MCP

Lag exposes a Model Context Protocol (MCP) server that lets AI assistants interact with your account - managing friends, reading and sending messages, browsing servers, and configuring robots.

Connecting

Claude Desktop

Add the following to your Claude Desktop MCP configuration:

{
  "mcpServers": {
    "lag": {
      "url": "https://api.trylag.com/mcp/",
      "transport": "streamable-http"
    }
  }
}

On first use, Claude Desktop will open your browser to authenticate via Discord or Google OAuth. Once authenticated, the connection persists across sessions.

Claude Code

Add the Lag MCP server from the command line:

claude mcp add lag --transport http https://api.trylag.com/mcp/

Other MCP Clients

Any MCP-compatible client can connect using the streamable HTTP transport. The server publishes OAuth metadata at:

GET https://api.trylag.com/mcp/.well-known/oauth-authorization-server

This returns the authorization, token, and registration endpoints needed for the OAuth flow. Clients that support MCP OAuth will handle this automatically.

Authentication Flow

The MCP server uses OAuth 2.0 with Supabase as the identity provider. The full flow:

Client registration - Your MCP client sends a POST to /mcp/register with its redirect URIs. The server returns a client_id.
Authorization - The client redirects you to /mcp/authorize with the client_id, redirect_uri, and an optional provider parameter (discord or google, defaults to Discord).
OAuth login - You authenticate with Discord or Google through Supabase.
Callback - Supabase redirects back to /mcp/callback, which issues an authorization code and redirects to your client’s redirect_uri.
Token exchange - The client exchanges the authorization code for an access token via POST /mcp/token.
Ready - The client includes the access token as a Bearer token on all subsequent POST /mcp/ requests.

Available Tools

Once connected, these tools are available to the AI assistant:

Friends

Tool	Description
`list_friends`	List all accepted friends
`list_friend_requests`	List pending incoming and outgoing requests
`send_friend_request`	Send a friend request by username
`accept_friend_request`	Accept an incoming request
`decline_friend_request`	Decline an incoming request
`remove_friend`	Remove an existing friendship
`block_user`	Block a user

Direct Messages

Tool	Description
`list_dm_conversations`	List all DM conversations sorted by activity
`read_dm_messages`	Read messages in a DM conversation (up to 100)
`send_dm_message`	Send a message in a DM conversation

Servers

Tool	Description
`list_servers`	List all servers you are a member of
`get_server_details`	Get server info including rooms, members, and your role
`read_room_messages`	Read messages in a server room (up to 100)
`send_room_message`	Send a message to a server room

Profile

Tool	Description
`get_my_profile`	Get your profile information
`update_my_profile`	Update your display name

Robots

Tool	Description
`list_robots`	List robots configured for a server
`get_robot_details`	Get a specific robot’s configuration
`create_robot`	Create a new robot (server owner only)
`update_robot`	Update a robot’s configuration (server owner only)
`delete_robot`	Delete a robot (server owner only)
`regenerate_robot_key`	Regenerate a robot’s API key (server owner only)
`get_robot_logs`	Get recent event delivery logs for a robot

Documentation

Tool	Description
`get_docs`	Retrieve Lag documentation. No params returns the table of contents. Specify `section` and `page` for specific content.

Protocol Details

Transport: Streamable HTTP (stateless) - each request is independent
Endpoint: POST https://api.trylag.com/mcp/
Auth: Authorization: Bearer <access-token> header on every request
Rate limit: 100 requests per minute per user
Methods not supported: GET /mcp/ and DELETE /mcp/ return 405 (stateless mode)