Effective 5 September 2026. mailkit is software you download and run on your own Mac. These terms cover that software and this documentation site. They are short on purpose.

​
1. What mailkit is

mailkit is a command-line tool that reads, drafts, organizes, and sends your mail through your own mail account — Gmail, Outlook, Fastmail, or Proton Mail. mailkit is not a mail service. There is no mailkit server, no mailkit account, and no mailkit mailbox. Nothing you do with mailkit passes through our systems. See Privacy.

​
2. Your account with your mail provider

You connect mailkit to a mailbox you already own. You must:
  • have the right to use that mailbox
  • follow your provider’s terms — Google, Microsoft, Fastmail, or Proton
  • keep your Mac and your login Keychain secure
Your provider can suspend or revoke your access at any time under their own rules. We have no control over that and cannot restore it.

​
3. Licence

mailkit is released under the MIT Licence. You may use, copy, modify, and redistribute it under that licence. The licence text ships with the source and governs the software itself. If these terms and the MIT Licence disagree about the software, the MIT Licence wins.

​
4. Acceptable use

Do not use mailkit to:
  • send bulk unsolicited mail, or anything unlawful, deceptive, or harassing
  • access a mailbox you are not authorised to access
  • break your mail provider’s terms or applicable law
You are responsible for every message mailkit sends on your behalf. mailkit requires an explicit --yes before it sends, and the scheduled sweep never sends. Those are safety rails, not a substitute for your judgement.

​
5. Automation and AI agents

mailkit is built to be driven by an AI agent. If you let an agent operate your mailbox, you remain responsible for what it does — including anything it sends, deletes, or discloses. Review the guardrails before you automate anything.

​
6. No warranty

mailkit is provided “as is”, without warranty of any kind, express or implied, including merchantability, fitness for a particular purpose, and non-infringement. We do not warrant that mailkit is error-free, that it will not lose or mis-file a message, or that it will keep working when a provider changes its API. Keep your own backups. Mail moved, trashed, or sent by mailkit may not be recoverable.

​
7. Limitation of liability

To the maximum extent permitted by law, the authors and copyright holders are not liable for any claim, damages, or other liability — including lost mail, lost business, lost data, or any indirect or consequential loss — arising from the software or its use. Because mailkit is free software, our total liability to you is limited to the amount you paid for it.

​
8. Fees

mailkit is free today. If a paid version ever appears, it will be announced before it applies, and it will not change the licence of a version you already have.

​
9. Changes

We may update these terms. The effective date above changes when we do. Continuing to use mailkit after a change means you accept the new terms.

​
10. Governing law

These terms are governed by the laws of the State of Texas, United States, without regard to its conflict-of-law rules.

​
11. Contact

Questions or notices: open an issue on the mailkit repository.