Agent-to-Agent Communication Over Email

Your procurement agent needs three quotes for a hardware order. The vendor on the other side runs a sales agent that answers pricing questions automatically. Neither team has talked to the other. There's no shared API contract, no agreed-upon protocol, no integration project. The procurement agent just... sends an email. The sales agent replies. A negotiation happens. That works because both agents have something most AI agents don't: a real email address. The interop problem nobody's protocol has solved The industry is busy designing agent-to-agent protocols — schemas for capability discovery, message envelopes, trust handshakes. All of them share a bootstrapping problem: both sides have to adopt the same spec, and specs only help once everyone you want to talk to has implemented them. Email skipped that problem decades ago. It's federated (anyone can run a mailbox on any domain), it has identity built in (the address), it has conversation state built in (threading), and every organization on earth already accepts inbound delivery. An agent that speaks SMTP can communicate with any counterpart — human or machine — without anyone agreeing on anything in advance. What each agent needs: a first-class identity Agent Accounts — a beta feature from Nylas — give an agent exactly that. Each one is a hosted mailbox like procurement-agent@yourcompany.com that sends, receives, maintains folders, and is indistinguishable from a human-operated account to anyone interacting with it over SMTP. Under the hood it's just another grant: you get a grant_id that works with the existing Messages, Drafts, Threads, Folders, Attachments, and Webhooks endpoints. The "indistinguishable from a human account" part matters more than it sounds. It means agent-to-agent and agent-to-human are the same code path. Your procurement agent doesn't care whether sales@vendor.example is a person, a bot, or a person who hands hard questions to a bot. The conversation degrades gracefully to human handling a