Happy Valley

MachineMail

Email API and MCP server that gives AI agents inboxes of their own

Freemium · $9Team communicationDeveloper tools
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MachineMail is a developer tools tool for Developers and Small businesses, offered as freemium ($9/mo). Popular alternatives include agentmash, Pairon, Whereby.

About MachineMail

MachineMail is an email API for AI agents. It gives each agent a real address on the shared machinemail.dev domain or on your own domain, so it can sign up for services, wait for one-time codes, read replies and answer in thread. Every inbound message arrives with a trust report.

Inboxes are created with one API call or by a catch-all domain, and can be ephemeral or permanent. A hosted MCP server exposes 17 tools, and wait_for_message holds the call open until mail lands. Mail is checked for SPF, DKIM and DMARC, sender history, hidden text, links and attachments, then rated verified, known, unknown, suspicious or quarantined, and hidden text is removed before the agent reads it. Pods, scoped API keys, allow and block lists, drafts for human review, and signed webhooks, SSE and WebSocket events round it out. Inboxes are free on every plan; paid plans raise limits.

It suits developers building agents that must handle email without exposing the model to prompt injection. AgentMail is the closest rival, and MachineMail's /v0 API mirrors its paths, so clients switch by changing the base URL and key. Resend is built for sending product email rather than agent inboxes. MachineMail is new and publishes few company details.

On November 3, 2026 MachineMail launched on Product Hunt and was ranked #7 on Product Hunt's daily leaderboard for that date. An agent can try it with no account through a sandbox inbox that can send 10 messages a day and expires after 24 hours unless a person claims it. Buying tip: paid overage is metered, so watch inbound volume.

Key features of MachineMail

  • Free inboxes on machinemail.dev or your own domains, ephemeral or permanent
  • Trust report and level on every inbound message
  • Agent-safe text with hidden text and zero-width characters removed
  • Hosted MCP server with 17 tools, including wait_for_message
  • Catch-all domains that create an inbox on first delivery
  • Pods and scoped API keys to separate customers or agents
  • Drafts that a person reviews and sends from the dashboard
  • Signed webhooks retried for five days, plus SSE and WebSocket events

Pros and cons

Pros

  • Unlimited inboxes are free on every plan
  • Trust layer addresses prompt injection and phishing in email
  • AgentMail-compatible API makes switching a config change
  • Agents can self-register a sandbox inbox without a human first
  • Spam and quarantined mail are never billed

Cons

  • New service that publishes no team, legal entity or address on its site
  • Free plan caps mail at 100 messages a day
  • No annual pricing listed
  • CLI is still in early access
  • Dedicated Slack support only on the $199 Scale plan

MachineMail pricing

MachineMail uses a freemium model.

PlanPriceIncludes
Free$03,000 messages/mo (100/day), 1 GB, 1 custom domain, 1 seat
Pro$9 / mo7,500 inbound, 2,500 outbound, 10 GB, 10 domains, unlimited seats
Team$49 / mo45,000 inbound, 15,000 outbound, 30 GB, 50 domains, unlimited seats
Scale$199 / mo200,000 inbound, 65,000 outbound, 150 GB, 250 domains, Slack support

Source: machinemail.dev · checked on Nov 4, 2026

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How MachineMail compares in Developer tools

Rank by votes
#2 / 91

0 votes from members

Starting price
$9

55% below the category median ($20/mo)

Free alternatives
23

Free or open-source tools in Developer tools

MachineMail ranks #2 of 91 developer tools tools by community votes and is priced below most tools in the category.

Common use cases

  1. 1Letting an agent sign up for a service and read the verification code
  2. 2Giving each customer of a multi-tenant agent app a separate pod
  3. 3Triaging inbound support or sales email with trust-based rules
  4. 4Running QA tests that need throwaway inboxes
  5. 5Having an agent draft replies that a person approves before sending

Best for

Developers building AI agents that need their own email addresses and a safe way to read untrusted inbound mail.

Not ideal for

Teams that only need to send transactional or marketing email from an app (Resend).

Integrations

  • Claude Code
  • Codex
  • OpenCode
  • GitHub Copilot
  • ChatGPT
  • VS Code
  • Zed
  • Goose

Our take

MachineMail is a focused, well-documented choice for agent email, and the trust layer is its strongest point. Start on the free plan, and treat it as a young vendor until it publishes more about the company behind it.

FAQ

What is MachineMail?
MachineMail is a Developer tools tool: Email API and MCP server that gives AI agents inboxes of their own.
How much does MachineMail cost?
MachineMail uses a Freemium model; paid plans start at $9 per month.
What are the best alternatives to MachineMail?
Community-listed alternatives to MachineMail include agentmash, Pairon, Whereby, BAND.
What does MachineMail integrate with?
MachineMail integrates with Claude Code, Codex, OpenCode, GitHub Copilot, ChatGPT, VS Code and more.
Which platforms does MachineMail support?
MachineMail is available on web.
Who is MachineMail for?
Developers building AI agents that need their own email addresses and a safe way to read untrusted inbound mail.

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