---

What is this?

@letretro/mcp is the official Model Context Protocol package for LetRetro. It gives AI coding assistants direct access to your LetRetro workspace — boards, cards, retrospectives, and team data.

It runs in two modes:

Mode	What it does
install	Interactive CLI wizard that auto-configures your MCP clients
server (default)	Local MCP stdio server using the official MCP SDK — forwards requests to mcp.letretro.com

One install command, zero manual JSON editing.

---

Quick start

npx @letretro/mcp install

You'll be prompted for your LetRetro API key. The installer detects your installed MCP clients and writes the configuration — you pick which ones to set up.

  ╔══════════════════════════════════╗
  ║     LetRetro MCP Installer       ║
  ╚══════════════════════════════════╝

  Enter your LetRetro API Key: ••••••

  Detected clients:
    ✓ Claude Desktop
    ✓ Cursor
    ✓ VS Code
    ✓ OpenAI Codex CLI
    ✓ OpenCode
    ✓ Antigravity
    ✓ Hermes
    ✓ OpenClaw

  (Use space to select, enter to confirm)
  ✔ Select clients to configure:

  ✓ Claude Desktop: Updated ~/Library/Application Support/Claude/claude_desktop_config.json
  ✓ Cursor: Created ~/.cursor/mcp.json

  ╔══════════════════════════════════╗
  ║     LetRetro MCP Installed        ║
  ╚══════════════════════════════════╝

  Restart your MCP clients to start using
  LetRetro tools.

What gets configured

The installer adds a letretro server entry to your client's MCP config:

{
  "mcpServers": {
    "letretro": {
      "command": "npx",
      "args": ["-y", "@letretro/mcp"],
      "env": {
        "LETRETRO_API_KEY": "lr_..."
      }
    }
  }
}

Restart your AI coding tool and LetRetro tools are automatically available.

---

Supported clients

The installer auto-detects these clients and writes the correct config for each:

Client	Auto-detect	Config file written	Format
Claude Desktop	✅ macOS/Linux	claude_desktop_config.json	JSON
Cursor	✅	~/.cursor/mcp.json	JSON
VS Code	✅ binary + config	.vscode/mcp.json	JSON
OpenAI Codex CLI	✅	~/.codex/config.toml	TOML
OpenCode	✅	~/.config/opencode/opencode.json	JSON
Antigravity	✅	~/.gemini/config/mcp_config.json	JSON
Hermes	✅	~/.hermes/config.yaml	YAML
OpenClaw	✅	~/.openclaw/openclaw.json	JSON
Windsurf	✅ config check	~/.codeium/windsurf/mcp_config.json	JSON
Continue	✅	~/.continue/config.json	JSON

Don't see your client? Open an issue.

---

How it works

AI Assistant                npx @letretro/mcp              mcp.letretro.com
     │                            │                              │
     │  MCP JSON-RPC over stdio   │                              │
     │  (initialize, tools/list,  │                              │
     │   tools/call, ...)         │                              │
     │──────────────────────────> │                              │
     │                            │  HTTP POST (Bearer token)    │
     │                            │  (forwarded JSON-RPC)        │
     │                            │ ────────────────────────────>│
     │                            │                              │
     │                            │  JSON-RPC response           │
     │                            │ <────────────────────────────│
     │  MCP JSON-RPC response     │                              │
     │ <──────────────────────────│                              │

The local process is a proper MCP stdio server built with the official MCP SDK. It:

• Handles the full MCP handshake (initialize, ping, notifications/*)
• Implements tools/list with a cached response from the remote server
• Forwards tools/call requests to mcp.letretro.com and returns results
• Supports graceful shutdown via SIGTERM/SIGINT
• Reads LETRETRO_API_KEY and an optional LETRETRO_MCP_URL override from the environment

All MCP tools, resources, and prompts are implemented server-side on mcp.letretro.com, so you get updates instantly — no package upgrade needed.

---

Manual setup

If you prefer to configure clients manually instead of using the installer, add the following to your client's MCP config file.

Claude Desktop / Cursor / Antigravity / OpenClaw / Windsurf / Continue:

{
  "mcpServers": {
    "letretro": {
      "command": "npx",
      "args": ["-y", "@letretro/mcp"],
      "env": {
        "LETRETRO_API_KEY": "your_key_here"
      }
    }
  }
}

VS Code:

{
  "servers": {
    "letretro": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@letretro/mcp"],
      "env": {
        "LETRETRO_API_KEY": "your_key_here"
      }
    }
  }
}

OpenCode:

{
  "mcp": {
    "letretro": {
      "type": "local",
      "command": ["npx", "-y", "@letretro/mcp"],
      "enabled": true,
      "environment": {
        "LETRETRO_API_KEY": "your_key_here"
      }
    }
  }
}

OpenAI Codex CLI:

[mcp_servers.letretro]
command = "npx"
args = ["-y", "@letretro/mcp"]

[mcp_servers.letretro.env]
LETRETRO_API_KEY = "your_key_here"

Hermes:

mcp_servers:
  letretro:
    command: "npx"
    args:
      - "-y"
      - "@letretro/mcp"
    env:
      LETRETRO_API_KEY: "your_key_here"

---

Environment variables

Variable	Default	Description
LETRETRO_API_KEY	—	Your LetRetro API key (required)
LETRETRO_MCP_URL	https://mcp.letretro.com	Override the remote MCP server URL (for testing)
LETRETRO_VALIDATE_URL	https://mcp.letretro.com	URL used for API key validation during install

---

Development

git clone https://github.com/LetRetroHQ/mcp-cli.git
cd letretro-mcp/mcp-npm
pnpm install
pnpm dev          # watch mode
pnpm build        # production build
pnpm typecheck    # type checking
pnpm test         # run tests

Project structure

src/
├── index.ts           # Entry point — routes to install or server mode
├── install.ts         # Interactive installer (prompt → detect → configure)
├── server.ts          # MCP stdio server (MCP SDK) — forwards to mcp.letretro.com
├── clients/
│   ├── index.ts       # Client registry and detection helpers
│   ├── claude.ts      # Claude Desktop
│   ├── cursor.ts      # Cursor
│   ├── vscode.ts      # VS Code
│   ├── codex.ts       # OpenAI Codex CLI (TOML config)
│   ├── opencode.ts    # OpenCode
│   ├── antigravity.ts # Google Antigravity
│   ├── hermes.ts      # Hermes Agent (YAML config)
│   ├── openclaw.ts    # OpenClaw
│   ├── windsurf.ts    # Windsurf
│   └── continue.ts    # Continue
└── utils/
    ├── paths.ts       # OS-aware config file paths
    ├── toml.ts        # TOML serializer for Codex config
    └── yaml.ts        # YAML serializer for Hermes config

---

Contributing

Contributions are welcome! Whether it's adding support for a new MCP client, improving the installer, or fixing a bug:

1. Fork the repo
2. Create a feature branch (git checkout -b feat/my-feature)
3. Commit your changes (git commit -am 'feat: add support for...')
4. Push to the branch (git push origin feat/my-feature)
5. Open a Pull Request

See CONTRIBUTING.md for detailed guidelines.

---

License

MIT © LetRetro

---