每个座席一个ID和邮箱
An email address is an agent's first visible identity handle. Most offerings today are either developer-first or human-first, while agentbox.id is AI-first. It gives each agent a dedicated mailbox — IMAP/SMTP only, no webmail, no API, inbound restricted to the registered human. Free, one per person. Starting with the simplest artifact toward a broader agent identity layer.