Outlook MCP

outlook-mcp

MCP server for Microsoft Outlook personal accounts via Microsoft Graph API.

Personal Microsoft accounts only — @outlook.com, @hotmail.com, @live.com. Work/school accounts (Entra ID) are not supported in v1.

Disclaimer: Independent open-source project. Not affiliated with, endorsed by, or supported by Microsoft Corporation. "Outlook" and "Microsoft Graph" are trademarks of Microsoft.

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Who this is for

You'll like this if you're:

• An agent builder wiring Outlook into your own infra (OpenClaw, Claude Code, Cursor, custom MCP host) and want a typed tool surface — not stdout you have to parse
• Building on personal Microsoft accounts (Outlook.com / Hotmail / Live) and want full control: BYO Azure app, no enterprise consent flow, no shared client ID
• Looking for real coverage — mail, calendar, contacts, to-do, drafts, folders, batch ops, threading — instead of a mail-only or calendar-only wrapper
• Security-conscious: tokens in the OS keyring (Keychain on macOS), granular allow_categories, optional read_only mode, zero telemetry

This isn't for you if you need work/school M365 accounts (use Microsoft's official tooling — Entra ID auth and admin-consent flows are out of scope here), or if a basic mail-only client would suffice (this has 62 tools — way more than you need for "read my inbox").

How it differs from other Outlook tools you'll find

This is the only first-class MCP server in the personal-Outlook space — most alternatives are bash scripts or skill-shaped CLI wrappers the agent shells out to. That distinction matters: the agent gets typed tool schemas with structured args/returns, not stdout it has to parse. Other things you won't find elsewhere: /$batch-optimized triage (10-20× faster on bulk ops), recursive folder ops with name resolution, granular per-category permissions, multi-account support, and full attachment write paths including >3MB upload sessions for drafts.

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What This Enables

Give your AI agent full Outlook access. Example prompts that just work:

• "Summarize my unread email from the past 24 hours and flag anything time-sensitive."
• "What's in my Focused Inbox right now? Anything in Other that looks like it belongs up top?"
• "Any shipping updates in my inbox? Track what I'm waiting on and when it's supposed to arrive."
• "Scan my email for upcoming subscription renewals — what's about to auto-charge in the next two weeks?"
• "I've got a trip to Seattle next week — check my calendar for the itinerary and create a To Do task with a packing checklist."
• "Draft a reply to the last message from my sister saying I'll call her this weekend."
• "Move all newsletter and promotional email from this week to a 'Read Later' folder — batch 20 at a time."

The server exposes 62 discrete tools so the agent can compose its own workflow — read, triage, write, schedule, track tasks — without hardcoded macros.

Works With

• OpenClaw — native MCP support, available via ClawHub
• Claude Code — add to ~/.claude/settings.json under mcpServers
• Cursor — MCP-compatible
• Any MCP client — it's a standard stdio MCP server

Listed on the official MCP Registry as io.github.mpalermiti/outlook-mcp.

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Features

62 tools across 13 categories:

• Auth (1) -- auth status check (login is via CLI)
• Mail Read (7) -- list inbox (with Focused Inbox filter), read message, bulk read by ID via $batch, search (KQL), list folders, delta-sync inbox changes, composed "since last call" digest across mail/events/contacts
• Mail Write (3) -- send, reply/reply-all, forward
• Mail Triage (9) -- move, delete (soft by default), flag, categorize, mark read/unread, reclassify (Focused Inbox), list/set/delete per-sender Focused Inbox overrides
• Calendar Read (3) -- list events (with recurring expansion), get event details, delta-sync event changes
• Calendar Write (4) -- create, update, delete, RSVP (accept/decline/tentative)
• Contacts (7) -- list, search, get, create, update, delete, delta-sync changes
• To Do (6) -- list task lists, list/create/update/complete/delete tasks
• Drafts (5) -- list, create, update, send, delete
• Attachments (5) -- list, download, send-with-attachments, attach-to-draft, remove-draft-attachment
• Folder Management (3) -- create, rename, delete mail folders
• Threading and Batch (3) -- list thread, copy message, batch triage
• User and Admin (6) -- whoami, list calendars, list categories, mail tips, accounts

Design principles:

• BYOID -- Bring Your Own ID. You register your own Azure AD app. No shared client ID.
• Zero telemetry -- no analytics, no local caching, no third-party calls.
• Token storage -- OS keyring via azure-identity (macOS Keychain, Windows Credential Store, Linux Secret Service).
• Input validation -- all inputs validated (email, Graph IDs, OData, KQL, datetimes) before any API call.
• Read-only mode -- set read_only: true in config to block all write operations.
• Soft delete -- delete moves to Deleted Items by default. Hard delete requires explicit permanent: true.
• Timezone-aware -- calendar operations respect your configured IANA timezone.

