Authentication Skill

Guide Claude through interactive authentication flows using the browse CLI.

When to Use

Use this skill when:

•A website requires login to access content
•You encounter a login page or authentication wall
•The user needs to authenticate to complete a task
•Session cookies have expired

Prerequisites

Requires the browse CLI and Chrome/Chromium:

bash

browse --version  # Check if installed
bash scripts/setup-browse.sh  # Install if needed

Install manually: pnpm add -g @browserbasehq/browse-cli

Authentication Flow

1. Detect Login Page

After navigating to a URL, check if authentication is needed:

bash

browse snapshot

Look for indicators:

•Form elements with type="password" or type="email"
•Text containing "sign in", "log in", "username", "password"
•OAuth buttons (Google, GitHub, Microsoft, etc.)

2. Prompt User for Credentials

Always ask the user for credentials - never assume or store them.

Example prompt:

code

I've detected a login page. To continue, I'll need your credentials:

1. What is your email/username?
2. What is your password?

Note: Your credentials will only be used to fill the login form and won't be stored.

3. Fill Login Form

Use the snapshot refs to identify form fields:

bash

# Get the current page state
browse snapshot

# Fill the email/username field
browse fill @0-5 "user@example.com"

# Fill the password field  
browse fill @0-8 "their-password"

# Click the submit button
browse click @0-12

4. Handle 2FA/MFA

If a 2FA prompt appears after login:

bash

browse snapshot

Prompt the user:

code

Two-factor authentication is required. Please provide:
- The code from your authenticator app, OR
- The code sent to your phone/email

What is your 2FA code?

Then fill and submit:

bash

browse fill @0-3 "123456"
browse click @0-5

5. Verify Success

After submitting credentials:

bash

browse wait networkidle
browse snapshot

Check for:

•Redirect away from login page
•User profile/avatar elements
•Dashboard or home page content
•Absence of error messages

If login failed:

code

The login attempt was unsuccessful. I see an error message: "[error text]"

Would you like to:
1. Try again with different credentials
2. Use a different login method (OAuth, SSO)
3. Reset your password

OAuth/SSO Flows

For OAuth buttons (Google, GitHub, etc.):

•Click the OAuth button
•A popup or redirect will occur
•User completes authentication in the OAuth provider
•Wait for redirect back to the original site

bash

# Click OAuth button
browse click @0-15

# Wait for OAuth flow to complete
browse wait networkidle

# Verify authentication succeeded
browse snapshot

Common Patterns

Username + Password Form

html

<form>
  <input type="email" name="email">
  <input type="password" name="password">
  <button type="submit">Sign In</button>
</form>

Magic Link / Passwordless

code

I see this site uses passwordless authentication (magic link).

1. Enter your email address
2. Check your email for the login link
3. Let me know when you've clicked the link

What email should I use?

CAPTCHA

code

This login page has a CAPTCHA. I cannot solve CAPTCHAs automatically.

Options:
1. Use `browse session live` to open the browser and solve it manually
2. Try a different authentication method
3. Contact the site administrator

Security Reminders

•Never store or log user credentials
•Credentials are only used to fill form fields
•Recommend users use password managers
•Suggest enabling 2FA when available
•Clear sensitive data from conversation context after use

Troubleshooting

Login button doesn't work

bash

# Try waiting for page to be fully loaded
browse wait networkidle

# Check if button is actually clickable
browse snapshot

# Try clicking by coordinates if ref doesn't work
browse click 450,320

Form fields not found

bash

# Get full snapshot to find correct refs
browse snapshot

# Try using evaluate to find elements
browse eval "document.querySelector('input[type=password]')?.id"

Session expires quickly

•Some sites have short session timeouts
•Consider using browse session create with Browserbase for persistent sessions
•Check if "Remember me" checkbox is available