Simple SMTP Mailer

MCP Tools

Send emails via SMTP using the msmtp command-line tool configured in ~/.msmtp/config for authentication and server settings.

Install

openclaw skills install simple-smtp-mail

Simple SMTP Mail

Send emails via SMTP using msmtp command-line tool.

Configuration

Create a configuration file at ~/.msmtp/config with the following format:

account default
host <SMTP_SERVER>
port <PORT>
tls on
tls_starttls off
auth on
user <EMAIL_ADDRESS>
password <PASSWORD>
from <EMAIL_ADDRESS>

Common SMTP Settings

Gmail:

SMTP Server: smtp.gmail.com
Port: 465 (SSL) or 587 (TLS)
Note: Use App Password, not your regular password

QQ Mail:

SMTP Server: smtp.qq.com
Port: 465

Outlook/Hotmail:

SMTP Server: smtp.office365.com
Port: 587

163.com:

SMTP Server: smtp.163.com
Port: 465

Installation

1. Install msmtp

macOS:

brew install msmtp

Linux (Debian/Ubuntu):

sudo apt install msmtp

Linux (Fedora/RHEL):

sudo dnf install msmtp

2. Configure SMTP

Edit ~/.msmtp/config:

nano ~/.msmtp/config

3. Set Permissions

chmod 600 ~/.msmtp/config

Sending Email

Basic Email

echo "Body text" | msmtp recipient@example.com

With Subject

echo -e "Subject: Your Subject\n\nBody text" | msmtp recipient@example.com

With Subject and From Header

echo -e "Subject: Your Subject\nFrom: your@email.com\n\nBody text" | msmtp recipient@example.com

HTML Content

echo -e "Subject: Your Subject\nContent-Type: text/html; charset=UTF-8\n\n<html>...</html>" | msmtp recipient@example.com

Testing

Check if SMTP server is reachable:

msmtp --file=~/.msmtp/config --serverinfo

Troubleshooting

"Account not found": Check your config file path with --file flag
"Authentication failed": Verify username and password (or App Password)
"Connection refused": Check port number and firewall settings
"TLS certificate error": Try tls_certcheck off in config (not recommended for production)