Email, calendar, and contacts from your terminal.
Pipe-friendly, headless-first. Give any agent email, calendar, and contacts in one command.
Nylas CLI is a free, open-source command-line tool that provides unified access to email, calendar, and contacts across Gmail, Microsoft 365, Exchange, Yahoo, iCloud, and IMAP providers. It includes a built-in MCP server for AI agents, GPG encryption, webhook management, and 72+ commands for scripting and automation.
Features
Agent-native
Built-in MCP server lets Claude, Cursor, and VS Code read and send email in one command. Typed tools across email, calendar, and contacts — no API keys or middleware required.
Runs anywhere
Works over SSH, inside containers, and in CI pipelines. No GUI, no browser, no display server. Pipe JSON output to jq, scripts, or other CLI tools.
Unified email
One interface for Gmail, Outlook, Exchange, Yahoo, iCloud, and any IMAP server. Send, search, list, and read email across 6 providers with a single command.
Calendar
List, create, update, and delete events. AI scheduling with natural language, DST-aware timezone handling, and free/busy availability checks.
Contacts
Search and sync contacts across every connected provider. List contact groups, look up by name or email, and export as JSON for automation.
Sandboxed
OAuth tokens stored in your OS keyring. GPG signing and encryption keep messages private. Your credentials and keys never leave your machine.
Guides
Learn by doing
Microsoft Graph Mail Query Filters
Microsoft Graph mail query guide: $filter (OData) vs $search (KQL) on /me/messages, why you cannot combine them, plus $select, $top, paging, and a CLI shortcut.
Microsoft Graph Mail Folders API
List Microsoft Graph mail folders, address well-known folder names, walk child folders, read item and unread counts, and filter on displayName by terminal.
Microsoft Graph Change Notifications
Microsoft Graph change notifications for mail and calendar: the subscription lifecycle, the validation token handshake, the 7-day expiry, and renewal.
Gmail API: Send Raw MIME Messages
Build and send raw RFC 5322 messages with the Gmail API: base64url encode the MIME, set required headers, thread replies, and skip the work with the Nylas CLI.
Google Calendar API Error Codes
A reference for the Google Calendar API errors developers hit most: 403 rate limits, 410 fullSyncRequired, 412, 429 and 401. What each means and how to fix it.
Google Calendar API Free/Busy Query
Query the Google Calendar API freeBusy endpoint for busy intervals. See freebusy.query vs events.list, then check availability across providers from the CLI.
Install
One install. Then pipe it to anything.
brew install nylas/nylas-cli/nylasThen run guided setup
nylas initSigns you up, creates an app and API key, and connects your email in one flow.
Prefer manual setup? Already have an API key? Log in with nylas auth config.