Microsoft 365 MCP Server

ms-365-mcp-server

Microsoft 365 MCP Server

A Model Context Protocol (MCP) server for interacting with Microsoft 365 and Microsoft Office services through the Graph API.

Supported Clouds

This server supports multiple Microsoft cloud environments:

Prerequisites

• Node.js >= 20 (recommended)
• Node.js 14+ may work with dependency warnings

Features

• Authentication via Microsoft Authentication Library (MSAL)
• Comprehensive Microsoft 365 service integration
• Read-only mode support for safe operations
• Tool filtering for granular access control
• Tool presets and dynamic discovery to shrink the tool surface and token usage

Output Format: JSON vs TOON

The server supports two output formats that can be configured globally:

JSON Format (Default)

Standard JSON output with pretty-printing:

{
  "value": [
    {
      "id": "1",
      "displayName": "Alice Johnson",
      "mail": "alice@example.com",
      "jobTitle": "Software Engineer"
    }
  ]
}

(experimental) TOON Format

Token-Oriented Object Notation for efficient LLM token usage:

value[1]{id,displayName,mail,jobTitle}:
  "1",Alice Johnson,alice@example.com,Software Engineer

Benefits:

• 30-60% fewer tokens vs JSON
• Best for uniform array data (lists of emails, calendar events, files, etc.)
• Ideal for cost-sensitive applications at scale

Usage: (experimental) Enable TOON format globally:

Via CLI flag:

npx @softeria/ms-365-mcp-server --toon

Via Claude Desktop configuration:

{
  "mcpServers": {
    "ms365": {
      "command": "npx",
      "args": ["-y", "@softeria/ms-365-mcp-server", "--toon"]
    }
  }
}

Via environment variable:

MS365_MCP_OUTPUT_FORMAT=toon npx @softeria/ms-365-mcp-server

Supported Services & Tools

The server provides 300+ tools covering most of the Microsoft Graph API surface. Each tool maps 1-to-1 to a Graph API endpoint and is defined declaratively in src/endpoints.json.

Personal Account Tools (Available by default)

Email (Outlook), Calendar, OneDrive Files, Excel, OneNote, To Do Tasks, Planner, Contacts, User Profile, Search

Organization Account Tools (Requires --org-mode flag)

Teams & Chats, Online Meetings, Transcripts & Recordings, Attendance Reports, SharePoint Sites & Lists, Shared Mailboxes & Calendars, User Management, Presence, Virtual Events

Required Graph API Permissions

Permissions are requested dynamically based on which tools are enabled. Use --list-permissions to see the exact permissions for your configuration:

# Personal mode (default)
npx @softeria/ms-365-mcp-server --list-permissions

# Organization mode (includes Teams, SharePoint, etc.)
npx @softeria/ms-365-mcp-server --org-mode --list-permissions

# Filtered by preset
npx @softeria/ms-365-mcp-server --preset mail --list-permissions

Shortened. The full README is on GitHub.