Most "AI agent that emails for you" demos point a language model at a human's Gmail inbox over OAuth. That works until the agent needs its own identity: an address people reply to, a calendar that accepts invites, a mailbox your application owns end to end. Borrowing a human's inbox means inheriting their OAuth scopes, their rate limits, and the awkwardness of an agent sending mail as a person who didn't write it.

A Nylas Agent Account flips that around. It's a real name@yourcompany.com mailbox that you create and control entirely through the API — it sends, receives, hosts calendar events, and RSVPs, and it's indistinguishable from a human-operated account to anyone on the other end. Under the hood it's just a grant, so the grant_id you get back works with the same grant-scoped endpoints — Messages, Threads, Folders, Drafts, Attachments, Contacts, Calendars, and Events — you've already used for connected accounts, plus the standard webhook triggers.

This post is a working tour of provisioning one, from two angles: the HTTP API for your backend, and the Nylas CLI for the terminal and quick experiments. I work on the CLI, so the terminal commands below are the exact ones I reach for.

Why an Agent Account beats borrowing a human inbox