Graph MCP

Graph MCP is a Node.js MCP server that connects Claude Code and Codex to Microsoft Teams, Outlook mail and calendar, online meetings, OneDrive, users, and presence through Microsoft Graph. It runs locally over stdio and requires Node.js 22 or newer.

What it does

Graph MCP exposes exactly 44 tools:

Category	Tools
Authentication	Check status, log in with browser or device code, log out
Users and presence	Read your profile, search users, read presence, set your presence
Search	Search messages across chats and channels
Chats	List chats, read or send messages, create chats, list members
Teams and channels	List teams and channels, read or send messages and replies, list members
Calendar	List calendars and events, get, create, update, or delete events
Mail	List, read, or search mail, send or reply, list or download attachments
Meetings	List online meetings, transcripts, and recordings; read transcript content or recording URLs
Files	Browse or search OneDrive, download or upload content, create sharing links

Prerequisites

Node.js 22 or newer.
A Microsoft Entra ID app registration configured as a public client on the Mobile and desktop applications platform.
Redirect URI http://localhost:3000/auth/callback.
No client secret. Graph MCP uses delegated user authentication.

Add these exact delegated permissions to the app registration:

offline_access
openid
profile
User.Read
User.ReadBasic.All
Chat.Read
Chat.ReadWrite
ChatMessage.Send
ChannelMessage.Read.All
ChannelMessage.Send
Team.ReadBasic.All
Channel.ReadBasic.All
ChannelMember.Read.All
Calendars.ReadWrite
Mail.Read
Mail.Send
Presence.Read
Presence.Read.All
Presence.ReadWrite
OnlineMeetings.Read
OnlineMeetingTranscript.Read.All
OnlineMeetingRecording.Read.All
Files.ReadWrite.All

Some organizations require administrator consent for one or more permissions. Use the least privilege your deployment needs and follow your organization's approval process.

Install

Claude Code plugin

From a local checkout of this repository:

claude plugin marketplace add /absolute/path/to/Graph-MCP --scope user
claude plugin install graph-mcp@graph-mcp --scope user

The marketplace installs the self-contained plugin under Claude's plugin cache. Its MCP server launches from the installed plugin bundle, not from the source checkout.

Codex plugin

From a local checkout of this repository:

codex plugin marketplace add /absolute/path/to/Graph-MCP --json
codex plugin add graph-mcp@personal --json

The Codex manifest launches ./dist/graph-mcp.js relative to the installed plugin root.

npm

Install the CLI globally:

npm install --global graph-mcp
graph-mcp setup

The graph-mcp executable starts the MCP server when invoked without arguments. Register that executable with your MCP host using its normal MCP-server configuration.

Source checkout

npm ci
npm run build
node dist/cli.js setup

Then register the built entrypoint with your host:

claude mcp add graph-mcp -- node /absolute/path/to/Graph-MCP/dist/cli.js
codex mcp add graph-mcp -- node /absolute/path/to/Graph-MCP/dist/cli.js

First-run setup and authentication

setup asks for the Entra application Client ID and Tenant ID and saves them to ~/.graph-mcp/config.json. The Client ID and Tenant ID are identifiers, not secrets. The setup command does not perform login.

For an installed plugin, use the bundled setup skill and its host-specific command:

Claude Code: node "${CLAUDE_PLUGIN_ROOT}/dist/graph-mcp.js" setup
Codex: resolve the installed plugin root from skills/setup/SKILL.md, change to that directory, then run node "./dist/graph-mcp.js" setup

After setup, call graph_auth_login. Browser PKCE login is the default and opens a local loopback callback on the configured redirect URI. If a browser or loopback callback is unavailable, call graph_auth_login with method: "device_code" and follow the returned Microsoft verification instructions.

Never paste a client secret, access token, refresh token, authorization code, MFA code, or other credentials into a conversation. Graph MCP does not need a client secret.

Configuration

For Client ID and Tenant ID, environment variables take precedence over ~/.graph-mcp/config.json, which takes precedence over built-in defaults. The setup command only persists those two identifiers. Other options are environment-only overrides of the built-in defaults.

Variable	Required	Default	Description
`AZURE_CLIENT_ID`	Yes	saved `azureClientId`, then empty	Entra public-client application ID
`AZURE_TENANT_ID`	No	saved `azureTenantId`, then `common`	Tenant ID or `common`
`GRAPH_REDIRECT_URI`	No	`http://localhost:3000/auth/callback`	Must exactly match the app registration
`GRAPH_TOKEN_ENCRYPTION_KEY`	No	generated local key	Explicit token-encryption key material
`GRAPH_TOKEN_REFRESH_BUFFER`	No	`300`	Refresh access tokens this many seconds before expiry
`GRAPH_RATE_LIMIT_MAX_REQUESTS`	No	`10000`	Sliding-window request limit
`GRAPH_RATE_LIMIT_WINDOW`	No	`600`	Sliding-window duration in seconds
`GRAPH_DEBUG`	No	`false`	Enable diagnostic logging on stderr

Positive integer options reject zero, negatives, decimals, and malformed values. Boolean values accept true, false, 1, 0, yes, no, on, or off.

Token storage and migration from Python

The Node server encrypts tokens with AES-256-GCM and stores them under ~/.graph-mcp:

tokens-v2.enc — encrypted token data
.key-v2 — generated local encryption key when no environment key is supplied

The previous Python runtime used tokens.enc and .key. Version 0.6.0 deliberately does not read, overwrite, or delete those legacy files because the ciphertext formats differ. After upgrading from the Python release, authenticate once with graph_auth_login; the Node server then creates its separate versioned token files. Existing Python token files remain untouched and may be removed later according to your local security policy.

