🤖 Robots start here
mailhles BETA

a hole in the cloud you throw mail into

Let your AI agent get past the email verification step.

A mailhole is a private disposable inbox your agent spins up and reads over MCP — so automated signups, magic links, OTP codes, and password resets just work. No human in the loop, no Gmail API, no scraping. Simple, reliable, and cheap.

Start 7-day free trial See pricing

$9.99/year after · cancel in one click · we'll let you know before the trial ends

Works with any MCP client
Claude CodeCodexCursorVS CodeWindsurf
> Test the new user acquisition flow ✻ Thinking… ● I'll register a real account using a throwaway inbox. ✻ Discombobulating… ● create_address(mailholes) ⎿ salty-cape-q3@mailholes.com → submitted signup form ✻ Waiting for email… (1s) (2s) (3s) (4s) ● get_message(mailholes) ⎿ rendered message From no-reply@MyAmazingNewApp.com Subject Verify your email Your code: ABCD1234 ● Entered ABCD1234 · signed in ✓ ✻ Running the rest of the tests… ● ✓ All tests passed · 6/6 acceptance checks > Test the new user acquisition flow ⏎ send · esc to interrupt
🤖Agent-firstNative MCP. No integration code to write.
🔒PrivateIsolated per key, mail never leaves our servers.
🚫Ad-freeNo ads or popups to derail your agent.
$9.99/yrless than $1 a month
25live mailholes at once
~5sto read a verification email

How it works

👤 What humans do once, then step away

  1. Start your free trial and generate an API key.
  2. Add mailholes as an MCP server in your agent (Claude Code, Codex, Cursor, VS Code, Windsurf, or any MCP client) using that key.
  3. That's it. Hand the rest to your agent.

Run in your terminal. Drop --scope user to add it for the current project only.

claude mcp add --transport http --scope user mailholes \
  https://mailholes.com/mcp \
  --header "Authorization: Bearer YOUR_API_KEY"

🤖 What agents do every run

  1. Create a mailhole: call create_address → a readable mailhole like calm-fox-7k@mailholes.com (up to 25 live).
  2. Use it in the flow: sign it up, request a code, trigger a magic link. Mail is captured and parsed automatically.
  3. Read it over MCP: list_messages → get_message (or search_messages) and pull the code from the body.
  4. Clean up: delete_address when done, or just let it auto-expire (~1 hour).

Housekeeping: agents can also call list_addresses to see what's live, account_status to check quota and renewal, and clear_all to wipe every mailhole at once (needs confirm: true).

Every key is isolated to its own account, so only you can read your mail. Your mailholes and their messages never leave our servers, and the whole inbox self-cleans on a ~1-hour timer.

How it compares

11–108× cheaper than testing-email APIs100% less hassle than traditional disposable inboxes

 Public temp-mailTesting-email APIs
Agent-readableScraping / variesREST API · some MCPNative MCP
PrivatePublicYesIsolated per key
Ad-freeAds & pop-upsNoneNone
DeliverableOften blockedReal domainReal domain
Time to set upInstant (no API)Minutes (code)Seconds · paste MCP
Price, per yearFree (ad-supported)$108–1,080 / yr$9.99 / yr

Testing-email APIs = Mailosaur, MailSlurp, testmail.app, Mailsac, MailSink and similar.

Want a full-featured QA suite (SMS, SDKs, deep assertions)? Go with Mailosaur or MailSlurp. Just want a throwaway inbox your agent can read, for $9.99 a year? Now you're thinking with mailholes.

Pricing

$9.99/year

7-day free trial first · less than $1 a month

  • Up to 25 active mailholes
  • MCP + HTTP access
  • ~1 hour message retention
Start free trial
Why we charge a little, on purpose. Disposable email is catnip for fraud and spam, which is exactly why free temp-mail services are blocked everywhere and full of junk. A small annual fee ties every inbox to a real, chargeable identity. That single fact keeps the network clean, keeps our domains trusted by the sites you sign up to, and means we never have to sell your data to pay the bills. The price is the feature.

Questions

What's a mailhole?

One disposable email inbox. Your agent creates it with a single MCP call, gets a real address like calm-fox-7k@mailholes.com, and reads any mail sent to it. You can have up to 25 live at once.

Do I need a credit card for the free trial?

Yes — the trial requires a card so every account ties to a real, chargeable identity (that's what keeps the network clean and our domains trusted). You won't be charged during the 7 days, we'll let you know before it ends, and you can cancel in one click. After that it's $9.99/year.

Why is messages retention only ~1 hour?

One hour is plenty for automated flows — verification mail usually arrives in seconds. Short retention is deliberate: throwaway inboxes shouldn't pile up mail, and auto-wiping keeps your data from lingering on our servers.

Can my agent send email too?

No — mailholes is receive-only by design. It captures and parses incoming mail (codes, links, confirmations) for your agent to read. It is not an SMTP relay, which is also what keeps it off spam blocklists.

How is it private?

Every API key is isolated to its own account, so you can only ever read your own mail. Messages never leave our servers, are never sold or used for ads, and auto-delete after about an hour.

What if I need more than 25 inboxes or longer retention?

The $9.99/year plan covers 25 live mailholes — and since each one frees its slot when you delete it or it expires, that's a lot of throughput. (During the free trial, creation is capped at 25 mailholes total; the delete-and-reuse throughput kicks in once you subscribe.) Need more? Email support@mailholes.com and tell us about your use case.