Production-ready MCP server bridging Claude and Letta.ai agents
Production-ready MCP server bridging Claude and Letta.ai agents. That is what the letta mcp server brings to an AI assistant: the same capability, reachable through the Model Context Protocol rather than a separate app or dashboard.
Universal MCP server connecting any AI client to Letta.ai's powerful stateful agents.
Because this one is hosted, setup is mostly authentication — you point your client at the endpoint and approve access. Nothing runs on your machine, so there is no runtime to keep patched.
The server publishes 7 tools. What each one is for:
letta_list_tools — List available toolsletta_attach_tool — Add tools to agentsletta_create_tool — Create custom toolsletta_set_tool_rules — Configure workflow constraintsCursor — // Use in Cursor Chat Use letta_create_agent to set up a development assistant for this projectReplit — The Replit tool exposed by this serverExamples — The Examples tool exposed by this serverConfiguration is passed through the environment: LETTA_API_KEY, LETTA_BASE_URL. Treat anything key-shaped as a real credential — scope it to the minimum the server needs, and rotate it if it ever lands in a shared config.
This sits in the developer tooling group, where several servers overlap in what they claim to do but differ sharply once you actually set them up. Letta's toolset — letta_list_tools, letta_attach_tool, letta_create_tool and 4 more — is a fair guide to whether it matches your workflow.
We check each listing at SyncDev against the project's documentation before it goes live — if something here drifts out of date, it is a bug worth reporting.
| Tool | What it does |
|---|---|
| letta_list_tools | List available tools |
| letta_attach_tool | Add tools to agents |
| letta_create_tool | Create custom tools |
| letta_set_tool_rules | Configure workflow constraints |
| Cursor | // Use in Cursor Chat Use letta_create_agent to set up a development assistant for this project |
| Replit | The Replit tool exposed by this server. |
| Examples | The Examples tool exposed by this server. |
{
"mcpServers": {
"letta": {
"command": "uvx",
"args": ["letta-mcp-server"],
"env": {
"LETTA_API_KEY": "your-value",
"LETTA_BASE_URL": "your-value"
}
}
}
}Add to claude_desktop_config.json, then restart Claude Desktop.
| Variable | Description | Required |
|---|---|---|
| LETTA_API_KEY | Credential the server authenticates with. | Yes |
| LETTA_BASE_URL | Endpoint or connection string the server talks to. | Yes |
Kill hallucinated APIs — version-accurate, up-to-date library documentation injected straight into context.
Microsoft's official browser automation server — drive a real browser through the accessibility tree, no screenshots needed.
GitHub's official server — repos, issues, pull requests, Actions and code security, straight from your assistant.
Issue tracking at the speed of conversation — Linear's official hosted server with OAuth and zero install.
Local repository surgery — status, diffs, commits, branches and history for any repo on disk.
Timezone sanity for AI — current time anywhere and correct conversions, without the model doing date math.