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Can an AI read my email? What it can actually do.
Yes, once it can reach your mailbox, and most cannot yet. Most AI subscriptions live inside a chat box: you paste the thread in, read the answer, then retype it into the mail client that actually sends things. A paid AI starts earning its money on the day that carrying stops.
- Reading a message Does not mark it read
- Attachments SHA-256 identical
- Calls a day 5 free, 1,000 on Pro
The problem
Can your AI read your email today? The chat box ceiling
Ask somebody what their AI subscription is good for and you get a warm answer: it writes well, it explains things, it is decent company at 11 at night when a proposal is due. Ask what it does with their email and the answer stops.
That gap isn't about the model. It's about reach. A chat box has no hands. Every document has to be uploaded and every thread pasted in, and every answer has to be copied back out and retyped somewhere else before it does anything in the world.
You are the integration. The AI does the thinking and you do the carrying, which is why a monthly subscription can quietly settle into being a very clever notepad.
Once you see it, you can count it in your own week. Finding the message with the quote in it, and pasting the quote. Writing the reply in the chat box, then writing it again in Outlook because the formatting came across badly. Attaching the file yourself, because of course you do.
None of that is the model failing. All of it is the model being kept at arm's length from the thing you work in.
The question people actually type is some version of "can my AI read my email". Claude and ChatGPT both have Gmail and Outlook connectors of their own now, and each stops somewhere: which plan, which kind of account, whether it can send, whether it opens an attachment. The free Gmail and Outlook connectors in Claude and ChatGPT, compared shows where, beside Mailbox MCP. Without a connector, the answer is still no.
So the useful test of a paid AI isn't how clever it is. It's whether it can reach anything. What an AI can do with your email is the clearest case of that, because email is where the work already is.
Reading a mailbox and being able to send email from it are the 2 things a chat box can't do on its own, however good the model behind it gets.
What came in overnight that actually needs me?
Worked for 184ms
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list_emailsReading the last 12 messages in INBOX 184ms
7 unread. 3 of them want something from you today:
- Dean Alcott wants a quote for a small site and asks if month end is realistic. He was referred by Priya at Meadowbank.
- Sarah at Harbour Lane is chasing the kickoff and needs to book a room. Thursday.
- A message you sent has bounced. Worth looking at before you resend anything.
The rest can wait: a Companies House reminder with 14 days on it, an uptime alert that already resolved itself after 4 minutes, a newsletter, and Tom at Northgate holding 4 packs of the discontinued card stock for you.
One call. 10 messages read, 7 unread, sorted by what wants an answer. Read the detail
Reply to Sarah saying Thursday works, and send her signed agreement back to her.
Worked for 121ms
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search_emailsSearching INBOX for mail from harbourlane.co.uk 12ms -
read_emailOpening "Signed agreement attached" 40ms -
draft_replyDrafting a reply carrying 1 attachment 69ms
Drafted, not sent. It is sitting in your Drafts folder on the same thread as her chase, so it will group properly when it goes.
I have attached Harbour-Lane-Agreement-signed.pdf back to her. That file came straight out of her original message - it never passed through this chat, and I never had to ask you to find it.
Open it in Outlook, change anything you like, and send it yourself.
The attachment moved mailbox to mailbox. It was never uploaded, pasted, or re-typed. Read the detail
Open the printer's invoice and check what it comes to, then get the signed order form off my laptop and back to Tom.
Worked for 3.2s
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search_emailsSearching INBOX for mail from "northgate" 124ms -
read_emailOpening "Invoice NP-4471 - August print run" 69ms -
read_attachmentReading the text inside NP-4471.pdf 2750ms -
create_upload_linkMaking a 30 minute upload link for a file on your computer 34ms - You drop Northgate-order-form-signed.pdf on the link
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check_uploadChecking what arrived at the link 67ms -
draft_replyDrafting a reply to Tom carrying the uploaded file 157ms
The PDF itself says £486 before VAT: £312 for 2,000 A5 leaflets and £174 for the reprint of 250 folded cards. VAT adds £97.20, so £583.20 to pay, 30 days from the invoice date of 29 July. That matches what Tom wrote in the email, which is worth checking because the two do not always agree.
NP-4471.pdf 1 KB Save a copy
That link is signed and it expires. When you click it the file comes straight out of your mailbox; nothing was copied anywhere to make it.
The order form is done too: I made an upload link that lasts 30 minutes, you dropped Northgate-order-form-signed.pdf (1 KB) on it, and it went straight from your computer into a reply to Tom's message about the card stock. It never passed through this chat.
That reply is in your Drafts, not sent: on his thread, with the file attached and a line telling him to go ahead with the 4 packs. Read it and send it from Outlook.