Agent-friendly shape (1.8.0)

Two pure-code upgrades that make the same 57 tools cheaper and more recoverable for AI agents:

• Concise mode — pass concise=True to the five high-volume read tools (outlook_list_inbox, outlook_read_message, outlook_search_mail, outlook_list_events, outlook_list_thread) to drop bulky fields: full message bodies, per-event attendee lists, quoted prior-message text in threads, body previews/categories on inbox listings. Typical payload reduction ~10×. Default concise=False preserves the existing response shape — strict backward compat.

• Structured Graph errors — every tool wraps msgraph SDK exceptions into {code, message, action} responses with operator-friendly recovery hints: re-auth on 401, ROADMAP pointer on 403/ErrorAccessDenied (known unsupported-endpoint dead-ends), re-list on 404/ErrorItemNotFound, back-off on 429, retry on 503. OutlookMCPError subclasses and validation errors pass through unchanged.

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Azure AD App Registration

You need to register a free Azure AD app to get a client ID.

Prerequisites (Personal Microsoft Accounts)

Microsoft has deprecated app registration for personal accounts without an Azure AD tenant. You need to create a free Azure account first:

1. Go to azure.microsoft.com/free and sign up with your personal @outlook.com account. Requires a credit card for identity verification but won't charge you. This creates a proper Azure AD tenant.

Register the App

1. Go to App Registrations and sign in with your @outlook.com account.

2. Click "+ New registration" and fill in:

   • Name: anything except Microsoft-branded terms (e.g. mp-outlook-mcp — names like "Outlook MCP" will be rejected)
   • Supported account types: select "Personal Microsoft accounts only"
   • Redirect URI: leave blank

3. Click Register. Copy the Application (client) ID from the overview page.

4. Go to Authentication (Preview) → Settings tab → toggle "Allow public client flows" to Yes → Save.

5. Go to API permissions → Add a permission → Microsoft Graph → Delegated permissions → add:

   • Mail.ReadWrite, Mail.Send
   • Calendars.ReadWrite
   • Contacts.ReadWrite, Tasks.ReadWrite
   • User.Read, offline_access

No client secret is needed. The device code flow uses public client auth.

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Quick Start

Install

Option A — from PyPI (recommended):

uv tool install outlook-graph-mcp
# or: pipx install outlook-graph-mcp
# or: pip install outlook-graph-mcp

Option B — from source:

git clone https://github.com/mpalermiti/outlook-mcp.git
cd outlook-mcp
uv sync

Configure

Create ~/.outlook-mcp/config.json:

{
  "client_id": "YOUR_APPLICATION_CLIENT_ID",
  "tenant_id": "consumers",
  "timezone": "America/Los_Angeles",
  "read_only": true
}

The only required field is client_id. Everything else has sensible defaults. Start with read_only: true — flip to false when you're comfortable.

Register with your MCP client

If installed from PyPI:

{
  "mcpServers": {
    "outlook": {
      "command": "outlook-mcp"
    }
  }
}

If installed from source:

{
  "mcpServers": {
    "outlook": {
      "command": "uv",
      "args": ["--directory", "/path/to/outlook-mcp", "run", "outlook-mcp"]
    }
  }
}

For OpenClaw, use the openclaw mcp CLI — it writes to mcp.servers in ~/.openclaw/openclaw.json for you:

# If installed from PyPI:
openclaw mcp set outlook '{"command":"outlook-mcp"}'

# If installed from source:
openclaw mcp set outlook '{"command":"uv","args":["--directory","/path/to/outlook-mcp","run","outlook-mcp"]}'

# Verify:
openclaw mcp list
openclaw mcp show outlook --json

Restart the OpenClaw gateway after registering. See the OpenClaw MCP docs for SSE/HTTP transport variants.

