How to Connect Claude.ai Web to Your Mac

To use Claude.ai on the web with the apps on your Mac — Mail, Calendar, Microsoft Teams, OneDrive and more — install LMCP and turn on its Cloud Relay. Claude.ai’s chat runs in Anthropic’s cloud, but your inbox, your calendar and your Teams chats live on your Mac; the Cloud Relay is the encrypted tunnel that lets one reach the other. You add LMCP as a custom connector in Claude.ai’s settings, approve it once from a dialog that opens on your Mac, and from then on every tool call routes through the tunnel, runs locally on your machine, and returns a result — typically in under two seconds. No desktop app to install on the Claude.ai side, no separate client: any browser, on any device signed into your account, reaches the same Mac.

What This Lets You Do

Claude.ai web runs in the cloud, but your email, calendar, and Teams chats live on your Mac. With LMCP plus the Cloud Relay, Claude.ai can call tools that run directly on your Mac — over an encrypted WebSocket tunnel — and the data is forwarded to Claude.ai through the relay when requested.

From Claude.ai web you can ask:

• “Summarize my unread emails from this week”
• “What’s on my calendar today?”
• “Search emails about the Q3 budget”
• “Summarize the engineering Teams channel from yesterday”

Claude.ai sends the request to LMCP’s backend, the backend forwards it through the encrypted tunnel to your Mac, your Mac executes the tool locally (Mail.app, Calendar via EventKit, Teams via local cache), and the result returns to Claude.ai — usually in under 2 seconds.

Why Claude.ai Web Instead of Claude Desktop?

Claude Desktop already talks to LMCP: install both, and the desktop app discovers the local lmcp connector over stdio automatically, no relay involved. So why bother adding the same tools to the web version too?

Because the connector lives on your Claude.ai account, not inside an installed app. Add LMCP once in Settings → Customize → Connectors and it is reachable from any browser tab you sign into — a work laptop that will not let you install software, a borrowed computer, a Chromebook — as long as your own Mac stays powered on and LMCP keeps running back home. Claude Desktop, by contrast, only works on the one Mac it is installed on, and only while you’re sitting in front of it.

The trade-off is a network hop. Claude Desktop’s local lmcp connector talks to your Mac over stdio — a pipe between two processes on the same machine — so there is no tunnel and no relay backend. Claude.ai web adds one hop: your request goes to Anthropic, then through the Cloud Relay to your Mac, then back. In practice the difference is invisible — tool calls still land in a second or two — but it’s why Claude Desktop stays the right default when you’re already at your Mac, and Claude.ai web is what you reach for everywhere else.

How the Cloud Relay Works

The Cloud Relay is the piece that makes any of this possible from a browser tab that has no idea your Mac exists. When LMCP starts, it opens a persistent, encrypted connection outbound from your Mac to LMCP’s cloud backend — initiated from your side of the network, the same way your Mac already reaches iMessage or iCloud, so there is nothing to open on your router or firewall.

Claude.ai does not talk to your Mac directly — it can’t, since your Mac has no public address. Instead, Claude.ai’s custom connector points at LMCP’s backend, authenticated by the token in the connector URL. When Claude calls a tool, the backend looks up which open tunnel belongs to that token, forwards the request down it, and your Mac’s LMCP process executes it against the real app — Mail.app for email, EventKit for Calendar, the local Teams cache for channel messages. The result travels back up the same tunnel and out to Claude.ai.

The backend’s job is routing, not processing — it never opens Mail.app itself and never holds an OAuth token for your Microsoft account. All of that lives in the LMCP binary on your Mac, exactly as for Claude Desktop’s local connector. The only difference is that a request arrives over the tunnel instead of stdio.

Privacy: What Travels and What Doesn’t

Cloud Data Forwarding is off by default and opt-in per machine. When off, the connector's tools/list advertises only setup_install (onboarding) — data tools are not listed until you enable forwarding.

LMCP executes local tools on your device. Cloud AI providers and connected services can receive requested data; their terms apply.

In concrete terms: an email’s subject, body and attachments only exist on your Mac and inside Claude’s context window for that conversation. The relay backend sees the encrypted bytes in flight, the way any router sees encrypted packets, but by design does not log, cache or persist the payload once it’s forwarded. What the backend does retain is connection metadata needed to route — which Mac a token maps to, whether the tunnel is currently open — never the content of a tool call.

LMCP executes local tools on your device. Cloud AI providers and connected services can receive requested data; their terms apply. Local execution alone does not establish GDPR or CCPA compliance. Assess the data you authorize, the selected AI provider, connected services and your organizational requirements.

How Is This Different From Uploading Files to the Chat?

You could always attach a .csv export of your calendar or paste an email thread into Claude.ai — that still works. The connector changes three things.

First, it’s live instead of a snapshot: a file you uploaded five minutes ago is already stale if a new email arrives, while a tool call reads Mail.app at the moment you ask, every time. Second, it’s queryable instead of exhaustive — the AI can search for the one thread it needs instead of you exporting and re-uploading every time the question changes. Third, and most important, it can act: create_calendar_event, reply_email and move_email actually change something in your real apps, with a preview before anything sends or moves. A pasted file is read-only by definition — there’s nothing for the AI to write back to.

The cost is the one-time setup of the connector: a couple of minutes now, instead of an export step you’d otherwise repeat every time you wanted a current answer.

What You Will Need

• macOS 12 (Monterey) or later — Apple Silicon or Intel
• A Claude.ai account — Pro recommended for custom connectors

How to Connect Claude.ai to Your Mac

Claude.ai (unlike a desktop app) has no place to enter a token separately, so the token travels in the URL — that’s what binds the connector to your Mac. Keep the URL private; you can rotate the token anytime from LMCP Settings, which invalidates the old URL. (No Copy URL button yet? Update LMCP, or click Copy for the raw token and append it to https://www.local-mcp.com/mcp?token=, replacing any __ with %5F%5F.)

