MOMSync Application Icon MOMSync's MCP server, momsync-mcp, connects Claude Desktop to the Outlook data already on your Mac. It only ever reads a private copy of that data, it never changes Outlook, and nothing leaves your Mac except the answers it gives Claude.

Before you start

You needNotes
A Mac on macOS 14 or later
Classic Outlook for Mac, with your accounts addedNew Outlook for Mac isn't supported yet.
The MOMSync app, runningNeeded for the sync tools. The calendar, mail and contacts tools work without it.
momsync-mcp, MOMSync's MCP serverA separate program. It isn't included in the App Store version of MOMSync.
Claude DesktopOr any other app that can use MCP servers.
Administrator access to System SettingsTo grant Full Disk Access.

Set it up

  1. Put momsync-mcp somewhere permanent

    Make a bin folder in your home folder and copy the program into it, so its path is ~/bin/momsync-mcp. In Terminal:

    mkdir -p ~/bin
    cp ~/Downloads/momsync-mcp ~/bin/
    chmod 755 ~/bin/momsync-mcp
  2. Tell Claude Desktop about it

    In Claude Desktop choose Settings → Developer → Edit Config, which opens ~/Library/Application Support/Claude/claude_desktop_config.json. Add a momsync entry under mcpServers, keep anything already in the file, and use your own home folder in the path:

    {
      "mcpServers": {
        "momsync": { "command": "/Users/yourname/bin/momsync-mcp" }
      }
    }
  3. Give momsync-mcp Full Disk Access

    Open System Settings → Privacy & Security → Full Disk Access, click +, press Cmd-Shift-G, enter ~/bin/momsync-mcp and choose Open. Make sure its switch is on. Add Terminal the same way if you'll run the commands below.

    macOS treats Outlook's data as another app's private data. Claude Desktop starts momsync-mcp as a separate process, so it needs its own access: giving Claude access isn't enough.

  4. Quit and reopen Claude Desktop

    Full Disk Access only takes effect when an app restarts, and Claude only loads new MCP servers when it starts. After reopening, momsync appears in Claude's list of connectors.

  5. Check everything and build the index

    In Terminal:

    ~/bin/momsync-mcp doctor
    ~/bin/momsync-mcp index

    doctor should show a tick on every line. The first index reads your whole Outlook store and takes one to two minutes for a large mailbox; after that, refreshes take a few seconds. If you skip it, Claude's first request does it instead and takes that long to answer.

Choose what Claude can see

Calendars and contacts start switched on for every account; mail and attachments start switched off. Each account has its own switches, and an account that's switched off is invisible to Claude.

To do thisRun
See current settings and every account~/bin/momsync-mcp config
Allow mail for one account~/bin/momsync-mcp config set you@company.com mail on
Allow mail for every account~/bin/momsync-mcp config set all mail on
Hide one account's calendar~/bin/momsync-mcp config set you@client.com calendar off
Include the local "On My Computer" storeUse local as the account name
Allow attachment downloads (up to 10 MB)~/bin/momsync-mcp config attachments on
Set working hours for free-time searches~/bin/momsync-mcp config hours 08:30-18:00 1,2,3,4,5 (1 = Monday)
Set the time zone~/bin/momsync-mcp config timezone Europe/London
Treat a calendar as yours, shared, a room or holidays~/bin/momsync-mcp config calendar <id> own (ids from list_calendars)

Changes apply to Claude's next request, with no restart needed. Accounts you add to Outlook later appear automatically, with mail off.

Try it

Ask Claude in plain English. Good first requests:

To show your busy time on a client's calendar without revealing other clients' meetings, add a busy-block route in the MOMSync app: Sync Routes → Add Busy Blocks.

Command reference

CommandWhat it does
momsync-mcpRuns the MCP server. Claude Desktop starts it this way; you don't run it yourself.
momsync-mcp doctorChecks Outlook access, the data format, the index and the link to the MOMSync app, and says how to fix anything missing.
momsync-mcp indexBuilds or refreshes the index now. Add --force to re-read everything.
momsync-mcp configShows settings, accounts and file locations. momsync-mcp config help lists every option.
momsync-mcp config profile <folder>Uses an Outlook profile other than "Main Profile". default switches back.
momsync-mcp toolsLists the 20 tools Claude can use.
momsync-mcp call <tool> '<json>'Runs one tool and prints the result, e.g. momsync-mcp call next_meeting '{}'.
momsync-mcp --versionShows the version.

Troubleshooting

Start with ~/bin/momsync-mcp doctor: every ✗ line says what to do.

ProblemFix
"Can't read … Outlook.sqlite"Give Full Disk Access to momsync-mcp itself (for Claude) and to Terminal (for commands you run there), then quit and reopen Claude or Terminal. Granting it to Claude alone isn't enough.
"No Outlook database at …"Your profile isn't called "Main Profile". Run momsync-mcp config profile "<path to your profile folder>".
"schema version … hasn't been tested"An Outlook update changed its data format. Update momsync-mcp; to try anyway, run with MOMSYNC_ALLOW_UNKNOWN_SCHEMA=1.
Results flagged staleClassic Outlook has stopped updating its data, usually because you switched to New Outlook. Switch back to keep MOMSync current.
"Mail access is switched off"Run momsync-mcp config set <account> mail on.
"The MOMSync app isn't running"Open MOMSync. The sync tools need it running; everything else works without it.
"momsync" missing from ClaudeCheck the path in claude_desktop_config.json matches where you put the program, then quit and reopen Claude.
First request is slowIt's building the index. Run momsync-mcp index once to do this up front.
A sync preview shows deletions "held"More than 20 events (or more than 10% of a route's events) would be deleted, so MOMSync is waiting for you. Check them, then press Allow on next sync on the route in the MOMSync app.

Privacy and where files live

Everything stays on your Mac. momsync-mcp sends nothing anywhere except the answers it gives the app that started it. Each refresh copies Outlook's database into a private folder, reads the copy and deletes it; Outlook's own files are never opened or changed.

FileLocation (readable only by you)
Settings~/Library/Application Support/MomSync/mcp-config.json
Index~/Library/Application Support/MomSync/index.sqlite
Activity log (each request, kept 30 days, email searches redacted)~/Library/Application Support/MomSync/audit.log

Text from emails and invitations is marked as coming from other people, and instructions hidden in an email can't make MOMSync act.

To remove the facility, delete the momsync entry from Claude's config, delete ~/bin/momsync-mcp, and delete ~/Library/Application Support/MomSync.

Contact us at info@provulo.com