Authenticate

Run this once on the machine where the MCP server will run:

uv run outlook-mcp auth

You'll get a URL and a code. Open the URL in any browser, enter the code, and sign in with your Microsoft account. Tokens are cached in the OS keyring — the MCP server picks them up automatically.

Other CLI commands:

uv run outlook-mcp status   # Check auth status
uv run outlook-mcp logout   # Clear credentials
uv run outlook-mcp serve    # Start MCP server (default, used by OpenClaw/Claude)

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Troubleshooting

SSL: CERTIFICATE_VERIFY_FAILED on Linux

If auth fails with [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate, your Python environment can't find the system CA bundle. This is common on minimal/container Linux images and with the isolated venv from uv tool install.

Point Python at your system CA bundle. Set both variables — auth (via azure-identity → requests) reads REQUESTS_CA_BUNDLE, while the delta/$batch paths (via httpx) read SSL_CERT_FILE:

export SSL_CERT_FILE=/etc/ssl/certs/ca-certificates.crt      # httpx + Python ssl
export REQUESTS_CA_BUNDLE=/etc/ssl/certs/ca-certificates.crt  # azure-identity auth

The path varies by distro: Debian/Ubuntu use /etc/ssl/certs/ca-certificates.crt; RHEL/Fedora use /etc/pki/tls/certs/ca-bundle.crt. If the file is missing, install your distro's CA package (ca-certificates). Set these in the same environment your MCP client launches the server from so they apply at runtime, not just to the one-time auth command.

Token cache stored unencrypted (Linux)

A one-time startup warning about the token cache falling back to plaintext means libsecret/PyGObject isn't importable — see Privacy and Security for the fix.

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Tool Reference

Auth

Tool	Description
outlook_auth_status	Check if authenticated and whether read-only mode is active.

Note: Authentication is handled via the CLI (outlook-mcp auth), not through MCP tools. See Authenticate above.

Mail Read

Tool	Description
outlook_list_inbox	List messages in a folder. folder accepts display names, well-known names, or Graph IDs. Filter by read status, sender, date range, Focused Inbox classification. Pagination via skip.
outlook_read_message	Get full message by ID. Format: text, html, or full (both). Pass include_deferred_send=True to also surface the draft's scheduled delivery time.
outlook_read_messages	Bulk read up to 20 messages by ID via Graph $batch in one round-trip. Per-message shape matches outlook_read_message byte-for-byte for the same (format, concise, include_deferred_send). Partial-failure tolerant: 404s on some IDs surface in failures[] without failing the whole call. Use NOT N outlook_read_message calls.
outlook_search_mail	Search mail using KQL query. Optionally scope to a folder by name or ID.
outlook_list_folders	List mail folders with counts, parent_id, and child_count. Pass recursive=true to walk the full folder tree (subfolders included).
outlook_list_inbox_delta	List only inbox changes since the last call. First call returns a full snapshot plus a delta_token; subsequent calls (token passed back) return only added/updated/deleted items. Deletes come back as {id, is_deleted: True}. Cursor is stateless — agent persists and replays.
outlook_changes_since	One structured "since last call" digest composing mail/events/contacts deltas. Returns counts + urgent_flagged mail + top-5 by_sender + new/cancelled events. Each resource has an independent delta_token; stale-token recovery (HTTP 410) auto-resyncs that resource and surfaces _meta.resync. First-call snapshot is filtered to fallback_window_hours (default 24). Designed for recurring agent loops.

Mail Write

Tool	Description
outlook_send_message	Send email. Supports TO/CC/BCC, HTML body, importance level.
outlook_reply	Reply or reply-all to a message.
outlook_forward	Forward a message to one or more recipients with optional comment.