Read from inside the file, not from the email about it. The order form went computer to mailbox without touching the chat. Read the detail
Recorded on 5 and 13 September 2026 against a real mailbox. The tool names, the results and the timings are measured; the correspondents are invented, because real mail from real people does not belong on a public page.
The difference
What changes when it can reach your mailbox
What you would actually type, and what happens when you do. Every answer names the mechanism rather than reaching for an adjective, and every one was measured against a live mailbox before it was written down here.
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Find the invoice from the plumber, some time last spring.
Searches the mailbox itself rather than a summary of it. IMAP search matches substrings, so it finds the word you gave it and not a guess at what you meant.
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Reply to Dave, say yes to Thursday, keep it short.
Threads properly. In-Reply-To and References are carried, so Dave's mail client shows it as a reply and not a new message. Verified in Outlook.
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Clear the newsletters out of my inbox, but do not bin anything.
Moves them. Flags, the original date and the read state all survive the move.
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Send that contract over to the client.
The attachment arrives byte for byte. A real send of a JPEG and a ZIP came out SHA-256 identical at the far end.
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What does the invoice the plumber attached actually come to?
Reads the file, not just the message around it. A PDF or a Word document comes back as text, a spreadsheet as rows with the formulas worked out, a photo as a picture, and a scanned letter as pictures of its pages. Read on real mail: a 5-page invoice, a 16-sheet spreadsheet and an 8-page scan, and the message stays unread.
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What came in overnight that I actually need to deal with?
Answers in one call. The listing carries the first line or 2 of every message, with the quoted history and the signature stripped off, so the shortlist is built without opening anything. And it reads without marking anything read: BODY.PEEK is the IMAP fetch that does not set the Seen flag.
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Who did I last speak to at the accountants, and when?
Lists sender, subject, date, flags and the opening line for the messages that match. The whole body is opened only when you ask about that message.
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Catch me up on the thread with the surveyor.
Reads the whole conversation in one call, oldest first, rather than one call for every message in it. Long threads are capped and the result says so instead of quietly returning the newest few.
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Did that quote ever actually go out, or did I only draft it?
Looks in Sent Items. One copy is filed per send, matched by Message-ID, with no duplicate.
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Put everything from the school in a folder called School.
Creates the folder if it is not there, applying the mail host's own naming rules, then moves the messages into it.
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Archive everything I have already dealt with.
Files them where your own Archive button files them. That is a different folder on each service, and on Gmail it is not a folder at all: archiving there means the message leaves the inbox and carries on living in All Mail. If your mailbox has no archive folder, one is created and subscribed so it actually shows up in Outlook.
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This one is spam, and so are the rest from that sender.
Moves them to the junk folder, which is what your own spam button does and what teaches the mail server to catch the next one. If the filter gets one wrong, taking it back out returns it to the inbox with the date it originally arrived.
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Draft a reply to this one. Do not send it, I want to read it first.
Saves it to Drafts. Sending is a separate tool and needs a separate instruction.
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Email Dave the new date. I have not got his address to hand.
Resolves it from the mailbox's own history, and from your own address book where you have connected one, which comes first. Among the mail, an address you have sent to outranks one that merely arrived from somebody using that name, because a display name on inbound mail can say anything.
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Forward Rachel's last message to my colleague, with the spreadsheet.
Forwards it carrying the attachments and inline images the original carried.
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Send them the whole photo set.
Refuses past 20 MB of attachments on one message. That ceiling is ours rather than the provider's, and it is the total across every file, so 3 files of 7 MB each are refused.
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Send it now, they are on the phone to me.
About 5 seconds to an external domain through Microsoft Graph, and about 10 over SMTP. Both timed.
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Did the one I sent the new client on Monday actually arrive?
Looks for the bounce, in Inbox and Junk, and says whether the failure is permanent or temporary. A send is reported successful when the sending server accepts it, which is not the same as delivered, and the bounce turns up later as its own message.
Every answer above describes what happens to the mail, not what the product supports. The free tier is 5 MCP calls a day on any mailbox, with no card, which is enough to check them on your own mail.
New: routines
AI that checks your email every morning, without being asked
Every question above waits for you to type it. The ones you would type every day can be set once instead: a routine is a scheduled task in your own Claude or ChatGPT that asks for you, at the time you chose, and leaves the answer in your AI app, or the drafts in your Drafts folder. The carrying stopped when your AI could reach the mailbox; a routine stops the asking.
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What came in overnight that I actually need to deal with?
Morning brief
Weekdays at 07:00
What came in since the last brief, who needs you first, and what can wait.
