framework for building stateful AI agents with long-term memory. It manages context windows intelligently, allowing agents to maintain persistent conversations and knowledge across sessions.

Letta supports custom LLM endpoints, letting you connect LLM API for agent intelligence.

Prerequisites

An LLM API account with an API key
Letta installed or accessible

Setup

Get Your LLM API Key

Log in to your LLM API dashboard
Click Create Key to Start
Copy your new API key immediately — it will only be shown once
Store the key securely (e.g., in a password manager or .env file)

LLM API is an OpenAI-compatible gateway that gives you access to dozens of AI models through a single API key and endpoint.

Configure LLM API in Letta

Set environment variables:

export OPENAI_API_KEY="your-llm-api-key-here"
export OPENAI_API_BASE="https://api.llmapi.ai/v1"

Or configure in Letta's config:

letta configure
\# When prompted:
\# LLM Provider: openai
\# Base URL: https://api.llmapi.ai/v1
\# API Key: your-llm-api-key-here

Create and run agents --- they will use LLM API.

Test the Integration

Verify that Letta can successfully communicate with LLM API by sending a test request. All requests will now be routed through LLM API.

Letta's memory management works best with models that have strong instruction following. LLM API gives you access to the best options.

Benefits of Using LLM API with Letta

Multi-Provider Access: Use models from OpenAI, Anthropic, Google, and more through a single API
Cost Control: Track and limit your AI spending with detailed usage analytics
Unified Billing: One account for all providers instead of managing multiple API keys
Caching: Reduce costs with response caching for repeated requests

View all available models on the models page.