Connecting

The MCP client connects to the server over an SSE transport: a long-lived Server-Sent Events stream for server→client messages, plus a message endpoint for client→server requests. The client handles session setup and reconnection for you.

Connect and disconnect

import { McpClient } from "@divinci-ai/mcp";

const mcp = new McpClient({
  serverUrl: "https://mcp.divinci.app",
  autoReconnect: true,
  maxReconnectAttempts: 5,
});

await mcp.connect();
// ... use mcp.tools, mcp.listResources(), etc.
mcp.disconnect();

Connection state

getState() returns the current McpConnectionState:

disconnected → connecting → connected → authenticating → authenticated

(or error). Helpers:

mcp.getState();              // current state
mcp.isConnected();           // transport is up
await mcp.isAuthenticated(); // a valid Auth0 token is present

Events

mcp.on({
  onStateChange: (state) => console.log("state:", state),
  onToolsChanged: (tools) => refreshTools(tools),
  onResourcesChanged: (resources) => refreshResources(resources),
  onError: (err) => console.error(err),
});

Event	Fires when
`onStateChange(state)`	Connection state changes.
`onToolsChanged(tools)`	The server’s tool catalog changes.
`onResourcesChanged(resources)`	The server’s resource list changes.
`onError(error)`	A transport or protocol error occurs.

Reconnection

With autoReconnect: true (the default), dropped SSE connections reconnect with exponential backoff up to maxReconnectAttempts. Tune the base delay and ceiling through the constructor.

Server capabilities

After connecting, inspect what the server supports:

const caps = mcp.getServerCapabilities();
console.log(caps?.name, caps?.version, caps?.protocolVersion);

Health check

await mcp.ping(); // throws if the connection is unhealthy