@lensmcp/client-runtime

The browser-side capture layer for LensMCP. It connects to the @lensmcp/bridge WebSocket and streams one envelope per observed event — window.onerror / unhandledrejection, console.*, fetch timing, and History API route changes — plus a window.__LENSMCP_PUBLISH__ hook that in-page instrumentation (@lensmcp/react-instrumentation, @lensmcp/valtio-instrumentation) rides.

It is strictly passive: it never mutates app state, swallows errors, or changes scheduling.

No-build install

For any host without a LensMCP build plugin — webpack, Next.js, or no bundler at all — import the side-effecting entry at your app's top level:

import '@lensmcp/client-runtime/auto';

It resolves the bridge WebSocket endpoint at runtime, so nothing needs to bake the URL in at build time. Resolution order:

1. globalThis.__LENSMCP_WS_URL__ — a full ws://… URL
2. <meta name="lensmcp-ws" content="ws://…">
3. ws://<host>:<port> from __LENSMCP_WS_HOST__ / <meta name="lensmcp-ws-host"> / location.hostname and __LENSMCP_WS_PORT__ / <meta name="lensmcp-ws-port"> / the default port (5747)

Run the bridge alongside your dev server:

lensmcp bridge            # ws://127.0.0.1:5747, forwards to .lensmcp/events.jsonl

For explicit control, call the installer yourself instead of importing /auto:

import { installLensmcp } from '@lensmcp/client-runtime';

installLensmcp({ wsUrl: 'ws://127.0.0.1:5747' });

With a build plugin

When @lensmcp/vite-plugin (or another LensMCP host adapter) is active it injects an equivalent runtime for you with the bridge port already wired — you don't import anything.