> ## Documentation Index
> Fetch the complete documentation index at: https://browseruse-0aece648-magnus-streaming-api-link.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# FAQ

> Common questions and solutions.

## How much does a task cost?

Set `max_cost_usd` to cap spending per task. Default is $20. A typical task costs $0.01–\$0.05. Check `result.total_cost_usd` after each task.

## Which model should I use?

* **bu-mini** (default) — faster, cheaper. Good for most tasks.
* **bu-max** — more capable. Use for complex multi-step workflows.

## How do I get the live browser URL?

`live_url` is not available immediately on session creation. Poll `sessions.get()` until it appears (\~3-5 seconds).

```python theme={null}
import asyncio
session = await client.sessions.create(task="Go to example.com")
while True:
    s = await client.sessions.get(str(session.id))
    if s.live_url:
        print(s.live_url)
        break
    await asyncio.sleep(0.5)
```

## How do I authenticate on websites?

1. **Profiles** — sync your local browser cookies: `curl -fsSL https://browser-use.com/profile.sh | sh`. See [Profiles](/cloud/guides/authentication).
2. **1Password** — auto-fill passwords and 2FA codes. See [1Password & 2FA](/cloud/guides/1password) (v2 SDK).
3. **Secrets** — pass credentials scoped by domain. See [Secrets](/cloud/guides/secrets) (v2 SDK).

## Task failed or wrong output

* **Add a start URL.** Don't make the agent search — send it directly.
* **Simplify instructions.** Break complex tasks into smaller follow-up tasks in the same session.
* **Check the live URL.** Watch what the agent does in real time.
* **Try bu-max.** More capable model for harder tasks.

## Getting blocked by a website

Stealth is on by default. If still blocked:

* **Try a different proxy country** to match the target region.
* **Use a profile** with logged-in cookies to bypass login walls.

## Rate limited (429 errors)

The SDK auto-retries 429 responses with exponential backoff. If persistent, you may need more concurrent sessions — contact support.

## How do I save files from a task?

Use workspaces. See [Workspaces & files](/cloud/agent/workspaces).

```python theme={null}
workspace = await client.workspaces.create(name="my-workspace")
result = await client.run("Save top 3 HN posts as posts.json", workspace_id=str(workspace.id))
files = await client.workspaces.files(str(workspace.id), include_urls=True)
```

## How do I use Browser Use as a sub-agent?

Use `client.run()` inside your agent's tool function. For a full working example with streaming and live preview, see the [Chat UI tutorial](/cloud/tutorials/chat-ui).

## v2 vs v3 — which should I use?

Use v3 (`from browser_use_sdk.v3 import AsyncBrowserUse`). It has sessions, workspaces, live messages, and recording. v2 is legacy — only use it if you need `secrets`, `allowed_domains`, or `op_vault_id`.