Qasim Muhammad

Posted on Mar 23 • Originally published at cli.nylas.com

Send Email from the Command Line — No SMTP, No Sendmail, No Postfix

#cli #devops #linux #tutorial

Every CLI email tool has the same problem: SMTP configuration. mail needs Postfix. mutt needs credentials in a dotfile. msmtp handles sending but not reading. None support OAuth2 for Gmail or Microsoft 365 out of the box.

Nylas CLI bypasses all of this. Authenticate once, then send email from Linux, macOS, or Windows with one command. Works with Gmail, Outlook, Exchange, Yahoo, iCloud, and IMAP.

Install

# macOS / Linux
brew install nylas/nylas-cli/nylas

# Or shell script (macOS / Linux / WSL)
curl -fsSL https://cli.nylas.com/install.sh | bash

# Windows PowerShell
irm https://cli.nylas.com/install.ps1 | iex

Authenticate

nylas auth config
# Paste your API key

nylas auth whoami
# => Authenticated as you@company.com (Google Workspace)

Send an email

nylas email send \
  --to "colleague@company.com" \
  --subject "Quarterly report" \
  --body "Please review the Q4 numbers before Friday."

# Skip confirmation prompt
nylas email send --to user@example.com --subject "Quick note" --body "..." --yes

# CC and BCC
nylas email send \
  --to alice@team.com \
  --cc bob@team.com \
  --bcc manager@team.com \
  --subject "Sprint update" \
  --body "All tasks on track."

Read and search your inbox

# List recent emails
nylas email list --limit 10

# Only unread
nylas email list --unread

# Search by keyword
nylas email search "invoice" --limit 5

# Read a specific message
nylas email read msg_abc123

Schedule emails for later

# Send in 2 hours
nylas email send --to team@company.com --subject "Reminder" --body "..." --schedule 2h

# Send tomorrow morning
nylas email send --to team@company.com --subject "Standup" --body "..." --schedule "tomorrow 9am"

GPG sign and encrypt

# Sign with your key
nylas email send --to legal@partner.com --subject "Contract" --body "..." --sign

# Encrypt with recipient's public key
nylas email send --to legal@partner.com --subject "Contract" --body "..." --encrypt

# Both
nylas email send --to legal@partner.com --subject "Contract" --body "..." --sign --encrypt

Full GPG guide: GPG Encrypted Email from the CLI

AI-powered smart compose

# Generate a draft from a prompt
nylas email smart-compose --prompt "Thank them for the meeting and confirm next steps"

# Reply to a specific message
nylas email smart-compose --message-id msg_abc123 --prompt "Accept the invitation politely"

Scripting with JSON output

Every command supports --json for piping into jq or other tools:

# Unread count
nylas email list --unread --json | jq length

# Extract senders from recent messages
nylas email list --limit 20 --json | jq -r '.[].from[0].email'

# Bulk send from CSV
while IFS=, read -r email name; do
  nylas email send \
    --to "$email" \
    --subject "Hello $name" \
    --body "Your account is ready." \
    --yes
  sleep 2
done < contacts.csv

How it compares

Feature	mail / mailx	mutt	Nylas CLI
Send email	Needs MTA	Needs SMTP	One command
Read inbox	Local only	Yes	Yes
Gmail OAuth2	No	Complex	Built-in
Microsoft 365	No	Complex	Built-in
GPG sign/encrypt	Manual	Built-in	Built-in
Calendar access	No	No	Yes
JSON output	No	No	`--json`
AI compose	No	No	Yes
MCP server	No	No	Built-in

Give AI agents email access

The CLI includes a built-in MCP server. One command gives Claude Code, Cursor, or Codex CLI full email and calendar tools:

nylas mcp install --assistant claude-code

Full setup: Give Your AI Coding Agent an Email Address

Full guide with tracking, attachments, and scheduling examples: Send Email from the Command Line

More guides: cli.nylas.com/guides

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