Mail Triage

Tool	Description
outlook_move_message	Move a message to a folder by name or ID.
outlook_delete_message	Delete a message. Soft delete (Deleted Items) by default. permanent: true for hard delete.
outlook_flag_message	Set follow-up flag: flagged, complete, or notFlagged.
outlook_categorize_message	Set categories on a message.
outlook_mark_read	Mark a message as read or unread.
outlook_reclassify_message	Move a message between Focused Inbox and Other (focused / other).
outlook_list_inbox_overrides	List Focused Inbox per-sender override rules.
outlook_set_inbox_override	Upsert a per-sender Focused Inbox override (focused / other). Case-insensitive sender matching; PATCH-if-exists, else POST.
outlook_delete_inbox_override	Delete a Focused Inbox override by ID.

Calendar Read

Tool	Description
outlook_list_events	List events in a date range. Expands recurring events. Configurable via days, after, before.
outlook_get_event	Get full event details: attendees, body, online meeting URL, recurrence.
outlook_list_events_delta	List only event changes inside a window since the last call. start and end (ISO 8601) required on the first call (Graph constraint — no whole-calendar sync). Deletes come back as {id, is_deleted: True}. Cursor is stateless.

Calendar Write

Tool	Description
outlook_create_event	Create event with location, attendees, recurrence, online meeting support.
outlook_update_event	Update event fields (subject, time, location, body). Only patches changed fields.
outlook_delete_event	Delete a calendar event.
outlook_rsvp	RSVP to an event: accept, decline, or tentative. Optionally include a message.

Contacts

Tool	Description
outlook_list_contacts	List contacts with cursor pagination.
outlook_search_contacts	Search contacts by name or email.
outlook_get_contact	Get full contact details by ID.
outlook_create_contact	Create a new contact.
outlook_update_contact	Update contact fields.
outlook_delete_contact	Delete a contact.
outlook_list_contacts_delta	List only contact changes since the last call. Deletes come back as {id, is_deleted: True}. Cursor is stateless.

To Do

Tool	Description
outlook_list_task_lists	List To Do lists.
outlook_list_tasks	List tasks with status filter and pagination.
outlook_create_task	Create task with due date, importance, recurrence.
outlook_update_task	Update task fields.
outlook_complete_task	Mark task as completed.
outlook_delete_task	Delete a task.

Drafts

Tool	Description
outlook_list_drafts	List draft messages with pagination.
outlook_create_draft	Create a draft. Supports scheduled delivery via deferred_send_datetime (server-side, Outlook-desktop-compatible "Delay Delivery").
outlook_update_draft	Update draft fields. Accepts is_html=True for HTML bodies and deferred_send_datetime to set or clear the scheduled delivery time.
outlook_send_draft	Send an existing draft.
outlook_delete_draft	Delete a draft.

Attachments

Tool	Description
outlook_list_attachments	List attachments on a message.
outlook_download_attachment	Download attachment and save decoded bytes to a file.
outlook_send_with_attachments	Send message with file attachments (auto upload session for >3MB).
outlook_attach_to_draft	Add attachments to an existing draft (auto upload session for >3MB).
outlook_remove_draft_attachment	Remove a single attachment from a draft.

Folder Management

Tool	Description
outlook_create_folder	Create mail folder (top-level or nested).
outlook_rename_folder	Rename a mail folder.
outlook_delete_folder	Delete a mail folder (refuses well-known folders).

Threading and Batch

Tool	Description
outlook_list_thread	Get all messages in a conversation thread.
outlook_copy_message	Copy a message to another folder.
outlook_batch_triage	Batch move/flag/categorize/mark_read (max 20 per call). Single Graph /$batch round-trip — 10-20× faster than per-message calls for large triage.

User and Admin

Tool	Description
outlook_whoami	Get current user profile.
outlook_list_calendars	List available calendars.
outlook_list_categories	List category definitions with colors.
outlook_get_mail_tips	Pre-send check (OOF, delivery restrictions).
outlook_list_accounts	List configured accounts.
outlook_switch_account	Switch active account.

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Configuration

Config lives at ~/.outlook-mcp/config.json (created with 0600 permissions).

Field	Type	Default	Description
client_id	string	null	Azure AD application (client) ID. Required for auth.
tenant_id	string	"consumers"	Azure AD tenant. Use "consumers" for personal Microsoft accounts.
timezone	string	"UTC"	IANA timezone (e.g. "America/New_York"). Used for relative date computations in calendar tools.
read_only	bool	false	When true, all write tools (send, reply, move, delete, create, update, RSVP) return an error.
allow_categories	list[string]	[]	Optional. Restrict write tools to specific categories (see below). Empty list = all writes allowed when read_only: false.

