email

name	email
description	Send emails via Resend, Mailgun, or SendGrid using your own API credentials. Auto-detects available provider. Use for reports, alerts, client communications, and business emails.
version	1.0.0
allowed-tools	Bash
metadata	{"credentials":["RESEND_API_KEY (Resend)","EMAIL_FROM (Resend/SendGrid sender)","MAILGUN_API_KEY (Mailgun)","MAILGUN_DOMAIN (Mailgun)","SENDGRID_API_KEY (SendGrid)"]}

Email Skill

Send emails to any recipient using your own email provider credentials.

Quick Start

# Resend (simplest — 1 curl call)
curl -X POST https://api.resend.com/emails \
  -H "Authorization: Bearer $RESEND_API_KEY" \
  -H "Content-Type: application/json" \
  -d "{\"from\":\"$EMAIL_FROM\",\"to\":\"[e-mail]\",\"subject\":\"Hello\",\"text\":\"Your message\"}"

Provider Detection

Check which credentials are available and use that provider:

if [ -n "$RESEND_API_KEY" ]; then
  echo "Provider: Resend"
elif [ -n "$MAILGUN_API_KEY" ]; then
  echo "Provider: Mailgun"
elif [ -n "$SENDGRID_API_KEY" ]; then
  echo "Provider: SendGrid"
else
  echo "ERROR: No email credentials configured."
  echo "Set one of: RESEND_API_KEY, MAILGUN_API_KEY, or SENDGRID_API_KEY"
  exit 1
fi

Prerequisites

At least one provider's credentials must be configured as Space environment variables.

Provider	Required Variables	Free Tier
Resend (recommended)	RESEND_API_KEY, EMAIL_FROM	3,000 emails/month
Mailgun	MAILGUN_API_KEY, MAILGUN_DOMAIN	1,000 emails/month (trial)
SendGrid	SENDGRID_API_KEY, EMAIL_FROM	100 emails/day

Verify Setup

echo "Resend: ${RESEND_API_KEY:+configured}"
echo "Mailgun: ${MAILGUN_API_KEY:+configured}"
echo "SendGrid: ${SENDGRID_API_KEY:+configured}"
echo "From: ${EMAIL_FROM:-not set}"

Resend Recipes

Resend has the simplest API — recommended for new users.

Send Plain Text Email

curl -s -X POST https://api.resend.com/emails \
  -H "Authorization: Bearer $RESEND_API_KEY" \
  -H "Content-Type: application/json" \
  -d "{
    \"from\": \"$EMAIL_FROM\",
    \"to\": \"[e-mail]\",
    \"subject\": \"Your Subject\",
    \"text\": \"Plain text message body\"
  }"

Send HTML Email

curl -s -X POST https://api.resend.com/emails \
  -H "Authorization: Bearer $RESEND_API_KEY" \
  -H "Content-Type: application/json" \
  -d "{
    \"from\": \"$EMAIL_FROM\",
    \"to\": \"[e-mail]\",
    \"subject\": \"Weekly Report\",
    \"html\": \"<h1>Report</h1><p>Your HTML content here</p>\"
  }"

Send to Multiple Recipients

curl -s -X POST https://api.resend.com/emails \
  -H "Authorization: Bearer $RESEND_API_KEY" \
  -H "Content-Type: application/json" \
  -d "{
    \"from\": \"$EMAIL_FROM\",
    \"to\": [\"[e-mail]\", \"[e-mail]\"],
    \"cc\": [\"[e-mail]\"],
    \"subject\": \"Team Update\",
    \"text\": \"Message to the team\"
  }"

Mailgun Recipes

Battle-tested provider, more complex API but very reliable.

Send Email via Mailgun

# Determine API endpoint (US or EU region)
if [ "$MAILGUN_REGION" = "EU" ]; then
  MAILGUN_API="https://api.eu.mailgun.net"
else
  MAILGUN_API="https://api.mailgun.net"
fi

curl -s --user "api:${MAILGUN_API_KEY}" \
  "${MAILGUN_API}/v3/${MAILGUN_DOMAIN}/messages" \
  -F from="${MAILGUN_FROM_EMAIL:-noreply@${MAILGUN_DOMAIN}}" \
  -F to="[e-mail]" \
  -F subject="Your Subject" \
  -F text="Plain text message"

Send HTML via Mailgun

if [ "$MAILGUN_REGION" = "EU" ]; then
  MAILGUN_API="https://api.eu.mailgun.net"
else
  MAILGUN_API="https://api.mailgun.net"
fi

curl -s --user "api:${MAILGUN_API_KEY}" \
  "${MAILGUN_API}/v3/${MAILGUN_DOMAIN}/messages" \
  -F from="${MAILGUN_FROM_EMAIL:-noreply@${MAILGUN_DOMAIN}}" \
  -F to="[e-mail]" \
  -F subject="Report" \
  --form-string html="<h1>Report</h1><p>Your HTML content</p>"

SendGrid Recipes

Enterprise-standard email provider.

