Google Verification Process for Unpublished Apps

When developing scripts using Google APIs, you may attempt to access Google Sheets data and encounter the error:
"Access blocked: <project-name> has not completed the Google verification process".

This occurs because your application's OAuth consent screen requires configuration to allow testing—even when only you (the developer) need access.

Fixing Access for Developers and Test Users

Required Action

Complete these steps in your Google Cloud Console before running your script.

Step 1: Navigate to OAuth Consent Screen

1. Go to APIs & Services → OAuth consent screen
   (Location: Left sidebar menu in Google Cloud Console)

Step 2: Add Test Users

1. In the Audience section (labeled Editing app name at the top), find Test users
2. Click Add users
3. Enter your Google account email (and any other test users)
   
4. Click Save

Step 3: Retry Authentication

1. Relaunch your script
2. Complete the OAuth flow when prompted in your browser

Why This Works

Adding test users explicitly grants access to your prototype application, bypassing Google's verification requirement during development. Your credentials will now function locally.

Limitations and Publishing Requirements

If you need to share the app beyond 100 test users or open access publicly:

1. Return to OAuth consent screen → Audience
2. Under App status, click Publish App
   
3. Complete these mandatory fields during publishing:
   • Privacy policy URL
   • Terms of service URL
   • Application description

Publishing Constraints

• Google requires verification for public/dynamic applications (takes ~3-5 days).
• Publishing is unnecessary for:
  • Scripts with ≤100 designated test users
  • Internal tools not requiring public access

For desktop scripts that only you control, adding your email as a test user is the optimal solution.