Optional, but worth doing. It's what lets your System update a single cell in your checklists instead of creating a new file every time something changes. Takes about five minutes.
Without Zapier, your System can still read and create checklists, it just can't edit one cell in place. Every small update (a status change, a new date) means generating a new file, and those pile up in your Drive over time. Connecting Zapier fixes that: your System can update a cell directly, the same file stays current the whole way through a transaction.
Go to zapier.com and sign up if you don't already have an account. Use the same Google account you use for Drive and Gmail, it keeps things simple later.
In Cowork, go to Customize → Connectors. Find Zapier in the list and click Connect, then sign in with the Zapier account you just created.
You don't need to configure anything inside Zapier's own dashboard by hand. The first time your System needs to edit a checklist cell in place, it'll ask you to approve turning on that one Google Sheets action, one click, and it's done for good.
Don't see Zapier in the connector list? Make sure you're in Customize → Connectors, not the Plugins tab, those are two different pages. If Claude says it can't find a Google Sheets action to enable, tell it directly: "connect Zapier's Google Sheets update-row action" and it'll walk you through the approval. Still stuck? Email hello@chatelainekey.com.