outlook-personal-mcp

An MCP server that gives Claude Code and Codex full control of a personal Outlook.com mailbox and calendar via the Microsoft Graph API. Written in Python, speaks the MCP stdio transport, and uses per-user device-code OAuth so your credentials never leave your machine. MIT licensed.

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Features

• Mail — list, search, read, send, reply, forward, move, copy, flag, mark read/unread, delete (soft or hard)
• Drafts — create, update, attach local files, send
• Folders — list, create, rename, delete
• Calendar — list calendars, list/search/get/create/update/delete events, respond to invites (accept/decline/tentative), check free/busy availability
• Per-user OAuth — you register your own free Azure app; the server authenticates with your Microsoft account and caches the token locally
• Local stdio — runs as a child process of the MCP host; your mailbox data never transits a third party

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Prerequisites

• Python 3.10 or later
• uv (fast Python package and tool runner) — required at runtime: the server is launched via uvx, and it is not bundled by your MCP host (including Claude Desktop). Install it with curl -LsSf https://astral.sh/uv/install.sh | sh (macOS/Linux) or powershell -c "irm https://astral.sh/uv/install.ps1 | iex" (Windows).
• A personal Microsoft account (Outlook.com, Hotmail, Live, etc.)
• A free Azure app registration (see below — takes about three minutes)

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Azure App Registration

1. Go to https://portal.azure.com → Microsoft Entra ID → App registrations → New registration.

2. Name it anything you like (e.g. outlook-personal-mcp). Under Supported account types choose Personal Microsoft accounts only. No redirect URI is needed. Click Register.

3. Open the app → Authentication → Advanced settings → Allow public client flows → set to Yes → Save. (This is required for the device-code login flow used by this server.)

4. Go to API permissions → Add a permission → Microsoft Graph → Delegated permissions, then add:

   • Mail.ReadWrite
   • Mail.Send
   • Calendars.ReadWrite

   (User.Read is included by default; offline_access is requested automatically at runtime — you do not need to add it.)

5. Copy the Application (client) ID from the Overview page. This is your OUTLOOK_MCP_CLIENT_ID.

Alternatively: create the app with the Azure CLI

If you have the az CLI, the whole registration is one command:

az login --use-device-code --allow-no-subscriptions   # sign in with your personal account

az ad app create \
  --display-name "outlook-personal-mcp" \
  --sign-in-audience PersonalMicrosoftAccount \
  --is-fallback-public-client true \
  --required-resource-accesses '[{"resourceAppId":"00000003-0000-0000-c000-000000000000","resourceAccess":[{"id":"024d486e-b451-40bb-833d-3e66d98c5c73","type":"Scope"},{"id":"e383f46e-2787-4529-855e-0e479a3ffac0","type":"Scope"},{"id":"1ec239c2-d7c9-4623-a91a-a9775856bb36","type":"Scope"}]}]' \
  --query appId -o tsv

The printed appId is your OUTLOOK_MCP_CLIENT_ID. (The GUIDs are the Microsoft Graph delegated scopes Mail.ReadWrite, Mail.Send, and Calendars.ReadWrite.) Note: a brand-new app registration takes a few minutes to propagate to Microsoft's consumer login endpoint — if your first login fails with AADSTS700016 ("application … not found"), wait a few minutes and retry.

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Install & First-Time Login

Run the one-time interactive login. It prints a short URL and a code; open the URL in any browser, enter the code, approve the permissions, and you are done. The token is cached at ~/.config/outlook-personal-mcp/token_cache.bin (mode 600) and refreshed automatically on subsequent runs — you will not be prompted again unless the refresh token expires or is revoked.

OUTLOOK_MCP_CLIENT_ID=<your-app-client-id> uvx mcp-outlook-personal login

To run the latest unreleased code from source instead of the PyPI release, swap mcp-outlook-personal for --from git+https://github.com/salahawad/outlook-personal-mcp mcp-outlook-personal.

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Configure Claude Code

Add the server to your project's .mcp.json (or ~/.claude/.mcp.json for all projects):

{
  "mcpServers": {
    "outlook": {
      "command": "uvx",
      "args": ["mcp-outlook-personal"],
      "env": { "OUTLOOK_MCP_CLIENT_ID": "<your-app-client-id>" }
    }
  }
}

Alternatively, use the CLI: claude mcp add.

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Configure Codex

Add the server to ~/.codex/config.toml:

[mcp_servers.outlook]
command = "uvx"
args = ["mcp-outlook-personal"]
env = { OUTLOOK_MCP_CLIENT_ID = "<your-app-client-id>" }

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Install as a Claude Desktop extension (.mcpb)

This server is also packaged as a Claude Desktop extension (.mcpb). Build the bundle from a checkout:

npx @anthropic-ai/mcpb pack . dist/mcp-outlook-personal.mcpb

Then in Claude Desktop open Settings → Extensions, install the dist/mcp-outlook-personal.mcpb file, and enter your Azure App Client ID (plus any optional settings) when prompted.

Requirement: the extension launches the server with uvx mcp-outlook-personal, so uv must be installed and on your PATH — Claude Desktop does not bundle it (see Prerequisites). Codex and other stdio hosts use the config above instead of the .mcpb.

