## Direct WebSocket CDP providers

Some hosted browser services expose a **direct WebSocket** endpoint rather than

the standard HTTP-based CDP discovery (`/json/version`). OpenClaw supports both:

- **HTTP(S) endpoints** — OpenClaw calls `/json/version` to discover the

WebSocket debugger URL, then connects.

- **WebSocket endpoints** (`ws://` / `wss://`) — OpenClaw connects directly,

skipping `/json/version`. Use this for services like

[Browserless](https://browserless.io),

[Browserbase](https://www.browserbase.com), or any provider that hands you a

WebSocket URL.

the standard HTTP-based CDP discovery (`/json/version`). OpenClaw accepts three

CDP URL shapes and picks the right connection strategy automatically:

- **HTTP(S) discovery** — `http://host[:port]` or `https://host[:port]`.

OpenClaw calls `/json/version` to discover the WebSocket debugger URL, then

connects. No WebSocket fallback.

- **Direct WebSocket endpoints** — `ws://host[:port]/devtools/<kind>/<id>` or

`wss://...` with a `/devtools/browser|page|worker|shared_worker|service_worker/<id>`

path. OpenClaw connects directly via a WebSocket handshake and skips

`/json/version` entirely.

- **Bare WebSocket roots** — `ws://host[:port]` or `wss://host[:port]` with no

`/devtools/...` path (e.g. [Browserless](https://browserless.io),

[Browserbase](https://www.browserbase.com)). OpenClaw tries HTTP

`/json/version` discovery first (normalising the scheme to `http`/`https`);

if discovery returns a `webSocketDebuggerUrl` it is used, otherwise OpenClaw

falls back to a direct WebSocket handshake at the bare root. This covers

both Chrome-style remote debug ports and WebSocket-only providers.

Plain `ws://host:port` / `wss://host:port` without a `/devtools/...` path

pointed at a local Chrome instance is supported via the discovery-first

fallback — Chrome only accepts WebSocket upgrades on the specific per-browser

or per-target path returned by `/json/version`, so a bare-root handshake alone

would fail.

### Browserbase