resend-email

name	resend-email
description	Enforces Head Shakers Resend email conventions when implementing email sending, templates, batch operations, and newsletter broadcasts. This skill ensures consistent patterns for email service methods, error handling, retry logic, and Sentry integration.

Resend Email Skill

Purpose

This skill enforces the Head Shakers Resend email conventions automatically during email implementation. It ensures consistent patterns for service architecture, email sending operations, template management, broadcast handling, error handling, and Sentry integration.

Activation

This skill activates when:

• Creating or modifying src/lib/services/resend*.ts files
• Working with email template files in src/lib/email-templates/
• Implementing email sending operations via Resend
• Creating broadcast or newsletter functionality
• Any code that imports from resend package
• Files containing email-related operations (send, batch, broadcast)

Workflow

1. Detect Resend email work (imports from resend or uses ResendService patterns)
2. Load references/Resend-Email-Conventions.md
3. Generate/modify code following all conventions
4. Scan for violations of email patterns
5. Auto-fix all violations (no permission needed)
6. Report fixes applied

Key Patterns

Service Architecture

• Use ResendService static class pattern
• Methods must have Async suffix for async operations
• Apply circuit breaker protection via circuitBreakers.externalService()
• Implement retry logic via withDatabaseRetry()
• Add Sentry breadcrumbs on success, capture exceptions on failure

Email Sending

Operation	Method	Limit
Single email	resend.emails.send()	1 per call
Batch emails	resend.batch.send()	Up to 100 per call
Broadcast	resend.broadcasts.create() + send()	Audience-based

Template Patterns

Type	Use Case	Location
Inline HTML	Simple confirmations, notifications	Private static methods
React Email	Complex newsletters, rich content	src/lib/email-templates/
Resend API Templates	Variable-based templates	Resend dashboard/API

Error Handling

• Return { failedEmails, sentCount } for bulk operations
• Return boolean for single operations
• Use level: 'warning' for non-critical failures
• Never fail entire operation for partial failures

Broadcasts & Audiences

• Always include {{{RESEND_UNSUBSCRIBE_URL}}} in broadcasts
• Use variable syntax: {{{VARIABLE|fallback}}}
• Support scheduled sending via scheduledAt parameter

Anti-Patterns to Avoid

1. Never include PII in Sentry context
2. Never skip circuit breaker protection
3. Never exceed 100 emails per batch call
4. Never hardcode email addresses
5. Never send broadcasts without unsubscribe link
6. Never use external CSS in email templates (inline only)
7. Never skip retry logic for email operations

Usage Pattern Reference

Use Case	Method	Skills Needed
Waitlist confirmation	sendWaitlistConfirmationAsync	resend-email
Welcome email	sendNewsletterWelcomeAsync	resend-email
Bulk notifications	sendLaunchNotificationsAsync	resend-email
Newsletter broadcast	sendBroadcastAsync	resend-email, sentry-monitoring
React template email	sendWithTemplateAsync	resend-email

References

• references/Resend-Email-Conventions.md - Complete Resend email conventions