Toolset selection (optional) — OUTLOOK_MCP_TOOLSETS

All 62 tool schemas load into the client's context every turn (~8.6k tokens). A client that only needs part of the surface can set the OUTLOOK_MCP_TOOLSETS environment variable to a comma-separated list of tool groups, and only those load. The account group (auth / identity) is always available.

# e.g. a recurring mail + calendar agent: ~30 tools instead of 62 (~52% fewer tool tokens/turn)
OUTLOOK_MCP_TOOLSETS="mail,calendar,digest,delta"

Groups: mail, drafts, attachments, calendar, contacts, todo, folders, digest, delta, admin. Unset (the default) loads everything — fully backward compatible. This only affects which tools are advertised; enabled tools behave identically.

Granular Write Permissions (optional)

By default, read_only: false unlocks all write tools. For finer control, set allow_categories to restrict write access to specific categories. Read tools (list, search, get) are always allowed — allow_categories only narrows the write surface.

Available categories:

Category	Tools	Risk
mail_drafts	create/update/delete draft	Safe — drafts only, no send
mail_triage	move, delete (soft), flag, categorize, mark read, copy, batch	Moderate — reversible except hard delete
mail_folders	create/rename/delete folder	Moderate
mail_send	send, reply, forward, send_draft, send_with_attachments	Dangerous — sends email on your behalf
calendar_write	create/update/delete event, RSVP	Moderate — creates calendar entries
contacts_write	create/update/delete contact	Moderate
todo_write	create/update/complete/delete task	Safe — your own task list

Example policies:

Draft-only assistant (agent can compose drafts, you review and send):

{ "read_only": false, "allow_categories": ["mail_drafts", "mail_triage", "todo_write"] }

Calendar-only (agent can manage your schedule, nothing else):

{ "read_only": false, "allow_categories": ["calendar_write"] }

Full write access (agent can do everything):

{ "read_only": false }

Read-only (safest default, no writes):

{ "read_only": true }

When allow_categories is set, any tool in a non-allowed category returns a permission-denied error (PermissionDeniedError) naming the blocked category. When allow_categories is empty (or unset) and read_only is false, all write tools are permitted. read_only: true always takes precedence — if set, all writes are blocked regardless of allow_categories. Unknown category names are rejected at config load time with a validation error; only the seven names above are accepted.

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Privacy and Security

• Zero telemetry. No analytics, no tracking, no usage data collected.
• Zero local caching. Every call goes directly to Microsoft Graph. No local email/calendar storage.
• Zero third-party calls. The server only talks to graph.microsoft.com and login.microsoftonline.com.
• Token storage. OAuth tokens are persisted via azure-identity's TokenCachePersistenceOptions. On macOS the OS Keychain is used; on Windows, DPAPI; on Linux with PyGObject/libsecret available, gnome-keyring. On Linux without libsecret (e.g. the isolated venv created by uv tool install), tokens fall back to a 0600 plaintext file at ~/.IdentityService/ and the MCP logs a one-time warning at startup. For encrypted storage on Linux, install python3-gi gnome-keyring libsecret-1-0 and re-create the venv with --system-site-packages.
• No logging of sensitive data. Message bodies, recipient addresses, and tokens are never logged.
• Config permissions. Config directory is 0700, config file is 0600. Symlinked configs are rejected.
• Input validation. All user inputs (email addresses, Graph IDs, OData filters, KQL queries, datetimes) are validated and sanitized before reaching the Graph API.

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Development

# Install dev dependencies
uv sync --extra dev

# Run tests
uv run pytest

# Lint
uv run ruff check src/ tests/

# Format
uv run ruff format src/ tests/

# Run server locally (stdio)
uv run outlook-mcp

Requirements: Python 3.10+

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Roadmap

• Inbox Rules -- list, create, delete rules
• Advanced mail -- raw MIME export, internet message headers
• Calendar -- cancel event (with attendee notification)
• Checklists -- checklist items on To Do tasks
• Enterprise (Entra ID) -- work/school account support

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License

MIT. See LICENSE.