OWA MCP Server

MCP (Model Context Protocol) server for any Microsoft Exchange / OWA (Outlook Web Access) deployment. Gives LLM agents access to email, calendar, directory search, folders, availability, and meeting analytics via 30 tools.

Works with any on-premise or hosted Exchange server that exposes OWA.

Quick Start

# Install
pip install -e .

# Add to your MCP client config with --owa-url
# Then use the login tool to paste your session cookies

Install

Add to your MCP client config. Replace https://owa.example.com with your OWA URL.

Claude Desktop (~/Library/Application Support/Claude/claude_desktop_config.json):

{
  "mcpServers": {
    "exchange": {
      "command": "uvx",
      "args": [
        "exchange-mcp-server",
        "--owa-url", "https://owa.example.com"
      ]
    }
  }
}

Cursor (.cursor/mcp.json):

{
  "mcpServers": {
    "exchange": {
      "command": "uvx",
      "args": [
        "exchange-mcp-server",
        "--owa-url", "https://owa.example.com"
      ]
    }
  }
}

Claude Code (.mcp.json):

{
  "mcpServers": {
    "exchange": {
      "command": "uvx",
      "args": [
        "exchange-mcp-server",
        "--owa-url", "https://owa.example.com"
      ]
    }
  }
}

CLI Arguments

Argument	Default	Required	Description
--owa-url	—	Yes	Base URL of the OWA instance (e.g. https://owa.example.com)
--cookie-file	session-cookies.txt	No	Path to session cookies file
--transport	stdio	—	stdio, sse, or streamable-http
--token-hash	—	For HTTP	SHA-256 hash of the bearer token
--port	8000	—	HTTP/SSE listener port
--host	127.0.0.1	—	HTTP/SSE listener host
--enabled-tools	—	No	Comma-separated whitelist of tool names
--disabled-tools	—	No	Comma-separated blacklist of tool names

Tool filtering examples

# Hide only the most dangerous tools
exchange-mcp-server --owa-url https://owa.example.com \
  --disabled-tools "send_email,delete_email,cancel_meeting"

# Allow only email and calendar tools
exchange-mcp-server --owa-url https://owa.example.com \
  --enabled-tools "get_emails,get_email,send_email,get_calendar_events,create_meeting"

# Whitelist a set, then remove one from it
exchange-mcp-server --owa-url https://owa.example.com \
  --enabled-tools "get_emails,get_email,send_email,delete_email" \
  --disabled-tools "delete_email"
# → only get_emails, get_email, send_email remain

HTTP Transport

Run the server over HTTP (streamable-http or SSE) instead of stdio. This is useful when the MCP client cannot spawn a local process, or when you want to expose the server on a network.

Installation

pip install -e ".[http]"   # adds uvicorn + sse-starlette

Start the server

# Compute the token hash once (store only the hash, never the plaintext token)
TOKEN_HASH=$(echo -n 'my-secret-token' | sha256sum | cut -d' ' -f1)

# stdio (default, for local MCP clients)
exchange-mcp-server --owa-url https://owa.example.com

# streamable-http (recommended for HTTP)
exchange-mcp-server \
  --owa-url https://owa.example.com \
  --transport streamable-http \
  --token-hash "$TOKEN_HASH" \
  --port 8000 \
  --host 127.0.0.1

# SSE
exchange-mcp-server \
  --owa-url https://owa.example.com \
  --transport sse \
  --token-hash "$TOKEN_HASH" \
  --port 8000

CLI arguments

Argument	Default	Required	Description
--owa-url	—	Yes	Base URL of the OWA instance (e.g. https://owa.example.com)
--cookie-file	session-cookies.txt	No	Path to session cookies file
--transport	stdio	—	stdio, sse, or streamable-http
--token-hash	—	For HTTP	SHA-256 hash of the bearer token
--port	8000	—	HTTP/SSE listener port
--host	127.0.0.1	—	HTTP/SSE listener host
--enabled-tools	—	No	Comma-separated whitelist of tool names
--disabled-tools	—	No	Comma-separated blacklist of tool names

Client configuration (HTTP)

{
  "mcpServers": {
    "exchange": {
      "url": "http://127.0.0.1:8000/mcp",
      "headers": {
        "Authorization": "Bearer my-secret-token"
      }
    }
  }
}

Authentication

The server stores only the SHA-256 hash of your token — the plaintext token never touches the filesystem. Every HTTP request must include:

Authorization: Bearer <plaintext-token>

The server hashes the incoming token and compares it with the stored hash. Pass the hash via --token-hash:

echo -n 'my-secret-token' | sha256sum
# → 5e884898da28047151d0e56f8dc6292773603d0d6aabbdd62a11ef721d1542d8

Security notes

• Always use a strong random token.
• Bind to 127.0.0.1 unless you have a reverse proxy / firewall.
• For streamable-http the client must send Accept: text/event-stream.
• The --token-hash is required whenever --transport is not stdio.

Login

The login MCP tool accepts session cookies that you copy from your browser.

1. Log into OWA in your browser.
2. Open DevTools (F12) → Application → Cookies → select your OWA domain.
3. Copy all cookies as name=value pairs (one per line).
4. Call the login tool with the cookies string.

Example cookies string:

X-OWA-CANARY=abc123
CookieAuth1=def456
...

login(cookies="X-OWA-CANARY=abc123\nCookieAuth1=def456\n...")

On success, cookies are saved to session-cookies.txt and all tools become usable. When the session expires, repeat the steps.

Tools (30)

Email (10)

Tool	Description
get_emails	List emails from a folder with filtering
get_email	Get full email content by ID
send_email	Send a new email
reply_email	Reply to an email
forward_email	Forward an email
delete_email	Delete an email
move_email	Move email to another folder
mark_email_read	Mark email as read/unread
download_attachments	Download file attachments from an email
get_email_links	Extract hyperlinks from an email body

Calendar (7)

Tool	Description
get_calendar_events	Get events in a date range (supports recurring expansion)
create_meeting	Create a meeting with attendees
update_meeting	Update an existing meeting
cancel_meeting	Cancel a meeting and notify attendees
respond_to_meeting	Accept, decline, or tentatively accept
download_event_attachments	Download file attachments from a calendar event
get_event_links	Extract hyperlinks from the event description

Directory (1)

Tool	Description
find_person	Search people in Active Directory

Folders (7)

Tool	Description
get_folders	List mail folders with unread counts
create_folder	Create a new mail folder
rename_folder	Rename an existing folder
empty_folder	Empty all items from a folder
delete_folder	Delete a mail folder
move_folder	Move a folder to a different parent
check_session	Check if the OWA session is authenticated

Availability (2)

Tool	Description
find_free_time	Find free slots in your calendar
find_meeting_time	Find common free slots for multiple people

Analytics (2)

Tool	Description
get_meeting_stats	Meeting count statistics for multiple people
get_meeting_contacts	Connection matrix — who you meet with most

Auth (1)

Tool	Description
login	Authenticate to OWA using browser session cookies

Files

exchange_mcp/
  server.py               # FastMCP server entry point
  owa_client.py           # OWA HTTP client
  tools/
    email.py              # Email tools
    calendar.py           # Calendar tools
    people.py             # Directory search
    folders.py            # Folder management & session check
    availability.py       # Free time / meeting time
    analytics.py          # Meeting stats & contacts
    auth.py               # Login tool
pyproject.toml            # Package config