Agent Mailbox
An agent mailbox is a real, persistent email inbox that an AI agent owns and operates - it can send messages, receive and read inbound mail, and is addressed and controlled entirely through an API or an MCP server with a scoped key. Unlike a borrowed human account or a send-only API, an agent mailbox is provisioned for the agent itself and is two-way by design.
Last updated June 30, 2026
How it differs from a borrowed account
A borrowed account is a human's existing inbox the agent has been handed credentials to - fragile, often blocked by OAuth and CASA audits, and not really the agent's own. An agent mailbox is minted for the agent: it owns the address, holds its own messages, and is reached over a clean API rather than by screen-scraping webmail.
Send and receive
An agent mailbox is two-way. The agent can send (e.g. POST /api/v1/mailboxes/{id}/outbound) and read back what arrives - replies, confirmations, one-time codes - by listing the inbox (GET …/messages?direction=inbound). A send-only API gives the agent no inbox to read; an agent mailbox does.
Scoped access
Each mailbox is reached with a scoped key (read or read_write) usable as a Bearer token on both REST and the native MCP server. Keys can carry an expiry, and a read-scoped key cannot send - so an agent is granted exactly the access it needs.
In Sairaph Mail
In Sairaph Mail, an agent mailbox is EU-resident by default, encrypted at rest with a dedicated per-customer key, and callable over both REST and a native MCP server.
Related: Email for AI agents - the 2026 guide · Product.
Related
Give your agent a real mailbox
Two-way email over REST and a native MCP server, EU-resident by default.
EU data residencyPer-customer encryptionNative MCP