Browser-Use (Web Automation)

The sandbox image ships browser-use (installed in /home/user/.venv) and a full chromium build (playwright). This skill drives them: write a short Python script with Agent(task=..., llm=..., browser=...), run it, report the result.

When to use

• Multi-step web tasks: search → open → extract → compare → download
• Form filling / login flows / clicking through pages
• Structured extraction (tables, listings, prices) that a single fetch can't parse
• Screenshots / visual confirmation of a page state
• Anything needing JS-rendered content (SPA pages the fetch tools miss)

For a single plain fetch, prefer the existing web tools (lighter). Reach for browser-use when they come back empty or the task is interactive.

How to run

# chromium executable (version dir may change — resolve dynamically):
CHROME="$(find /home/user/.cache/ms-playwright -name chrome -type f | head -1)"

# LLM = our gateway (OpenAI-compatible). PRISMER_BASE_URL / PRISMER_API_KEY
# are already in the environment; never hardcode them in the script.
cat > /tmp/bu_task.py <<'PY'
import os, asyncio
from browser_use import Agent, ChatOpenAI, Browser

async def main():
    llm = ChatOpenAI(
        base_url=f"{os.environ['PRISMER_BASE_URL']}/api/v1",
        api_key=os.environ['PRISMER_API_KEY'],
        model=os.environ.get('PRISMER_MODEL', 'deepseek-v4-flash'),
        temperature=0.0,
        # REQUIRED for the Prismer gateway: browser-use defaults to forcing
        # JSON-schema structured output (response_format=json_schema) which
        # our upstream models reject with 400 "response_format type
        # unavailable" (verified 2026-08-07). Disable it; the agent still
        # extracts via its normal flow.
        dont_force_structured_output=True,
    )
    browser = Browser(
        headless=True,
        executable_path=os.environ['CHROME'],
    )
    agent = Agent(
        task="<TASK>",  # be specific: steps, URLs, what to extract, output format
        llm=llm,
        browser=browser,
    )
    history = await agent.run(max_steps=30)
    print("RESULT:", history.final_result())
    print("URLS:", history.urls())
    print("ERRORS:", history.errors())
    await browser.close()

asyncio.run(main())
PY
CHROME="$CHROME" /home/user/.venv/bin/python /tmp/bu_task.py
rm -f /tmp/bu_task.py

Task-writing rules (from browser-use docs)

• Be specific: "Go to https://…, use extract with query 'first 3 quotes and their authors', save to quotes.csv via write_file" — open-ended tasks fail.
• Name actions: "use search action for …", "use click to open first result in a new tab", "use send_keys with 'Tab Tab Enter'" — the agent maps these to its built-in tools.
• Error recovery: if navigation is blocked, fall back to a search engine; if a click fails, use keyboard navigation (send_keys).
• max_steps: default 100; keep 30 for focused tasks, raise for long flows.
• Anti-bot: if a page blocks automation, try use_cloud=True — NOT available here (no Browser-Use Cloud key). Fall back to search/cache.

Environment facts

Output contract

Report to the user: history.final_result() (the extracted answer), the URLs visited, and any errors. If history.is_successful() is False, say so plainly with history.errors() — do not invent a completion. Attach screenshots (history.screenshot_paths()) as task assets when they matter.