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Who is still waiting on a reply from me?
Replies waiting
Weekdays at 07:30
Drafts a reply to each person still waiting on you, ready for you to check and send.
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Did anybody ever answer the emails I sent last week?
Waiting on
Mondays at 08:30
The emails you sent that nobody has answered, oldest first, with how long each has waited.
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Any bills come in? What do they come to, and when are they due?
Bills and invoices
Weekdays at 08:00
The bills and invoices that arrived, with the totals and due dates read from the attachments.
And for a job none of these fits, your own routine is built from the mail it looks at, what it does with it, and your own words. Each starting time is yours to change.
The mechanism
So what is an MCP server?
Now that the outcome is on the table, the mechanism is a short read.
An AI client can be handed a list of tools. Each tool has a name, a description of what it does and a set of arguments, and the assistant can call one and be told what happened.
The Model Context Protocol is the agreement that lets those tools live somewhere other than inside the AI company's own product. A server publishes tools. A client that speaks the protocol can use them.
Mailbox MCP is one of those servers, and the tools it publishes are mail tools: list a folder, search, open one message, send, reply, forward, move, archive, report spam, create a folder, mark read, flag.
Your assistant never receives a copy of your mailbox. It gets the ability to ask for particular things and to be told the result, which is a much smaller thing to hand over and a much more useful one.
That distinction is not ours alone. Anthropic's own Applied AI team put it more precisely than we would, writing in September 2025:
We're already seeing that smarter models require less prescriptive engineering, allowing agents to operate with more autonomy. But even as capabilities scale, treating context as a precious, finite resource will remain central to building reliable, effective agents.
Anthropic, Effective context engineering for AI agents
Which is exactly why listing a folder returns summaries and a body is fetched one message at a time. Pushing an entire mailbox at a model is not generosity. It is noise, and it costs the model the attention it needed for your actual question.
There is nothing to install. The server is a web address your client calls over HTTPS, added once in that client's connector settings. Your mail application never learns about it, and your mail provider sees ordinary IMAP or Microsoft Graph traffic.
None of it is specific to one assistant: see which AI clients can talk to a remote MCP server, or the longer guide to what an email MCP server is if you want the tool list and the protocol detail. The how it works page follows one request from your sentence to your mailbox and back.
Connecting a mailbox is a URL and a sign-in. Nothing is installed, nothing about your mail moves anywhere, and you can disconnect it in the same place you added it.
Limits
What an AI still cannot do with your email
Everything above is true and none of it is the whole picture. These are the things people are disappointed by, listed before you pay rather than after.
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A calendar has to be connected
Connecting a mailbox doesn't connect a diary. On Microsoft 365, approve calendar access on the same sign-in. On any other mailbox, sign in to Google Calendar, which covers the diary and never the mail, or give the address of your CalDAV calendar server, which Fastmail, iCloud, Nextcloud and most mail hosts run.
Google Calendar gets the same reading, free-time checks, bookings, invitations and answers, but no out-of-office or counter-proposal, because Google has no equivalent of either. On a CalDAV server, what you get depends on the server: it's asked when the calendar connects, and only the tools it supports are offered.
Until a calendar is connected, the mailbox is handed no calendar tools at all, rather than tools that would refuse.
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An address book is a step of its own
A Microsoft 365 mailbox brings its Outlook contacts with the same sign-in. On a mailbox that uses a password, sign in to Google for your Google contacts, or give the address of your CardDAV contacts server.
Whichever it is, your own address book joins the mail: looked up when you ask, changed only when you ask and the book allows it, and never copied. Until then the mailbox gets the email tools alone, and addresses come from its own history.
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Search is literal
Search is substring matching. There is no stemming and no ranking, so a search for invoices does not find a message that only ever says invoice.
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No file store
There is no file store, on any mailbox. An attachment is read on the message it came on, and kept nowhere.
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20 MB a message
Attachments are capped at 20 MB per message in total across every file attached, which is our ceiling rather than a provider's.
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No recovery, no archive
It cannot recover mail that has already been deleted, and it does not back up, export or migrate a mailbox. Archiving a message files it in your own Archive folder, which is not the same thing as keeping a copy of your mail.
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No Exchange shared mailboxes
An Exchange shared or delegated mailbox, the kind with no sign-in of its own, cannot be connected. A mailbox you own can be shared with named people through Team Access, each with their own connection and level.
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Nothing watches your inbox
It doesn't watch your inbox, and nothing reacts to new mail arriving. It acts when you ask it to in a conversation, or when a routine you set runs at the time you chose.
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Accepted, not delivered
A send is reported successful when the sending server accepts the message. Delivery happens afterwards on somebody else's machine, and no mail system can promise that part.
