AI for email, without giving it everything
An assistant can save you real time on email: it remembers the replies you owe, drafts the dull ones and finds the message you can only half describe. It also reads your mail to do it. Here is how mello’s assistant works, what leaves the server and when, and how to keep the parts you want and switch off the rest.
Three rules it follows
- It drafts, you send. Nothing goes out on your behalf. A draft lands in your reply or in Drafts, and you read it, change it and send it yourself.
- One message at a time. For a draft or a reminder, the assistant sees the message in question, not your whole mailbox.
- Every part has a switch. The assistant is on when you start, and Settings → AI turns each feature off, or all of them at once.
What it does for you
- Reply drafts. In a reply, type
/aiand what you want to say, for example/ai yes to Thursday, ask for the agenda, then press Enter. The draft replaces the line, in the language of the email. - Follow-ups. When a message you sent gets no reply in 3 days, the assistant decides whether it needs a nudge. If it does, a follow-up waits in Drafts, and your message is pinned above the inbox under No reply yet.
- Reply reminders. Mail from a person that is still waiting on you after 7 days is pinned under Waiting on you, with a reply already drafted. Reply opens that draft. Done unpins it.
- Suggested to-dos. When someone asks you for something, up to three tasks appear under the message, dated when the email says when. You add them or dismiss them.
- Translation. A message in another language offers translate at the top. show original brings it back.
Archiving or answering a message counts as dealing with it: reminders only come for mail still in your inbox and still unanswered.
Two kinds of search
mello’s ordinary search forgives typos: each word can be one letter off, and accents don’t matter. It runs on mello’s server and involves no AI.
Search by meaning is the other kind. Start your search with ~ and describe what you’re after: ~ receipt for the hotel finds an invoice that never uses the word receipt. To make this work, mello builds an index of your mail with an AI model, as explained below.
What is sent where
Your mail is stored on mello’s servers. The AI features send text to an AI provider, Anthropic or OpenAI, through their business APIs, whose terms say they don’t train their models on it.
| What is sent | When | |
|---|---|---|
| Reply draft, translation | The sender, subject and text of that one message, without quoted history or attachments, at most 12,000 characters, plus your /ai line | Each time you ask |
| Follow-ups | The message you sent | 3 days after, if nobody has replied |
| Reply reminders | The message waiting on you | 7 days after, if it’s still unanswered in your inbox |
| Suggested to-dos | Each new message from a person (not newsletters, notifications or spam) | As it arrives |
| Search by meaning | The sender, subject and first ~2,000 characters of every message, and your searches, to OpenAI | Once for your mailbox, then for each new message |
Two more details. The message is always passed to the model as untrusted content, so an email that says “ignore your instructions” is treated as text, not as an order. And there is an hourly limit of 40 assistant requests per person, so a runaway loop can’t send your mailbox out piece by piece.
Spam filtering may also ask the model for a second opinion on borderline mail only, with a short excerpt.
Turn off what you don’t want
Open Settings → AI. Each switch saves at once.
- AI reply drafts turns the assistant off entirely: no drafts, translations, follow-ups, reminders or suggested to-dos.
- Suggest a follow-up, drafted, when a sent message gets no reply in 3 days, Remind me, with a reply drafted, when mail waiting on me has had no answer for 7 days and Suggest to-dos from new mail turn off one feature each.
- Search by meaning stops the indexing and deletes the index of your mail. Ordinary search keeps working.
A follow-up you set yourself while writing (Remind me if no reply) still comes with the assistant off, just without a draft.
Or bring your own AI
If you already use ChatGPT or Claude, you can connect it to your mailbox instead, or as well. mello offers an MCP connector at https://mcp.mello.mx/mcp. You sign in on mello’s own page, never in the assistant, and tick what it may do: find, read and organize mail, save drafts, work with your calendar, tasks and contacts.
- Sending is off unless you tick it. Without it, the assistant can only prepare drafts for you to send.
- It can’t delete mail for good. The worst it can do is move a message to the Trash.
- It gets what it asks for: the messages, attachments, events and contacts it needs for your request, never your password. Its access lasts an hour at a time, and you can remove it whenever you like.
That assistant’s company then handles what it reads, under its own terms. Connect ChatGPT or Claude walks you through it.
What to look for in any AI email tool
Whichever tool you pick, ask it these questions:
- Can it send by itself? Drafts you review are safe. Sending on its own means a mistake, or a cleverly written email, reaches real people.
- What leaves, and when? One message when you ask is different from your whole mailbox, all the time. Look for a plain list.
- Who processes it, and do they train on it? Look for the provider’s name and its terms, not just “we take privacy seriously”.
- Can you turn each part off? And does turning it off delete what was built, such as a search index?
- Does it ever see your password? A good connector uses its own sign-in and short-lived access you can take back.
- How does it treat what’s in your mail? Email comes from strangers. A tool should treat it as content to read, never as instructions to follow.
- Can you leave with your mail? In mello, Settings → General → Download all my data gives you everything, AI or not.