embed

@conciv/embed

The browser bundle that mounts the conciv widget on a host page.

rpc transport

Every widget tab talks to the engine over ONE connection per (tab, apiBase). The browser client factory in @conciv/contract is the only place that picks the transport:

1. At boot (and again after a rebind() to a new engine base) it dials /rpc-ws with a bounded open timeout.
2. If the socket opens, that tab rides the websocket for core rpc AND every extension router (ext.<slug>) for the rest of its life. Mid-session drops never change transport — the reconnecting wrapper re-dials the websocket and ClientRetryPlugin re-issues the calls.
3. If the socket does not open, the tab sticks to fetch/SSE and logs a warning naming the base, so an active fallback is never silent.

There is no connection-error state today: if fetch/SSE also fails, the tab has no dedicated recovery UI (tracked in #350).

No user-agent sniffing is involved anywhere.

ws-blocked networks

Some corporate proxies drop websocket upgrades. Such a tab falls back to fetch/SSE automatically and keeps working, with one accepted regression: browsers cap a single origin at six HTTP connections, so the widget's long-lived streams starve once several tabs are open against the same engine. On the websocket transport that limit does not apply.

To pin a transport explicitly — for a blocked network, or to reproduce the fetch path — set widget.transport:

conciv({widget: {transport: 'fetch'}}) // never probe, always fetch/SSE
conciv({widget: {transport: 'websocket'}}) // never probe, always /rpc-ws

auto (the default) is the boot probe described above.