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Both plans have a ceiling
Both plans have a daily ceiling on MCP calls: 5 a day on Free and 1,000 a day on Pro, per mailbox. Pro is a published limit, not an unlimited plan.
What happens to your messages
Nothing is copied into a database of ours, because the server has no database, no cache and no message store at all. Stored credentials are encrypted at rest with AES-256. The security page sets out what is held and what is not, and the questions worth asking any tool that wants your mailbox are written so they work on a competitor as well as on us.
Who should not buy
When this is not worth it
There are people for whom none of the above is worth paying for, and it is cheaper for everybody if they work that out here rather than 3 months in.
- You get a dozen emails a day and you have read them all by 9 in the morning. Filing 12 things is not a job. Automating it is a hobby, and an expensive one once you have spent an evening on the set-up.
- Your inbox is already exactly the way you want it. A filing system somebody else designed is a downgrade however good it is, and an assistant that moves your mail into folders you did not choose will annoy you every day.
- You do not reach for an AI often enough to remember it is there. That is the honest test and it is the one most people skip. If your assistant is a thing you tried twice in July, connecting your mail to it changes nothing.
- You want a new mail app rather than a connection. Mailbox MCP adds no inbox of its own. It gives the AI you already use your real mailbox, and you keep your usual mail program. The 2 approaches to putting AI on your email sets out that difference.
- Your administrator has blocked third-party connectors. Then this is a conversation with them rather than with us, and no amount of enthusiasm on our part changes it.
The person who writes this site also writes about AI subscriptions elsewhere, so what follows is our own opinion quoted back at us rather than an outside verdict. It is here because it argues against spending money, which is the only kind of self-citation worth printing.
If you only dip in occasionally, the free tier of most of these tools will cover you.
Mark McNeece, Best AI Subscription 2026, AI Visibility
And on picking a tier rather than picking a product, from the same article and the same author:
If the answer is 'almost never', buy the budget tier. If the answer is 'constantly, and specifically for the harder questions', buy the full tier.
Mark McNeece, Best AI Subscription 2026, AI Visibility
Both of those are arguments for spending less, and they apply here too. Every mailbox on this service starts free and stays free until you decide otherwise, and the point of the free tier is that you can find out which of the sentences above describes you before any money changes hands.
The set-up
What you need to connect a mailbox
3 things, and there is a fair chance you already have 2 of them.
- An AI client you can add a connector to. The requirement is that it supports remote MCP connectors, which means it can talk to a server it did not start itself. Most now can.
- A mailbox you already own. Gmail, Microsoft 365, or any IMAP host. Nothing moves and no mail is migrated: it stays exactly where it is, with the provider you already pay or do not pay.
- This, in the middle. A URL and a sign-in, added once.
Support moves quickly, so look for connectors, MCP servers, tools or extensions in your own client's settings and trust that over any table on a supplier's website, this one included. The compatibility requirement, and the bridge for clients that only run local servers, is the page that covers it properly.
Setting a connector up may want a desktop or a web session, and that is the step people trip over. Using it afterwards is not restricted the same way, because a remote connector runs from the vendor's cloud and the connection belongs to your account rather than to a device. Add it on a laptop, use it from your phone.
Free AI plans vary, and at least one is enough to run Mailbox MCP. Anthropic's help centre, read on 27 August 2026, says this:
Custom connectors using remote MCP are available on Claude, Cowork, and Claude Desktop for users on Free, Pro, Max, Team, and Enterprise plans. Free users are limited to one custom connector.
Anthropic help centre, custom connectors using remote MCP
One custom connector is one mailbox. Paired with our own free tier of 5 MCP calls a day per mailbox, with no card, that is a working set-up that costs nothing at all. Other clients set their own rules and change them, so check your plan rather than that sentence.
When you outgrow it, Pro is £2.92 a month, paid annually at £34.99 + VAT, per mailbox, and it lifts the ceiling to 1,000 MCP calls a day per mailbox. Both figures are on the pricing page, stated the same way there as here, which is the entire trick and is more than the nearest competitor manages.
Which assistant to put at the front of it is a separate question, and the answer is not a benchmark table. Ethan Mollick, Associate Professor at the Wharton School, wrote in November 2025:
You need to know specifically what YOUR AI is good at, not what AIs are good at on average.
Ethan Mollick, Giving your AI a Job Interview
Which is an argument for connecting a free mailbox to whatever you already have and giving it a week of your own real email, rather than reading a fifth comparison.
If you have not settled on an assistant at all yet, there is a comparison of Claude, ChatGPT, Gemini and Copilot for everyday use on AI Visibility, written by this site's author rather than by an independent reviewer.
