0n3
MCP servers · Microsoft 365 · MCP server

Connect Codex CLI to Microsoft 365

One line gives Codex CLI your Microsoft 365 account as tools: 20 endpoints, mail, events, teams, called with your own connection. No key in the prompt, a receipt for every call, revoke Codex CLI's access alone any time.

Get the line for Codex CLIConnect Microsoft 365 first

Three steps

  1. Create a free 0n3 account and connect Microsoft 365. Paste a key or sign in; it lands in your vault, encrypted.
  2. Install 0n3 into Codex CLI. OpenAI's terminal agent reads 0n3 over Streamable HTTP with a token from your environment.
  3. Ask Codex CLI: whoami. Then: "Send a mail in Microsoft 365".
Put the token in your environment
export ON3_TOKEN="<your 0n token>"

Add it to your shell profile so Codex finds it next time.

The line above carries a placeholder; 0n3.app/install mints a real key named for Codex CLI and fills it in.

What Codex CLI can then do in Microsoft 365

Mail · Send and manage Outlook email1
Send a mailPOST /me/sendMail
Events · Manage Outlook calendar events4
List eventsGET /me/events
Create an eventPOST /me/events
Update an eventPATCH /me/events/{eventId}
Delete an eventDELETE /me/events/{eventId}
Teams · Send Teams messages and list channels3
List teamsGET /me/joinedTeams
List channelsGET /teams/{teamId}/channels
Send a channel messagePOST /teams/{teamId}/channels/{channelId}/messages
Users · View organization users1
Get an userGET /me
Files · OneDrive and SharePoint files, including items shared by link from another user's drive0
OneDrive and SharePoint files, including items shared by link from another user's drive
More · Everything else this app exposes.11
List messagesGET /me/messages
Get a messageGET /me/messages/{messageId}
Delete a messageDELETE /me/messages/{messageId}
List drive itemsGET /me/drive/root/children
Get a drive itemGET /me/drive/items/{itemId}
Search driveGET /me/drive/root/search(q='{query}')
Resolve shareGET /shares/{encodedUrl}/driveItem
List shared with meGET /me/drive/sharedWithMe
Get an item contentGET /drives/{driveId}/items/{itemId}/content
Get a siteGET /sites/{hostname}:/sites/{sitePath}
List site itemsGET /sites/{siteId}/drive/root/children

Microsoft 365 in other AI clients

Claude Code + Microsoft 365MCP server + skillClaude (desktop & claude.ai) + Microsoft 365connectorChatGPT + Microsoft 365connector · GPT actionGemini CLI + Microsoft 365MCP serverCursor + Microsoft 365MCP serverVS Code (Copilot) + Microsoft 365MCP serverWindsurf + Microsoft 365MCP server

Codex CLI with other apps

Hostinger363 endpointsTelegram132 endpointsPipedrive95 endpointsResend67 endpointsSquare57 endpointsLinkedIn50 endpointsSlack45 endpointsFigma32 endpointsCloudConvert32 endpointseBay25 endpointsQuickBooks21 endpointsCloudflare21 endpoints