Browser Use Version

0.13.10 and main at 302d8fc

Bug Description, Steps to Reproduce, Screenshots

When an action or a step fails with an exception that has no message, such as TimeoutError(), ConnectionError() or a failed bare assert, browser-use formats it with str(e), which is empty:

• navigate logs ❌ Navigation failed: and returns ActionResult(error='Navigation failed: ') (tools/service.py#L555-L558, #L581); search does the same (#L498-L500).
• AgentError.format_error returns '' (agent/views.py#L966, #L980-L982), so _handle_step_error logs ❌ Result failed 1/6 times: with nothing after the colon and puts an empty error into the next prompt.

Neither the log nor the model gets the exception type. I see these empty lines in a production app. session.py already logs the type for the same navigation failure (Navigation failed: {type(e).__name__}: {e}, session.py#L1005); the action and the agent do not.

Repro: format_error directly, then navigate on headless Chromium with _navigate_and_wait replaced by a function that raises ConnectionError().

Failing Python Code

import asyncio
from importlib.metadata import version

from browser_use.agent.views import AgentError
from browser_use.browser import BrowserProfile, BrowserSession
from browser_use.tools.service import Tools


async def drop_connection(*args, **kwargs):
	raise ConnectionError()  # stands in for any failure raised without a message


async def main() -> None:
	print('browser-use', version('browser-use'))
	for error in (TimeoutError(), ConnectionError(), AssertionError()):
		print(f'AgentError.format_error({type(error).__name__}()) = {AgentError.format_error(error)!r}')

	session = BrowserSession(browser_profile=BrowserProfile(headless=True, user_data_dir=None, enable_default_extensions=False))
	await session.start()
	BrowserSession._navigate_and_wait = drop_connection
	result = await Tools().navigate(url='http://127.0.0.1:9/', new_tab=False, browser_session=session)
	print('navigate ActionResult.error =', repr(result.error))
	await session.kill()


asyncio.run(main())

LLM Model

None (no agent or LLM involved)

Operating System & Browser Versions

macOS, Python 3.11, Playwright Chromium (headless)

Full DEBUG Log Output

browser-use 0.13.10
AgentError.format_error(TimeoutError()) = ''
AgentError.format_error(ConnectionError()) = ''
AgentError.format_error(AssertionError()) = ''
ERROR    [BrowserSession] ❌ Navigation failed: 
navigate ActionResult.error = 'Navigation failed: '

Expected: the exception type when the message is empty, e.g. Navigation failed: ConnectionError and TimeoutError from format_error.

Fix: str(e) or type(e).__name__ in those places. PR follows.