How to Connect Claude.ai Web to Your Mac
Give Claude.ai (web) direct access to your Mac apps — Mail, Calendar, Contacts, Teams, OneDrive, and 80+ tools. Privacy-first: OAuth via the encrypted Cloud Relay, your data never leaves your 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 stays local.
From Claude.ai web you can ask:
- “Lista mis cuentas de correo”
- “What’s on my calendar this week?”
- “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 Works Today
Claude.ai web was the first major cloud AI client to support the full MCP custom connector flow with Dynamic Client Registration (DCR) and PKCE OAuth 2.0 — the standard required by the MCP spec for cloud clients. This guide is validated end-to-end against production: connector creation, OAuth approval, tool listing, and real tool calls all work as documented.
ChatGPT’s “Build a Connector” beta is in flux as of this writing, so Claude.ai web is the most reliable cloud client for LMCP today. If you’d rather run everything locally with zero cloud transit, use the lmcp connector inside Claude Desktop, Cursor, VS Code, Windsurf, or Zed — LMCP autoconfigures all of them on install.
Privacy Story
Cloud Data Forwarding is off by default and opt-in per machine. When off, the Cloud Relay only exposes setup tools (install, status, troubleshoot) — Claude.ai cannot see your data tools at all.
When you turn it on, your data still comes from your Mac — nothing is stored in the cloud. The bytes transit through the encrypted tunnel between your Mac and the LMCP backend, but they’re never persisted server-side. Turn it off any time from the menu bar and Claude.ai instantly loses access to data tools.
What You Will Need
- macOS 12 (Monterey) or later — Apple Silicon or Intel
- A Claude.ai account — Pro recommended for custom connectors
- An email address — used to register your tunnel and recover access
Step 1: Install LMCP on Your Mac
Open Terminal (Cmd+Space → “Terminal” → Enter) and run:
curl -fsSL https://local-mcp.com/install?ref=guide-claudeai | bashThe installer downloads LMCP, creates a background service, configures local AI clients, and starts the menu bar app. Takes about 30 seconds.
Step 2: Set Up Cloud Relay
Click the LMCP icon in your menu bar (top-right corner of the screen). In the Cloud Relay section, enter your email and click Connect. The dot turns green when the encrypted tunnel is established.
Step 3: Enable Cloud Data Forwarding
By default, the Cloud Relay only exposes setup tools to Claude.ai — not your data. Toggle Cloud Data Forwarding in the menu bar to ON.
Confirm in the dialog. You’ll see your connector URL and token appear right below the toggle, with copy buttons for both. Keep this menu bar window open — you’ll need to copy the token in a moment.
Step 4: Add the Connector in Claude.ai
Open Claude.ai web, then:
- Click your profile avatar → Settings
- In the sidebar, click Connectors
- Scroll to the bottom and click + Add custom connector
- Fill in:
- Name:
LMCP - URL:
https://www.local-mcp.com/mcp
- Name:
- Click Add
Claude.ai automatically discovers our OAuth metadata at /.well-known/oauth-authorization-server, registers itself as a public client via Dynamic Client Registration, and opens an authorization popup.
Step 5: Authorize via the Popup
A popup window opens at https://www.local-mcp.com/oauth/authorize with the LMCP branding and a token paste field. To approve:
- Switch back to the LMCP menu bar icon (top-right corner of the screen)
- In the Cloud Data Forwarding section, click the Copy button next to Token
- Switch to the popup window in your browser
- Paste the token in the field
- Click Authorize
The popup closes automatically. Back in Claude.ai Settings → Connectors, the LMCP entry now shows ~57 read-only tools and ~33 write/delete tools — about 90 total. You only do this OAuth step once; Claude.ai remembers your access token for the lifetime of the connector.
Step 6: Try It in a Chat
Open a new conversation in Claude.ai. Make sure the LMCP connector is enabled in the chat (the connector toggle in the input bar). Then ask in plain language:
- “Lista mis cuentas de correo”
- “What meetings do I have today?”
- “Show me the latest messages in the engineering Teams channel”
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 80+ 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
Turning It Off
Open the menu bar, 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 setup tools, but no data flows through.
Troubleshooting
Claude.ai shows “0 tools” or only setup tools after install
Cloud Data Forwarding is OFF, or Claude.ai cached the catalog from an earlier connection attempt. Open the menu bar and toggle Cloud Data Forwarding ON. If that doesn’t refresh the catalog, uninstall and re-add the connector in Claude.ai Settings → Connectors — that forces a fresh OAuth flow and tools/list call.
Validation error String should match pattern
This is a stale cached catalog from an older LMCP version that used dotted tool names (e.g. setup.install). LMCP 3.0.21+ ships only underscore-form names that Claude.ai accepts. Uninstall and re-add the connector — the new catalog will be fetched and validated cleanly.
Authorization popup says “Token doesn’t match any active LMCP tunnel”
Make sure LMCP is running on your Mac (menu bar dot should be green) and Cloud Data Forwarding is ON. Re-copy the token from the menu bar (it may have rotated) and try again.