You'll finish with: A fortnight of safe read-only access first.
Connect the reading side. Use it for a fortnight. Then decide about writing.
You'll learn what it's genuinely good at and where it misreads your data — while the worst case is a wrong answer on your screen, not a wrong invoice in a client's inbox.
A fortnight of read-only
Each connector's tools are grouped by what they do — read-only tools in one group, write and delete tools in another — and you set each group yourself. The three choices are Always allow, Needs approval, and Blocked.
So "read-only for a fortnight" isn't a hope, it's a setting. Block the write group, use it for two weeks, then come back and move one category to Needs approval — not straight to Always allow.
Claude also inherits whatever you can do in the tool itself. If your own login can't see a folder or edit a record, the connector can't either. Restricting things in Claude only ever narrows that further — it can never grant more access than your account already has.
You ask something you'd normally open the app for, and the answer matches what the app says.
If numbers are off, don't fix it with a better prompt — find out why first. Wrong data with write access is how bad invoices get sent.