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Configuration (Environment Variables)

Variable	Required	Default	Description
OUTLOOK_MCP_CLIENT_ID	Yes	—	Azure app's Application (client) ID
OUTLOOK_MCP_AUTHORITY	No	https://login.microsoftonline.com/consumers	MSAL authority URL (change only if you move to a work/school tenant)
OUTLOOK_MCP_TOKEN_CACHE	No	~/.config/outlook-personal-mcp/token_cache.bin	Path to the MSAL token cache file
OUTLOOK_MCP_FILE_ROOT	No	~/.local/share/outlook-personal-mcp/files	Only files under this directory can be read by add_attachment or written by download_attachment
OUTLOOK_MCP_MAX_FILE_BYTES	No	3145728	Maximum bytes allowed for local attachment reads and attachment downloads
OUTLOOK_MCP_ALLOW_PERMANENT_DELETE	No	false	Set to true to enable the permanent_delete tool (irreversible — see below)
OUTLOOK_MCP_DEBUG	No	false	Set to true to log each Graph request's method, URL, and HTTP status code to stderr. Never logs tokens or message content.

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Tools

Account

Tool	Description
whoami	Return the signed-in user's Microsoft account profile

Mail

Tool	Description
list_messages	List messages (newest first); optionally filter by folder or unread-only
search_messages	Full-text search across the entire mailbox (Graph $search)
get_message	Get a single message; optionally include the full body
list_attachments	List a message's attachments (id, name, size, content type)
download_attachment	Download an attachment to a path under OUTLOOK_MCP_FILE_ROOT (refuses to overwrite an existing file)
send_mail	Send an email
reply	Reply to a message (reply_all to reply to everyone)
forward	Forward a message to recipients with an optional comment
move_message	Move a message to another folder
copy_message	Copy a message to another folder
mark_read	Mark a message read or unread
flag_message	Flag or unflag a message
delete_message	Delete a message (moves it to Deleted Items; reversible)
permanent_delete	Permanently delete a message (irreversible). Only available when OUTLOOK_MCP_ALLOW_PERMANENT_DELETE=true

Folders

Tool	Description
list_folders	List mail folders with unread and total message counts
create_folder	Create a mail folder, optionally nested under a parent
rename_folder	Rename a mail folder
delete_folder	Delete a mail folder (moves it to Deleted Items)

Drafts

Tool	Description
create_draft	Create a draft message (not sent)
update_draft	Update a draft's subject and/or body
add_attachment	Attach a local file (a regular, non-symlink file under OUTLOOK_MCP_FILE_ROOT) to a draft
send_draft	Send an existing draft

Calendar

Tool	Description
list_calendars	List the user's calendars
list_events	List events; if start/end (ISO 8601) are given, returns that time window
search_events	Search events by free text
get_event	Get one event including body, attendees, and online meeting link
create_event	Create a calendar event with optional attendees and online meeting
update_event	Update fields on an existing event (only provided fields change)
delete_event	Delete/cancel a calendar event
respond_event	Respond to a meeting invite: accept, decline, or tentative
find_availability	Get free/busy availability for a list of people over a time window

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Permanent Delete

The permanent_delete tool bypasses the Deleted Items folder and removes a message irreversibly. It is disabled by default — when OUTLOOK_MCP_ALLOW_PERMANENT_DELETE is not set (or is false), the tool is not registered with the MCP server at all and will not appear in the tool list.

To enable it, set OUTLOOK_MCP_ALLOW_PERMANENT_DELETE=true in the server's environment block in your .mcp.json / config.toml. Only do this if you understand the consequences: there is no undo and no Recoverable Items path for personal accounts.

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Security

• Token cache is a credential. The file at ~/.config/outlook-personal-mcp/token_cache.bin contains a long-lived refresh token. It is written with mode 600, but treat it like a password — never commit it, never share it, and store it on an encrypted volume.
• Data stays local. The server runs as a child process of Claude Code / Codex over stdio. Your mailbox content is passed directly between the MCP host and the Microsoft Graph API; no third-party relay is involved.
• Revocation. To revoke access, delete the token cache file and/or navigate to https://account.microsoft.com/permissions to remove the Azure app's consent. You can also delete the Azure app registration entirely from the portal.
• File paths. download_attachment writes only under OUTLOOK_MCP_FILE_ROOT and refuses to overwrite existing files. add_attachment reads only regular, non-symlink files under OUTLOOK_MCP_FILE_ROOT. Relative paths are resolved under that root; absolute paths outside it (and any path traversing a symlink) are rejected. Both tools enforce OUTLOOK_MCP_MAX_FILE_BYTES. Review these paths before confirming any tool call that touches the filesystem.

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Development

git clone https://github.com/salahawad/outlook-personal-mcp
cd outlook-personal-mcp
uv venv && uv pip install -e ".[dev]"
uv run pytest
uv run ruff check .

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Privacy Policy

This server runs entirely on your machine and sends data only between your machine and Microsoft's Graph API — no third-party relay, no telemetry, and the maintainer receives nothing. OAuth tokens are cached locally at ~/.config/outlook-personal-mcp/token_cache.bin (mode 600). See PRIVACY.md for the full privacy policy.

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License

MIT — see LICENSE.