Microsoft 365 写入操作 MCP 服务器

m365-actions-mcp-server

MCP server that adds write operations and shared mailbox search to Microsoft 365 — the missing piece that turns Anthropic's read-only ms365 connector into a full bidirectional integration.

Why this exists

Anthropic's built-in Microsoft 365 connector gives Claude powerful read access: searching emails, browsing calendars, finding Teams messages, querying SharePoint. But it cannot send, create, update, or delete anything, and it has limited support for shared/delegated mailboxes. This server fills both gaps.

With both connectors running side by side, Claude can complete full workflows end-to-end: read an email and reply to it, check calendar availability and book a meeting, find a Teams conversation and respond — all without leaving the chat.

Available Tools

Email

Calendar

Teams

How it works with the Anthropic connector

Anthropic ms365 connector (read)     m365-actions-mcp-server (write)
─────────────────────────────────    ──────────────────────────────────
outlook_email_search          ──→    m365_send_mail / m365_reply_mail
outlook_calendar_search       ──→    m365_create_event / m365_update_event
find_meeting_availability     ──→    m365_create_event
chat_message_search           ──→    m365_send_chat_message / m365_reply_to_message
sharepoint_search             ──→    (read-only, no write needed)

Claude automatically chains these tools together. For example: "Find the email from Marco about the invoice and reply saying we'll pay by Friday" triggers outlook_email_search (Anthropic) followed by m365_reply_mail (this server).

Shared Mailbox Search

The m365_search_shared_mail tool fills a gap in the Anthropic connector: reliable search across shared/delegated mailboxes. It accesses /users/{mailbox}/messages directly via Microsoft Graph API, supporting:

• KQL search (from:, subject:, free text) via the search parameter
• Date range filtering via OData filter
• Pagination fallback with client-side filtering when search is unavailable
• Folder targeting (Inbox, Sent Items, etc.)

This is needed because the Anthropic connector outlook_email_search has unreliable indexing for shared mailboxes, and may miss emails in high-volume mailboxes.

The Mail.Read.Shared delegated permission must be granted in Azure AD for this tool to work.

Prerequisites

• Node.js >= 18
• An app registered on Azure AD / Entra ID

Azure App Configuration

1. Go to Entra ID -> App registrations -> New registration
2. Name: M365 Actions MCP Server
3. Supported account types: Single tenant
4. Redirect URI: platform Web, URI http://localhost:3939/auth/callback
5. Create a Client Secret (Certificates & secrets -> New client secret)
6. Add Delegated permissions (API permissions -> Microsoft Graph):
   • Mail.Send
   • Mail.Read
   • Mail.Read.Shared
   • Calendars.ReadWrite
   • Chat.ReadWrite
   • ChannelMessage.Send
   • Team.ReadBasic.All
   • Channel.ReadBasic.All
   • User.Read
   • offline_access
7. Click Grant admin consent

Installation

git clone https://github.com/dfsolutions/m365-actions-mcp-server.git
cd m365-actions-mcp-server
npm install

Configuration

Copy .env.example to .env and fill in your Azure app credentials:

cp .env.example .env

M365_CLIENT_ID=your-client-id
M365_CLIENT_SECRET=your-client-secret
M365_TENANT_ID=your-tenant-id
M365_REDIRECT_URI=http://localhost:3939/auth/callback
M365_USER_EMAIL=your-email@domain.com

Build and Run

npx tsc
node dist/index.js

On the first run, the browser will open for Microsoft login. The token is cached in ~/.m365-actions-tokens.json and reused automatically.

Integration with Claude Desktop / Cowork

Add to your MCP configuration file:

{
  "mcpServers": {
    "m365-actions": {
      "command": "node",
      "args": ["/full/path/to/m365-actions-mcp-server/dist/index.js"],
      "env": {
        "M365_CLIENT_ID": "your-client-id",
        "M365_CLIENT_SECRET": "your-client-secret",
        "M365_TENANT_ID": "your-tenant-id",
        "M365_REDIRECT_URI": "http://localhost:3939/auth/callback",
        "M365_USER_EMAIL": "your-email@domain.com"
      }
    }
  }
}

Alternatively, if the variables are in the .env file inside the project folder:

{
  "mcpServers": {
    "m365-actions": {
      "command": "node",
      "args": ["/full/path/to/m365-actions-mcp-server/dist/index.js"]
    }
  }
}

Authentication

The server uses MSAL with the Authorization Code (delegated) flow:

• On first run, it opens the browser for login
• Saves access + refresh token in ~/.m365-actions-tokens.json
• Automatically renews the token on expiry
• The refresh token lasts ~90 days, then a new login is required

License

MIT