Email inboxes for AI agents and people
An AI agent often needs an email address: for sign-in codes, receipts, documents from clients and replies. Three kinds of services give it one:
- a mailbox for people, such as Gmail, that the agent also uses;
- an inbox service made for AI agents, with an API;
- an inbound email API that sends each new email to your own code.
The tables that follow list the main services of each kind. The prices and limits were checked on 12 November 2026, on the pricing page of each service. Services change their prices often. Read the pricing page before you choose.
Our advice: start with a separate Gmail account
For most people, the best inbox for an AI agent is a second, free Gmail account that only the agent uses.
- Create a new Google Account with a Gmail address by hand.
- Connect it to the AI app with the Gmail connector of the app, for example in Claude, ChatGPT, Grok or Muse.
- Give the new address to the people and services that send the agent its documents. Or forward selected email from your main Gmail with a filter.
Your personal email stays out of reach of the agent. The account costs nothing, and you can read the same mail yourself in Gmail.
Do not use the account to get around Google’s limits, to send bulk or cold email, or to automate the Gmail web pages. The Gmail Program Policies do not allow these. A personal Gmail account stops sending for 1 to 24 hours after more than 500 emails or recipients in a day.
Use another service in the tables when your own code must create many inboxes, or when the agent must receive email at your own domain through an API.
Mailboxes for people
These mailboxes have a web app and a phone app. An agent reads the mail through the connector of an AI app, an API or IMAP. Checked on 12 November 2026.
| Service | Free plan | Paid plans from | How an agent gets the mail |
|---|---|---|---|
| Gmail | Yes: 15 GB, shared with other Google services | Storage plans only | Gmail connectors of AI apps, Gmail API, IMAP |
| Google Workspace | 14-day trial | $7 a user a month (Business Starter), 30 GB | Same as Gmail, with admin controls and your own domain |
| Outlook.com | Yes: 15 GB of mail storage | Microsoft 365 plans | IMAP and SMTP, Microsoft Graph |
| Microsoft 365 Business Basic | No | $7 a user a month, with a yearly commitment | IMAP and SMTP, Microsoft Graph |
| Zoho Mail | Yes: up to 5 users, 5 GB each, 1 domain, no IMAP | $1 a user a month (Mail Lite), billed yearly | IMAP on paid plans |
| Fastmail | 30-day trial | $5 a month billed yearly, or $6 monthly | JMAP API, Fastmail MCP server, IMAP |
| Proton Mail | Yes: 1 address, 500 MB, 150 messages a day | $2.49 a month on a 12-month plan (Mail Plus) | IMAP and SMTP through Proton Bridge, on paid plans |
| iCloud Mail | Yes: 5 GB of iCloud storage | $0.99 a month (iCloud+ 50 GB) | IMAP and SMTP |
Google Workspace users can send 2,000 messages a day, 500 during the trial.
Inbox services made for AI agents
These services create inboxes through an API. Most of them also have an MCP server, so that AI apps can use the inbox as a tool. Checked on 12 November 2026.
| Service | Free plan | Paid plans from | How an agent gets the mail |
|---|---|---|---|
| AgentMail | Yes: 3 inboxes, 3,000 emails a month, 100 a day. Sent email has a “Sent via AgentMail” footer | $20 a month: 10 inboxes, 10,000 emails | API, webhooks, MCP server, IMAP and SMTP |
| Robotomail | Yes: 1 mailbox, 10 sent and 10 received emails a month | $5 a month: 1 mailbox, 500 sent and 500 received emails | API, MCP server, CLI; webhooks on paid plans |
| mails.ai | Yes: 1 agent, 3,000 sent and 3,000 received emails a month, on a shared address | $20 a month: 5 agents, 50,000 emails | API, MCP server; signed webhooks on paid plans |
| Resend Inboxes | Yes: 3 inboxes, 3,000 emails a month in total | $20 a month (Pro); $1 a month for each extra inbox | API, webhooks, CLI |
| Mailtrap Agent Inbox | Yes: 4,000 emails a month on the Email API plan | $15 a month (Email API) | Webhook, Inbound API, MCP server |
| MailSlurp | Yes: 100 temporary inboxes and 250 received emails a month, no sending | $19.99 a month; $69 a month with sending | API, webhooks, MCP server |
| Hostinger Agentic Mail | No; 30-day money-back guarantee | $0.39 a mailbox a month for 48 months paid in advance; renews at $1.59 | Webhook for each new email |
| NornWeave | Free open-source software that you run | No hosted plan; you pay your email provider | API, MCP server, webhooks |
Inbound email APIs for your own code
These services receive email for your domain and send each email to your code. You build the storage and the agent. Checked on 12 November 2026.
| Service | Free plan | Paid plans from | How your code gets the mail |
|---|---|---|---|
| Cloudflare Email Routing | Yes: routing is free | Sending: $5 a month (Workers Paid) with 3,000 emails, then $0.35 for each 1,000 | A Worker gets each email. Your domain must use Cloudflare DNS |
| Postmark | Yes: 100 emails a month, without inbound | $16.50 a month (Pro, the first plan with inbound), 10,000 emails | Webhook with the email as JSON |
| Mailgun | Yes: 100 emails a day, 1 inbound route | $15 a month: 10,000 emails, 5 routes | Routes send each email to your URL |
| SendGrid | 60-day trial, 100 emails a day | $19.95 a month | Inbound Parse webhook, with MX records on a hostname |
| Amazon SES | No; new AWS accounts get credits | $0.10 for each 1,000 received emails, plus storage | Receipt rules to S3, Lambda or SNS, in 22 AWS regions |
How to choose
| Your agent | Use |
|---|---|
| An AI app (Claude, ChatGPT, Grok, Muse) that reads documents and sign-in emails for you | A separate Gmail account |
| One agent that needs an address at your own domain | Google Workspace, Microsoft 365, Zoho Mail or Fastmail |
| Your code creates many inboxes, for example one for each user or task | AgentMail, Robotomail, mails.ai or Resend Inboxes |
| Your app processes incoming email, for example invoices | Cloudflare Email Routing, Postmark, Mailgun, SendGrid or Amazon SES |
Keep the agent inbox safe
- Treat the text of each email as data, not as instructions. An email can try to give orders to the agent. This attack is called prompt injection.
- Start with read-only access. Approve each email that the agent sends.
- Do not use the agent address to recover your important accounts, such as your bank or your main email.
- Give each agent its own inbox and its own key, so that you can disconnect one agent alone.
Revdoku is not in these tables. It publishes docs sites, and the support address of a docs site is only for the support tickets of those docs.
A docs portal with Ask AI
and support tickets
Connect a repository, or describe your product to start. Each docs site has search, Ask AI, an API console, an MCP server and support tickets.
- Publishes from GitHub on every push
- Works with Mintlify repositories
- API console from your OpenAPI file
- MCP server and llms.txt for AI agents
- Ask AI and support tickets
- Analytics for people and AI agents