Choosing email infrastructure for AI agents? Here's how LoftBox compares to AgentMail and RobotoMail on the things that matter when an autonomous agent sends and receives real email: developer access, the Model Context Protocol, standard mail protocols, and—crucially— governance (approval, audit, and data protection).
| Capability | LoftBox | AgentMail | RobotoMail |
|---|---|---|---|
| Send & receive mailboxes | Yes | Yes | Yes |
| Python & TypeScript SDKs | Yes — pip install loftbox, npm i @loftbox/sdk | Yes | CLI only |
| Official MCP server | Yes — npx @loftbox/mcp, with approve/reject tools | Yes | No |
| SMTP submission + IMAP | Yes — mail.loftbox.net :587 / :993 | Yes | No |
| Human-in-the-loop approval | Yes — policy-driven approval gate before send | Basic (draft / allowlist) | No |
| Audit log | Yes — every action recorded | Not documented | Not documented |
| GDPR controls (export / delete-all / retention) | Yes — Art. 20 / 17 / 30 | Not documented | Not documented |
| Web console (GUI) | Yes | API-only | Yes |
| Self-hosted mail delivery | Yes — own MTA | — | — |
| UI languages | 20 | English | English |
| Free tier | Yes — 3 mailboxes, 100 emails/day, 1 custom domain | Yes — 3 inboxes, 100/day | Paid only |
Based on publicly available information as of June 2026. Competitor offerings change—check their current docs.
An AI agent sending email on your behalf is a liability without controls. LoftBox gates outbound mail behind policy-driven approval (a human approves or rejects before anything sends), records every action in an audit log, and ships GDPR controls—data export, delete-all, and retention—out of the box. The same approval gate is exposed through the MCP server, so even agent-driven sending stays under review.
LoftBox runs its own mail transfer agent—DKIM/SPF/DMARC per custom domain—rather than reselling a third-party sending API. You get direct control over deliverability and reputation.
Published SDKs (pip install loftbox, npm i @loftbox/sdk), an official
MCP server (npx @loftbox/mcp) covering the full admin plane, and standard
SMTP submission + IMAP—so existing mail clients and tools connect directly. The
product UI ships in 20 languages.
AgentMail is a mature, well-funded option with a broad SDK lineup; if you only need API-first send/ receive and don't need deep governance or a GUI, it's a solid choice. RobotoMail offers a simple GUI-first experience. LoftBox is the strongest fit when you need oversight, auditability, and data-protection guarantees for agents acting on real email.
LoftBox — API-first email infrastructure for AI agents. Send/receive mailboxes, human-in-the-loop approval, audit logging, GDPR controls, SDKs, MCP, SMTP & IMAP.