Gmail, Outlook or another mailbox: which works best with an AI agent?
If you are about to let an AI agent answer your business email, you may wonder whether it matters that you use Gmail, Outlook or a mailbox from your web host. The short answer is that all three work, and the agent can do the same things in each. The differences are in how you sign in, how folders behave, and whether a work account needs an administrator's permission. This guide sets out what is the same, what differs, and what to check before you connect.
The short answer
Use the mailbox you already use. Moving providers to suit an AI agent is rarely worth it. Gmail and Outlook connect by signing in through a secure link; any other mailbox connects with its mail server details. Once connected, the agent works the same way and Spaces applies the same limits to all of them.
| Mailbox | How it connects | Worth knowing |
|---|---|---|
| Gmail, personal or Google Workspace | Sign in through a secure link. | Folders are labels. Work accounts may need your administrator to allow the connection. |
| Outlook, personal or Microsoft 365 | Sign in through a secure link. | Work accounts may need your administrator to approve the connection. |
| Other mailboxes (web host, other providers) | Enter your mail server details. | Your provider supplies the details. Some ask for a separate app password. |
What is the same on every mailbox
Whichever provider you use, the agent can do the same jobs through Spaces:
- List emails, newest first, and filter by folder, address or date.
- Read an email with its text and attachments.
- Reply on a thread, or send one email to one person.
- Save a draft for you to check and send yourself.
- Move emails between folders, and mark them read or unread.
- Read the contacts saved in the mailbox.
The limits are the same too. Each mailbox has its own allowance, whatever the provider.
| Action | Spaces limit per account |
|---|---|
| Emails | Up to 100 a day, at least 30 seconds apart |
| New email threads | 8 an hour, 40 a day |
A new chat here is a new email thread. A reply to an email that arrived in the last week is never held back by the daily limits. Spaces sends one email at a time to one person, never bulk email.
Personal account or work account
Both Google and Microsoft offer a personal account and a work account, and they behave differently when you connect a tool.
| Personal account | Work account | |
|---|---|---|
| An @gmail.com address you manage yourself. | Google Workspace, usually on your own domain, managed by an administrator. | |
| Microsoft | An @outlook.com or @hotmail.com address you manage yourself. | Microsoft 365, usually on your own domain, managed by an administrator. |
| Connecting a tool | You approve it yourself during sign-in. | Your organisation may need to allow or approve it first. |
If you are the only person in the business, you are probably the administrator, and approving the connection is a step during sign-in or in your admin settings. If someone else manages your email, such as an IT supplier, ask them before you start, so you are not stuck halfway through.
Folders and labels
Outlook and most other mailboxes use folders: an email lives in one place. Gmail uses labels: one email can have several, and the inbox is itself a label. Tools that connect to Gmail usually show labels as folders, which works fine, with one thing to know: moving an email out of the inbox in Gmail removes the inbox label, while other labels stay on it.
In practice, give the agent simple folder names you create yourself, such as "Answered by agent" and "For a person", and check after a day that emails are ending up where you expect.
Other mailboxes and mail server details
If your email comes from your web host or another provider, you connect it with mail server details. Your provider's help pages list them, usually under a heading about setting up email in another app. Have these to hand:
- The incoming mail server address and port.
- The outgoing mail server address and port.
- Your full email address and the password for the mailbox, or an app password if your provider uses them.
If the connection fails, the usual causes are a typing slip in the server name, the wrong port, or a provider that needs an app password instead of your normal one. Your provider's support can confirm the right details.
What the providers recommend for sending
This is published provider guidance, written in our own words and last updated on 28 Aug 2026. It is advice, not a promise from the platform, and the platform can change what it watches for at any time.
- Gmail allows up to 500 emails a day, but the recommendation is 50 to 100 a day, or 100 to 150 on Google Workspace.
- Start a new mailbox at 20 to 50 emails a day and build up slowly.
- Outlook and other mailboxes should follow the same recommendations as Gmail.
- Spread emails out over the day instead of sending them in bursts.
