Send SMTP Email

Use this skill when the task is to send a simple email through SMTP with a mailbox account.

Embedded SMTP Config

If the runtime environment does not support .env, use the following embedded configuration block.

The sending script can fall back to this block when the env file is missing.

# Provider preset: 126, qq, sina, aliyun, custom
EMAIL_PROVIDER=126

# If EMAIL_PROVIDER=custom, fill these yourself.
SMTP_HOST=smtp.126.com
SMTP_PORT=465

# true for SMTPS on port 465, false for STARTTLS on port 587.
SMTP_USE_SSL=true

# Usually the mailbox address.
SMTP_USERNAME=your_email_username

# 126 / QQ commonly use an SMTP authorization code here.
# Sina / Aliyun may use the mailbox password depending on account settings.
SMTP_PASSWORD=your_smtp_secret

FROM_EMAIL=your_email_username
FROM_NAME=your_name

# Seconds
SMTP_TIMEOUT=30

Trigger Cues

Use this skill when the user asks for any of the following:

• send a one-off test email through SMTP
• configure .env for a mailbox account such as 126, qq, sina, or aliyun
• scaffold a reusable SMTP email sender
• debug SMTP host, port, SSL, login, or authorization-code issues

Supported Providers

Built-in presets are available for:

• 126
• qq
• sina
• aliyun
• custom

See references/providers.md for preset host and authentication notes.

Workflow

1. Read .env from the repo root. If it does not exist, fall back to the embedded config block in this file.
2. Resolve provider defaults for 126, qq, sina, or aliyun. If the provider is not listed, require SMTP_HOST and SMTP_PORT.
3. Read the message inputs from the user request: recipient, subject, and body.
4. Prefer scripts/send_email.py --dry-run first when validating configuration.
5. Run scripts/send_email.py with runtime message arguments once the sender, recipient, and secret are confirmed.

Default Behavior

• SMTP_USERNAME defaults to FROM_EMAIL when left empty.
• SMTP_USE_SSL=true means SMTPS, typically on port 465.
• SMTP_USE_SSL=false means SMTP with STARTTLS, typically on port 587.
• SMTP_PASSWORD is treated as the one secret field, whether the provider expects an authorization code or the mailbox password.

Safety Rules

• Never print the full value of SMTP_PASSWORD.
• Treat SMTP_PASSWORD as either an SMTP authorization code or the mailbox password, depending on provider policy.
• Before a real send, make sure FROM_EMAIL and TO_EMAIL are not placeholder values unless the user explicitly wants a dry run.
• In normal SMTP usage, keep FROM_EMAIL aligned with the authenticated mailbox unless the provider supports aliases.
• Prefer a single test message before attempting repeated sends.

Required Inputs

• EMAIL_PROVIDER
• SMTP_PASSWORD
• FROM_EMAIL
• recipient email
• subject
• body

Optional Inputs

• SMTP_HOST
• SMTP_PORT
• SMTP_USE_SSL
• SMTP_USERNAME
• FROM_NAME
• SMTP_TIMEOUT

Minimal .env Contract

For preset providers, the minimum practical configuration is:

EMAIL_PROVIDER=qq
SMTP_PASSWORD=your_smtp_secret
FROM_EMAIL=your_email@qq.com

For custom, also set:

• SMTP_HOST
• SMTP_PORT
• SMTP_USE_SSL

Common Commands

Validate config without sending:

python scripts/send_email.py --to-email someone@example.com --email-subject "Test" --email-body "Hello" --dry-run

Send a real email:

python scripts/send_email.py --to-email someone@example.com --email-subject "Test" --email-body "Hello"

Use a different env file:

python scripts/send_email.py --env-file .tmp-send.env --to-email someone@example.com --email-subject "Test" --email-body "Hello"

Failure Handling

• Authentication error: verify whether the provider expects an authorization code instead of the normal mailbox password.
• Connection or timeout error: verify host, port, SSL mode, and whether the mailbox enabled SMTP.
• Sender rejected: make FROM_EMAIL match the authenticated mailbox unless the provider explicitly supports aliases.
• Custom provider: set SMTP_HOST, SMTP_PORT, and SMTP_USE_SSL explicitly in .env.

Example Requests

• "Send a test email to someone@example.com through QQ SMTP."
• "给 xxx@xxx.com 发一个主题为 xxx 内容为 xxx 的邮件。"
• "Set up .env for 126 mailbox SMTP."
• "Why does my SMTP login pass but the server rejects the sender address?"

Resources

• Provider notes: references/providers.md
• Sending script: scripts/send_email.py