Access tokens refresh automatically before expiry. graph_auth_logout clears the Node token state; it does not modify the legacy Python files.

Message and email formatting

The Teams message tools (graph_send_chat_message, graph_send_channel_message, and graph_reply_to_channel_message) and outbound mail tools (graph_send_mail and graph_reply_mail) default to HTML mode. When is_html=true, pass explicit HTML; Markdown is not converted automatically.

<p><strong>Status update</strong></p>
<ul>
  <li>Use <code>&lt;strong&gt;</code> for bold text.</li>
  <li>Use <code>&lt;pre&gt;&lt;code&gt;</code> for multi-line code blocks.</li>
</ul>

Use is_html=false for exact plain text. Mentions may use raw Graph data or this simplified shape, paired with the corresponding <at id="0">Jane Smith</at> tag in the HTML body:

[
  {
    "name": "Jane Smith",
    "user_id": "ef1c916a-3135-4417-ba27-8eb7bd084193"
  }
]

Development and verification

Install the locked dependencies and run the complete Node verification pipeline:

npm ci
npm run verify

Useful individual commands:

npm run format:check
npm run lint
npm run typecheck
npm test
npm run build
npm run validate:versions
npm run validate:package
npx vitest run tests/plugin-install-smoke.test.ts

Plugin and release validation:

claude plugin validate --strict plugins/graph-mcp
claude plugin validate --strict .
python3 "${CODEX_HOME:-$HOME/.codex}/skills/.system/plugin-creator/scripts/validate_plugin.py" plugins/graph-mcp
node scripts/test-plugin-install.mjs
npm pack --json --dry-run

The Codex validator is release tooling supplied by Codex's plugin-creator skill; Python is not required to build, test, or run Graph MCP itself. Before publishing, verify that package, Claude manifest, and Codex manifest versions are all 0.6.0, the committed plugin bundle is current, both installed plugins expose exactly 44 tools, and the working tree is clean.

Release procedure

Graph MCP 0.6.0 is released as an npm package. The obsolete Python/PyPI publishing workflow has been removed. Publish only from an approved release commit whose package version, both plugin manifest versions, changelog entry, and v0.6.0 tag agree.

Update the version in package.json, package-lock.json, and both plugin manifests, update CHANGELOG.md, and rebuild the committed plugin artifact.
Run the complete verification and plugin validation commands above from a clean checkout.
Inspect the exact npm payload and confirm the repository is clean:
```
npm pack --json --dry-run
git status --short
```
After the pull request is merged, create the v0.6.0 tag from the merged main commit and create the matching GitHub release. Configure npm authentication in the release environment or local user configuration. Never commit an npm token.
Publish the public package and verify the registry version:
```
npm publish --access public
npm view graph-mcp version
```

There is no Python/PyPI publishing step in the Node release. Any future GitHub Actions npm publishing workflow should run these same locked install, verification, validator, smoke, and publish commands from the protected version tag.

Architecture and runtime behavior

Claude Code or Codex  --stdio-->  Graph MCP  --HTTPS-->  Microsoft Graph API
                                      |
                                ~/.graph-mcp/
                                  config.json
                                  tokens-v2.enc
                                  .key-v2

Authentication uses OAuth 2.0 Authorization Code with PKCE or device code.
Access-token refresh is serialized so concurrent Graph calls share one refresh.
Graph requests use bounded timeouts, sliding-window rate limiting, and exponential retry behavior that honors Retry-After on throttled responses.
MCP protocol output is written to stdout; diagnostics are written to stderr.

Troubleshooting

Approval required during login

Confirm that the exact delegated permissions above are present and that required administrator consent has been granted.

403 Forbidden for one tool

The endpoint may need a delegated permission or administrator consent not available to the signed-in user. Check the tool's permission and your organizational policy.

Browser callback is unavailable

Call graph_auth_login with method: "device_code" and complete sign-in at the Microsoft verification URL.

Configuration changed but the host still uses old values

Restart the MCP server or host so the process reloads config.json and its environment. Environment variables override saved Client ID and Tenant ID values.

Upgraded from the Python release and appear logged out

This is expected once. Run graph_auth_login; the Node runtime creates tokens-v2.enc and .key-v2 without changing the old tokens.enc and .key files.

Disclaimer

This project is an independent open-source effort and is not affiliated with, endorsed by, or sponsored by Microsoft Corporation. Microsoft, Microsoft Teams, Outlook, Microsoft 365, Microsoft Graph, and Azure are trademarks of the Microsoft group of companies.

This software is provided "as is", without warranty of any kind. Use it at your own risk. The authors accept no liability for damages, data loss, or security issues arising from its use. You are responsible for complying with your organization's policies and Microsoft's API Terms of Use.

This software accesses Microsoft services on your behalf using your own credentials and app registration. Data retrieved from Microsoft Graph (including mail, messages, calendar events, meetings, and files) is passed to the model that invoked the tool. Follow BP and your organization's data-handling, retention, and acceptable-use requirements when using cloud-hosted AI models.

License

MIT — see LICENSE.

Graph MCP

Documentation

Graph MCP

What it does

Prerequisites

Install

Claude Code plugin

Codex plugin

npm

Source checkout

First-run setup and authentication

Configuration

Token storage and migration from Python

Message and email formatting

Development and verification

Release procedure

Architecture and runtime behavior

Troubleshooting

Disclaimer

License