To add a custom connector to Meta Muse, ask for it in a chat. Muse's connector page only shows apps Meta has listed, and it has no option to add your own. Tell Muse "I want to add my own connector", paste the MCP server URL when it asks (for OwnMailServer, https://api.ownmailserver.com/mcp), and click Connect on the card it shows. Sign in and approve access in the tab that opens, and you're back in Muse with the connector ready.
We tested every step below with the OwnMailServer connector in October 2026: connecting, signing in, asking about real delivery data and sending a real email.
What you need
- A Muse account at muse.ai. You sign in with a Meta account.
- An account with the service you're connecting. For OwnMailServer, that's an account you've signed up for. If you don't have one, you can sign up from the sign-in page in step 3.
- The service's MCP server URL. Ours is
https://api.ownmailserver.com/mcp.
Step 1: Ask Muse to add your connector
Open a chat and write something like:
I want to add my own connector
Muse asks which service, and says it can wire it up from a link to the service's API docs or its MCP server URL. Paste the MCP server URL: it's what Muse actually connects to.
You can look for the app on Muse's connector page first, but if it isn't listed there, there's nothing to click: adding it from the chat is the only route.
Step 2: Click Connect, twice
Muse replies with a connector card showing the service's name and a Connect button. For us, the card says Ownmailserver Mcp.
Clicking Connect opens Meta's notice for custom connectors. It says that Muse may exchange information with the service, that you can disconnect at any time in Settings, and that "Meta doesn't review custom connectors or how they use your information." Read it, then click Connect again.
That warning is fair. A custom connector can do whatever its server lets it, so the next screen matters more than this one.
Step 3: Sign in in the new tab
Muse opens the service's sign-in page in a new browser tab. Ours is on app.ownmailserver.com and asks for one thing, your Work email. Enter the address you signed up with, click Email me a link, and open the one-time link from your inbox. There's no password.
If you see "Enter the email address you signed up with.", the address isn't complete. Check you typed the whole thing, including the domain.
New to OwnMailServer? Click Sign up for early access on the same page. The confirmation email brings you back to finish connecting. We review every signup, so sending waits for approval, usually within one business day, but you can connect and set up your domain before that.
Step 4: Choose what Muse may do, then Allow
Our Allow screen is headed Connect to your account name, and lists what Muse will be able to see:
- Sending statistics, and delivery, bounce and complaint rates
- Your emails' recipients, subjects and delivery timelines, but not their content
- Your suppression list and your domains' DNS health
Below that are two boxes, both ticked:
| Box | What it allows |
|---|---|
| Send email | Sending from your verified domains, up to 50 recipients per email, within your account's daily limit |
| Add and verify sending domains | Adding a domain, showing you the DNS records to publish, and verifying them |
Untick either for less access. With both unticked, Muse can only read. Whatever you choose, it can't remove domains, change other settings or see your API keys, and the screen says so.
Click Allow. A short "Returning to agent.meta.ai…" page appears and sends you back to Muse. That's the Meta address Muse signs in through.
Step 5: Ask your first question
Back in the chat, ask something your own data can answer:
- "How did our email do this week?"
- "Why are emails bouncing?"
- "Are SPF, DKIM and DMARC correct on our domain?"
- "Email jane@example.com that her order has shipped."
When we asked about bounces on a real account, Muse split them into dead addresses, which had been suppressed automatically, and a separate block where Yahoo was deferring mail from the shared IP. It then offered to check the suppression list to confirm the dead addresses wouldn't be mailed again. Muse also keeps each piece of work as a task in its sidebar, such as "Check domain email configuration", so you can find the answer later.
Recipient addresses come back masked, like j***@example.com, unless you ask about that address, so your customers' addresses don't end up in the chat.
What the OwnMailServer connector can do
| Ask about | What you get |
|---|---|
| Setup | What's left before you can send (approval, a verified domain, payment) and what to do next |
| Domains | Add a domain and get the exact DNS records, then verify them (if allowed) |
| Sending | One email at a time from a verified domain, up to 50 recipients (if allowed) |
| Overview | Totals for the last 24 hours and 7 days, domain status, webhook health, pauses and warnings |
| Statistics | Delivery, bounces, complaints and deferrals, by day, mailbox provider or domain |
| Emails | Search by recipient, subject, status or date, and see one email's full timeline |
| Bounces and complaints | Recent bounces with the receiving server's reason, and spam complaints |
| Suppressions | Who you no longer send to, and why |
| Domain health | A live SPF, DKIM, DMARC and return-path check, with the value to publish for anything missing |
An identical email sent again within two minutes isn't resent, so a retry in the chat can't email someone twice. For newsletters and bulk sending, use the API or SMTP rather than a chat. The Muse connector page has more on what it can do and how it handles your data.
If something goes wrong
| What happens | Why | Fix |
|---|---|---|
| Muse says it only has read access, or can't send | It's answering from earlier in the chat, before the connector changed | Ask Muse to refresh its tools, or start a new chat |
| "Enter the email address you signed up with." | The address is incomplete | Type the full address you signed up with |
| No sign-in email | It went to spam, or the address isn't on an account | Check spam, or sign up from the same page |
| Muse can't send even though you allowed it | Your account is awaiting approval or the From domain isn't verified | Ask Muse for your setup status |
| "Too many requests. Try again in 15 minutes." | Several sign-in links asked for in a row | Wait 15 minutes, then use the newest link |
| Muse says the connector is disconnected | It was removed in Muse, or revoked in your dashboard | Add it again from the chat |
When a connector isn't the right tool
A chat is good for questions and the odd email: "why did this bounce?", "is our DNS right?", "send Jane a note". It isn't how your app should send password resets or receipts. For that, connect your app directly with our API or SMTP, and use Muse to keep an eye on the results. If your mail is landing in spam, start with why emails go to spam.
The same connector works in Claude, where it's added from the connectors settings instead; see the Claude connector. It comes with hosted sending at $0.20 per 1,000 emails, with a $10 monthly minimum that covers the first 50,000, and there's no extra charge for using it from Muse.