Try It in a Chat

Open a new conversation in Claude.ai, make sure the LMCP connector is enabled (the connector toggle in the input bar), and ask in plain language:

• “List my email accounts”
• “What meetings do I have today?”
• “Show me the latest messages in the engineering Teams channel”
• “Find the OneDrive file about the Q3 budget and summarize it”
• “Create a reminder to follow up with Sarah tomorrow morning”

Claude routes the request through the Cloud Relay to your Mac, which executes the tool and returns the result. You’ll see a “Used LMCP integration” indicator above the response, and the answer usually arrives in under 2 seconds.

What Tools Are Available?

With Cloud Data Forwarding on, Claude.ai sees the same 188+ tools as the local lmcp connector:

• Mail (Mail.app + Outlook): list, read, search, send, reply, move, save attachments
• Calendar: list events, create, delete, check availability
• Contacts: search, list, get details
• Microsoft Teams: list chats, read messages, channel messages (no Graph API needed)
• OneDrive: list, read, write, move, delete, search files
• Notes & Reminders: list, search, create, complete
• Messages: read iMessage chats
• OmniFocus: list tasks, projects, complete, search
• Word, Excel, PowerPoint, PDF: read and create
• Finder & Safari: search files (Spotlight), list folders, bookmarks

Claude.ai Web vs Claude Desktop vs Claude.ai Without a Connector

All three run on the same LMCP install. The difference is where you’re sitting, and whether your Mac has to be part of the picture at all. Here is the honest comparison:

LMCP executes local tools on your device. Cloud AI providers and connected services can receive requested data; their terms apply.

Turning It Off

Open the LMCP menu bar popover → Web AIs section, toggle Cloud Data Forwarding back to OFF. The change is instant: Claude.ai immediately loses access to data tools (it’ll see the “cloud data forwarding is off” message). Your tunnel stays connected for onboarding (setup_install), but no data flows through.

Troubleshooting

Claude.ai shows only setup_install (1 tool)

The token didn’t bind. Two causes: (1) your connector URL is missing the ?token= (you pasted the bare https://www.local-mcp.com/mcp) — re-add it using the full Copy URL value. (2) Cloud Data Forwarding is OFF — toggle it ON in the Web AIs section. After either fix, open the LMCP connector in Claude.ai and use ⋮ → Refresh tools list (or remove and re-add).

Pasted the URL but still 1 tool

Claude.ai collapses a literal __ (double underscore) in a URL to a single _, which corrupts the token. Always use the Copy URL button (it percent-encodes the token), or hand-replace __ with %5F%5F in the URL.

Connector connects but tools fail

Make sure LMCP is running (menu bar dot is green) and Cloud Data Forwarding is ON. If the token was rotated, copy a fresh URL via Copy URL and re-add the connector.

Claude.ai says it can’t reach your Mac

Every tool call travels all the way to your Mac and back — there is no cached copy in between. LMCP has to be running and your Mac has to be awake. Open the LMCP menu bar: the dot should be green and Cloud Relay should read Connected. A Mac that’s asleep, shut down, or has LMCP quit leaves Claude.ai with nothing to call.

Clicked Connect but nothing happened on my Mac

The approval dialog opens on your Mac, not in the browser — check for it behind another window, or in the LMCP menu bar for a pending request. If you genuinely don’t see one, click Connect again in Claude.ai to re-issue it.

Real-World Workflows

The connector is most useful exactly when you’re not at your own Mac:

Triage from your phone’s browser

Your Mac stays on your desk; Claude.ai reaches it through the tunnel exactly as it would from a laptop — nothing to install on the phone, just the browser.

Catch up on Teams before a meeting

Two apps, one prompt: Claude reads the Teams channel cache and Calendar in the same turn.

A weekly digest from a machine that isn’t yours

Sign into Claude.ai on a work laptop or a shared computer, and the connector you set up once is already there.

What Else Can LMCP Do?

Email and Teams are two of 188+ tools LMCP exposes. See Apple Mail with Claude Desktop, Microsoft Teams without API keys, or the ChatGPT Cloud Relay guide. The full list of guides covers every app the same install reaches.

Frequently Asked Questions

Can Claude.ai on the web access my Mac apps?

Yes. With LMCP's token-authenticated custom connector, Claude.ai web can read your email, manage your calendar and search Teams — requests route to your Mac and run locally.

Is it free, and do I need API keys?

LMCP is free and needs no API keys. Adding a custom connector on Claude.ai's side uses a paid Claude.ai plan — that's an Anthropic requirement, not an LMCP one.

How is this different from Claude Desktop?

Claude Desktop connects to LMCP locally over stdio; Claude.ai on the web reaches your Mac through the encrypted Cloud Relay tunnel. Same tools, either way — see the full comparison above if you’re deciding which one to set up first.

Does my Mac need to be on and LMCP running?

LMCP executes local tools on your device. Cloud AI providers and connected services can receive requested data; their terms apply.

Can I use Claude Desktop and Claude.ai web at the same time?

Yes, they don’t conflict. Claude Desktop talks to LMCP over local stdio, Claude.ai web talks to it through the Cloud Relay — two independent connectors to the same tools, and turning one off doesn’t affect the other.

What if I think my connector URL or token leaked?

Rotate it right away from the LMCP menu bar. A new token invalidates the old URL immediately, so whoever had it can no longer authenticate to your Mac — then update the connector in Claude.ai with the freshly copied URL.

Related Guides

• How to Connect ChatGPT to Your Mac (Cloud Relay)
• How to Give Claude Desktop Access to Email on Mac
• Can AI Read Your Emails Without Sending Them to the Cloud?