gmail-multi-mcp
Connects AI to several Google accounts at once: mail, files, calendar and contacts.
The problem
The connectors that ship with AI assistants handle one account. When work lives in one address, invoices arrive at another and personal mail at a third, there is no way to ask anything that spans two of them: you switch connectors and ask again.
Why it exists
We needed it ourselves. The account becomes just another field on each query, and when you leave it out the question goes to every mailbox at once and the answers come back as a single list, sorted by date. If one account's permission has expired, the others still answer and the failure is reported rather than hidden.
What you can do with it
MIT licensed: usable in any project, commercial included, with no permission and no fee. Consent happens on Google's own screen, and credentials never leave the machine it is installed on.