Send Email via SendGrid

curl -s -X POST https://api.sendgrid.com/v3/mail/send \
  -H "Authorization: Bearer $SENDGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d "{
    \"personalizations\": [{\"to\": [{\"email\": \"[e-mail]\"}]}],
    \"from\": {\"email\": \"$EMAIL_FROM\"},
    \"subject\": \"Your Subject\",
    \"content\": [{\"type\": \"text/plain\", \"value\": \"Message body\"}]
  }"

Send HTML via SendGrid

curl -s -X POST https://api.sendgrid.com/v3/mail/send \
  -H "Authorization: Bearer $SENDGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d "{
    \"personalizations\": [{\"to\": [{\"email\": \"[e-mail]\"}]}],
    \"from\": {\"email\": \"$EMAIL_FROM\"},
    \"subject\": \"Report\",
    \"content\": [{\"type\": \"text/html\", \"value\": \"<h1>Report</h1><p>Your content</p>\"}]
  }"

Email Templates

Report Delivery

SUBJECT="[Report] ${REPORT_NAME} — $(date +%Y-%m-%d)"
BODY="Hi,

Your report '${REPORT_NAME}' is ready.

Summary:
${REPORT_SUMMARY}

The full report is attached to this Space at: ${REPORT_PATH}

— Your TeamDay Agent"

Error Alert

SUBJECT="[Alert] ${SERVICE_NAME} — Action Required"
BODY="An issue was detected that requires your attention.

Service: ${SERVICE_NAME}
Error: ${ERROR_MESSAGE}
Time: $(date -u +"%Y-%m-%d %H:%M:%S UTC")

Recommended action:
${RECOMMENDED_ACTION}

— Your TeamDay Agent"

Weekly Summary

SUBJECT="[Weekly Summary] $(date +%Y-%m-%d)"
BODY="Here's your weekly summary:

${SUMMARY_CONTENT}

Key metrics:
${KEY_METRICS}

— Your TeamDay Agent"

Error Handling

Always check the HTTP response:

RESPONSE=$(curl -s -w "\n%{http_code}" -X POST https://api.resend.com/emails \
  -H "Authorization: Bearer $RESEND_API_KEY" \
  -H "Content-Type: application/json" \
  -d "{\"from\":\"$EMAIL_FROM\",\"to\":\"[e-mail]\",\"subject\":\"Test\",\"text\":\"Test\"}")

HTTP_CODE=$(echo "$RESPONSE" | tail -n1)
BODY=$(echo "$RESPONSE" | sed '$d')

if [ "$HTTP_CODE" -ge 200 ] && [ "$HTTP_CODE" -lt 300 ]; then
  echo "Email sent successfully"
else
  echo "Failed to send email (HTTP $HTTP_CODE): $BODY"
fi

Common Errors

Error	Provider	Cause	Solution
401/403	All	Invalid API key	Check credentials in Space env vars
422	Resend	Invalid from address	Verify domain in Resend dashboard
400	Mailgun	Domain not verified	Complete DNS verification
403	SendGrid	Sender not verified	Verify sender identity in SendGrid

Provider Setup Guides

Resend (Recommended)

1. Sign up at resend.com
2. Add and verify your domain (or use [e-mail] for testing)
3. Create an API key — set as RESEND_API_KEY
4. Set EMAIL_FROM to your verified sender (e.g., [e-mail])

Mailgun

1. Sign up at mailgun.com
2. Add and verify your sending domain
3. Get API key from Settings — API Keys — set as MAILGUN_API_KEY
4. Set MAILGUN_DOMAIN to your verified domain

SendGrid

1. Sign up at sendgrid.com
2. Verify a sender identity
3. Create an API key with "Mail Send" permissions — set as SENDGRID_API_KEY
4. Set EMAIL_FROM to your verified sender

Security Note

This skill sends emails using YOUR provider credentials to ANY recipient. You are responsible for:

• Email content and reputation
• Compliance with anti-spam laws (CAN-SPAM, GDPR)
• Managing your sending domain's reputation

For notifications sent only to yourself, use the notify-user skill instead (uses TeamDay-managed credentials).

Tips

• Start with Resend — simplest API, generous free tier
• Use templates — consistent formatting improves deliverability
• Check response codes — don't assume success
• Plain text fallback — always include a text version alongside HTML
• Rate limiting — space out bulk sends to avoid provider limits