> ## Documentation Index
> Fetch the complete documentation index at: https://docs.webrayn.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Browser Sessions

> Session lifecycle in webrain — create, attach a profile, drive with real Chrome, preserve across calls. How sessions carry authentication and why they are execution state.

# Browser Sessions

A **session** is a live browser instance plus its CDP connection, bound to a
profile. In MCP, `webrain_session(op=open, cdp_url=...)` creates a named session
pool that later tool calls route to via `session_id`.

## Lifecycle

```
CREATE → PROFILE ATTACHED → REAL CHROME → SESSION ACTIVE
       → NAVIGATE → PAGE STATE → HANDLE → EXTRACT → VERIFY → PRESERVE
```

Keep the session open across pages; close it with `webrain_session(op=close)`.

## Reuse and re-attach

* Keep a session open for subsequent navigations — never restart a working browser.
* Re-attach an already-authenticated Chrome by pointing `cdp_url`/`CDP_URL` at
  its port; the session and cookies are shared.
* Sessions are isolated: different sessions/browsers have separate cookie jars.
  Set cookies and batch on the SAME connection, or the isolation bites you
  (obscura keeps per-connection cookie jars).

## Sessions and profiles

Sessions bind to profiles (see [Browser Profiles](/concepts/profiles)). The
profile is the durable state; the session is the live instance.