Ready to connect one? The set-up guides are per provider: Gmail, Microsoft 365, and any IMAP host.
Questions
Questions people ask
Do I need to pay for an AI to use this?
Not necessarily. Anthropic's help centre, checked 27 August 2026, says custom remote MCP connectors work in Claude, Cowork and Claude Desktop on Free, Pro, Max, Team and Enterprise, with one on Free. One connector is one mailbox, and every mailbox here starts free at 5 calls a day, no card, so a free AI plan and a free mailbox is a real set-up. Other clients differ, so check yours. Pro lifts that to 1,000 a day per mailbox.
Which AI should I get?
That is a different question, answered properly elsewhere. Mailbox MCP's author also writes on AI Visibility, which has a comparison of the main AI subscriptions for everyday use with UK prices. It is linked in the sources at the foot of this page, and it is his own writing rather than an independent review. The short version: work out what you actually use an AI for before paying for a tier that assumes you use it more.
Does the AI read all my email?
No. Listing a folder returns summaries only: sender, subject, date, flags and the first line or 2 of each message, never the whole of one. A full message is fetched one at a time, and only for the messages you asked about; an attachment is opened only when you ask what is inside it. Nothing is copied into a database on our side, because the server has no database, no cache and no message store at all.
Does looking through my inbox mark everything as read?
No. Reading a message through the server does not mark it read. The IMAP fetch it uses is BODY.PEEK, which is the one that deliberately does not set the Seen flag. Marking a message read is a separate tool and needs a separate instruction, so a survey of your inbox leaves the unread count where it was.
Can it manage my calendar as well as my email?
Yes, once a calendar is connected, a separate step from connecting the mailbox. On Microsoft 365, approve calendar access and you get the lot: reading the diary, checking when several people are free, booking your own time, inviting people, answering invitations and setting your out-of-office. Any other mailbox can sign in to Google Calendar, which gets all that except the out-of-office and the counter-proposal, or connect a CalDAV calendar server, which offers only what it supports.
Is this a plugin or an app I have to install?
Neither. There is nothing to install in your mail client and nothing to install on your machine. It is a server your AI client calls over HTTPS, added once in that client's connector settings. The guide on what an email MCP server is covers the mechanism in full if you want it.
What if I already pay for an AI email tool?
Then check you are not paying twice for one job. If you also pay for Claude or ChatGPT, Mailbox MCP lets that AI work the same mailbox inside your conversations, with your usual mail client untouched. Every mailbox starts free at 5 calls a day, and Pro lifts that to 1,000. The AI email assistants page on this site sets the 2 approaches side by side.
Does it work on my phone?
Yes, once it is set up. Adding a connector may want a desktop or a web session depending on the client, which is the step that catches people out. Using it afterwards is not restricted the same way: the connection belongs to your account rather than to a device or an application, so the same mailbox answers from whichever place that client runs.
What happens when I hit the daily limit?
Calls stop for that mailbox until the rolling 24-hour window moves on, and nothing is deleted or changed. The limit is per mailbox rather than per account, so a busy mailbox running out does not stop the others. Free is 5 MCP calls a day and Pro is 1,000 a day, both per mailbox. Pro is a published ceiling, not an unlimited plan.
Attribution
Sources
- Anthropic help centre: get started with custom connectors using remote MCP The plans that can add a custom connector, and the one-connector limit on the free plan. Quoted above. Read 27 August 2026.
- Anthropic: effective context engineering for AI agents The quotation on treating context as a finite resource. Written by Anthropic's Applied AI team, published 29 September 2025, read 27 August 2026.
- Ethan Mollick: giving your AI a job interview The quotation on judging your own AI rather than an average. One Useful Thing, 12 November 2025, read 27 August 2026. Mollick is Associate Professor at the Wharton School and the author of Co-Intelligence.
- Best AI Subscription 2026, on AI Visibility Both quotations in "When this is not worth it". Written by Mark McNeece, who also writes this site, so it is a self-citation and not independent corroboration. Read 27 August 2026.
- Which AI tool should I use, on AI Visibility The comparison of assistants linked above. Same author as this page. Read 27 August 2026.
The measured claims in the examples are ours: the attachment hashes, the threading headers, the sent-copy count and the delivery times were all taken while the engine was being built, against a live mailbox of 26,930 messages, and the 3 attachments were read on through the live service, from files real correspondents had sent. How it works gives each figure with the method beside it.
Keep going
Read next
Stop pasting your email into a chat box.
Connect the mailbox you already own and let the assistant you already pay for reach it. 5 calls a day free, on any mailbox, with no card.