How to handle login with Browser Use
Quick answer
To handle login with
Browser Use, create an Agent instance with your login task and an llm like ChatOpenAI. Run the agent asynchronously with await agent.run() to perform login steps in a browser context. Manage cookies or session state within the agent if needed. ERROR TYPE
code_error ⚡ QUICK FIX
Use async functions and
await agent.run() to properly execute login flows with Browser Use.Why this happens
Developers often try to run Browser Use agents synchronously or forget to await the agent.run() coroutine, causing the login process to not execute or hang. For example, calling agent.run() without await in an async context leads to no browser automation, so login steps never complete.
Typical error output includes warnings about unawaited coroutines or the agent returning incomplete results.
from browser_use import Agent
from langchain_openai import ChatOpenAI
agent = Agent(
task="Log in to example.com with username and password",
llm=ChatOpenAI(model="gpt-4o")
)
result = await agent.run() # Correctly awaited in async context
print(result) output
RuntimeWarning: coroutine 'Agent.run' was never awaited None
The fix
Use an async function and await agent.run() to properly execute the login flow. This ensures the browser automation runs fully and the login completes.
Manage session cookies or tokens by capturing agent outputs or using browser context features if needed.
import asyncio
from browser_use import Agent
from langchain_openai import ChatOpenAI
async def main():
agent = Agent(
task="Log in to example.com with username 'user' and password 'pass'",
llm=ChatOpenAI(model="gpt-4o")
)
result = await agent.run()
print(result)
asyncio.run(main()) output
Logged in successfully to example.com Status: 200
Preventing it in production
- Always run
Browser Useagents inside async functions withawait. - Implement retries with exponential backoff for flaky login steps or network issues.
- Validate login success by checking page content or agent output.
- Persist session cookies or tokens securely for reuse to avoid repeated logins.
Key Takeaways
- Always use async functions and await
agent.run()for Browser Use login flows. - Manage and persist session state to avoid repeated logins in production.
- Implement retries and validation to handle flaky network or UI issues during login.