These recommendations sit well above what a small business answering its customers usually sends. They matter more for a new mailbox, which is why Spaces warms new email threads up gradually.
| Since connecting | New threads an hour | New threads a day |
|---|---|---|
| First 3 days | 3 | 10 |
| Rest of week 1 | 4 | 15 |
| Week 2 | 5 | 22 |
| Weeks 3 and 4 | 6 | 30 |
| After that | 8 | 40 |
Signatures, sent mail and other small things
- Signature: do not assume the signature you set in Gmail or Outlook is added to emails sent through a connected tool. Send a test. If it is missing, put your sign-off in the agent's notes.
- Sent mail: check that replies the agent sends appear in your sent folder, so you have a full record.
- Two-step verification: keep it on. You complete it once on the sign-in page when you connect.
- Signing out: if you change your password or your provider ends the session, the mailbox may need reconnecting.
| What your agent is told | What it means | What to do |
|---|---|---|
| ACCOUNT_NOT_CONNECTED | The platform signed the account out, or asked for a security check. | Open your dashboard and reconnect the account. Sending stays paused until you do. |
If you are switching provider anyway
Some businesses move from a personal Gmail to Google Workspace, or from a web host's mailbox to Microsoft 365, around the time they bring in an AI agent. That is fine, but do it first and connect the new mailbox afterwards. A new mailbox has little history, so treat it gently for a few weeks, as the warm-up above does, and keep the old address forwarding so customers who use it are not lost.
Example: the same reply from two mailboxes
| Who | Message |
|---|---|
| Customer, to a Gmail address | Can I change my booking from the 14th to the 21st? |
| AI agent | Hi Marcus, thanks for letting us know. I have asked Ellie to move you to the 21st and she will confirm by email today. Kind regards, Oak Street Physio |
| Customer, to an Outlook address | Can I change my booking from the 14th to the 21st? |
| AI agent | The same reply. The agent then moves both emails to "For a person" so Ellie can change the diary. |
Names and details are examples.
The provider makes no difference to the conversation. What makes the difference is the notes: the sign-off, what the agent may promise, and which folder it uses. Spaces does not connect to booking systems, so the change itself goes to a person unless the agent has its own access to your diary.
Common mistakes to avoid
- Switching provider just for the AI agent, then starting from a mailbox with no history.
- Trying to connect a work account without the administrator, and getting stuck on an approval screen.
- Assuming your signature is added automatically.
- Typing the wrong server or port for an IMAP mailbox and assuming the tool is broken.
- Treating any mailbox as a newsletter tool. Spaces sends one email at a time to one person.
Notes to give your AI agent
Email:
- Sign off every email as "Kind regards, Oak Street Physio". Our mailbox signature may not be added.
- Reply on the existing thread. Do not start new threads unless I ask.
- After replying, move the email to "Answered by agent". Move anything you should not answer to "For a person".
- Draft, do not send, anything to a new address.
- If Spaces says the mailbox needs reconnecting, tell me and stop.Who you message
Summing up
Gmail, Outlook and other mailboxes all work with an AI agent through Spaces, with the same tools and the same limits. Personal accounts are quickest to connect; work accounts may need an administrator. Gmail uses labels where others use folders, other mailboxes need server details, and signatures are worth testing. Keep the mailbox you have, check those few things, and put your sign-off in the agent's notes.
Pricing
FAQ
Is Gmail or Outlook better for an AI agent?
Neither, really. Both connect by signing in, and the agent can do the same things in each. Use the one you already have.
Can I connect a mailbox from my web host?
Yes. Mailboxes other than Gmail and Outlook connect with their mail server details, which your provider lists in its help pages.
Why does my work account ask for administrator approval?
Google Workspace and Microsoft 365 let organisations control which tools can connect to their accounts. Whoever manages your email may need to allow the connection first.
Are the limits different for Gmail and Outlook?
No. Spaces applies the same limits to every mailbox: up to 100 emails a day, at least 30 seconds apart, with a warm-up for new threads.
Will my email signature be added?
Do not assume so. Send a test through the agent and check. If it is missing, put your sign-off in the agent's notes.
Do Gmail labels work like folders?
Mostly. Tools usually show labels as folders, so the agent can move emails between them. One email can carry several labels in Gmail, which is worth knowing when you check where things went.
Should I switch provider before connecting an AI agent?
Only if you were going to anyway. If so, switch first, keep the old address forwarding, and treat the new mailbox gently for a few weeks.
Can the agent send newsletters from my Gmail?
No. Spaces sends one email to one person at a time, with no bcc and no tracking. Use a newsletter service for campaigns.