This is where authorization begins. Connecting takes about five minutes and happens entirely on Intuit's own pages.
Before you start
Sign in to QuickBooks Online as an Admin or Accountant — only those roles can authorize an app
Decide which company to connect. Starting with a test company is recommended
What happens
You're taken to Intuit's authorization screen
You choose the company to connect
You review the exact permissions being requested
You click Connect, and you're returned here
What this app is granted
Read your chart of accounts — so it can only ever propose accounts you already use
Read transactions that need categorizing
Write a category back to a transaction, once you approve it
What it never receives
Your QuickBooks password, your bank login, payment or card details, or payroll data. Authorization happens on Intuit's page, so your credentials are never entered into this system.
After connecting
The agent starts in dry-run mode. It reads your transactions and shows you what it would categorize, but writes nothing to your books until you review the output and switch it on yourself.
Changing your mind
You can revoke access at any time from QuickBooks under Settings → Apps. Revocation is immediate.