subscriptions

subscriptions/listen change-notification streams (protocol revision 2026-07-28). The server publishes tools/list_changed; the client receives it both via the auto-opened stream (ClientOptions.listChanged, the same option a 2025-era client sets) and a manual client.listen() call.

The publish surface differs by entry: over HTTP (createMcpHandler) the example calls handler.notify.toolsChanged() on the cross-request ServerEventBus; over stdio (serveStdio) it toggles a RegisteredTool on the pinned instance, whose tools/list_changed the entry's listen router fans onto every open subscription.

# stdio (the client spawns the server itself):
pnpm tsx examples/subscriptions/client.ts

# Streamable HTTP (two terminals):
pnpm tsx examples/subscriptions/server.ts --http --port 3000
pnpm tsx examples/subscriptions/client.ts --http http://127.0.0.1:3000/

Source: examples/subscriptions/README.md