Both give an AI agent an inbox it can send from and read replies in, over an API or MCP. AgentMail is an inbox API built for agents. Faivelo is business email hosting where an agent gets the same real mailbox your staff do. That one difference explains most of the rest.
AgentMail started from the agent. An inbox is an API object you create with one call, often one per task or per user, and mail arrives by webhook or websocket. Its free plan gives you 3 inboxes on an agentmail.to address with no domain to set up, which makes it the quickest way to try an idea.
Faivelo started from the business. You add your domain, Faivelo writes the DNS records, and every address on it is a full mailbox with webmail, IMAP and SMTP. An agent gets one of those mailboxes and a key that reaches only it. A person on your team can open the same mailbox on a phone and see exactly what the agent sent and what came back.
What a fleet of agent inboxes costs
AgentMail prices by inbox. Faivelo prices by plan, with unlimited mailboxes on every one. So the gap depends on how many inboxes you run.
| Agent inboxes | AgentMail | Faivelo |
|---|---|---|
| 3, no custom domain | $0 (Free, agentmail.to address) | No free mailbox plan; Growth $12 |
| 10 on your domain | $20 (Developer) | $12 (Growth) |
| 50 on your domain | $200 (Startup) | $12 (Growth) |
| 150 on your domain | $200 (Startup) | $12 (Growth) or $24 (Pro, webhooks) |
Monthly list prices, checked 4 October 2026. AgentMail Startup includes up to 150 inboxes.
Volume is the other half. AgentMail Free includes 3,000 emails a month and Developer 10,000. Faivelo Growth includes 20,000 API sends a month and Pro 50,000. Both warm new senders up, so neither lets a brand new domain send at full speed on day one.
Where AgentMail is the better pick
If you want to try something this afternoon without a domain, AgentMail's free plan is the right call. If your product creates an inbox per end user or per task by the thousand, it is built for that pattern: Faivelo caps an agent key at 10 new mailboxes a day, on purpose, because ours are real mailboxes on your domain. AgentMail also offers websockets for inbound mail, a SOC 2 report on its Startup plan, and EU or self-hosted deployment on Enterprise.
Where Faivelo is the better pick
Pick Faivelo when the agent should act like a member of staff on your own domain. support@ or invoices@ is a mailbox a person can read along in, reply from, or take over, in webmail or any mail app. The price stays flat however many agents you add, and the same plan hosts your team's own email too. The hosted MCP server connects to claude.ai and Claude Code with OAuth, so you tick which mailboxes Claude may use instead of pasting a key, and headless agents can use a scoped agent key. Domain setup is automatic on Cloudflare, Vercel, GoDaddy and most other hosts.
An agent inbox you can also open on your phone is a different thing from an inbox only your code can see.
Give your agents real mailboxes
Add your domain, create an agent key, and connect Claude or your own code. Fourteen days free, no card, with MCP switched on during the trial.