Tool UseModel Context Protocol

Connecting Letta to MCP Servers

Connect Letta agents to tools over Model Context Protocol (MCP)

Letta no longer supports legacy .json configuration files. Use the ADE or API/SDK.

Letta supports three MCP transport types depending on your deployment and use case.

Connection Methods

  • ADE: Point-and-click server management via web interface
  • API/SDK: Programmatic integration for production

Transport Types

  • Streamable HTTP (Recommended): Production-ready with auth support. Works on Cloud + self-hosted.
  • SSE (Legacy): Deprecated but supported for compatibility.
  • stdio (Self-hosted only): Local development and testing.
TransportCloudSelf-hosted
Streamable HTTP✅✅
SSE✅✅
stdio❌✅

Tool Execution Flow

Quick Start

  1. Choose transport type based on your deployment
  2. Connect via ADE: Tool Manager → Add MCP Server
  3. Attach tools to agents

See remote servers or local servers for detailed setup.