email-deliverability

Email Deliverability: Audit, Diagnosis & Fix

Your Setup — Fill These In for Better Results

This skill gives generic advice by default. Fill in your details below and it will skip triage and go straight to auditing or diagnosing your specific deliverability situation.

• Sending domain(s): [e.g., mail.yourcompany.com]
• ESP / sending platform: [e.g., SendX, Mailchimp, custom MTA]
• Monthly send volume: [e.g., 500,000]
• IP type: [shared / dedicated / mixed]
• Domain age: [e.g., 3 years]
• Current open rate by provider: [e.g., Gmail 22%, Microsoft 18%, Yahoo 25%]
• Current bounce rate: [e.g., 0.8%]
• Current complaint rate: [e.g., 0.05%]
• Recent changes: [e.g., migrated ESPs last month, added new IP, none]

This skill captures the SendPost Way — a diagnostic methodology built from managing IP pools processing 10-18 million messages daily and consulting for ESPs handling billions of emails. The approach is systematic, data-driven, and built on a core belief: 95-99% of deliverability problems can be solved through four pillars at the ESP/send-engine level.

How to Use This Skill

Two modes. Pick based on what the person is asking for:

Audit mode — they want a proactive review ("audit my email setup", "we're launching, what do we need to get right?", "check my deliverability"). Run the Audit Checklist below, report findings by severity, and end with a prioritized fix list.

Diagnose & fix mode — something is actively broken ("emails going to spam", "open rates dropped", "we got blocklisted"). Follow the SendPost Way in order:

1. Triage — Classify the problem type (see Triage section)
2. Diagnose — Walk through the Four Pillars framework
3. Recommend — Provide a specific fix plan with timeline
4. Monitor — Define what to watch during recovery

Either way: be direct, be honest about what's broken, and focus on root causes rather than symptoms. If the data shows something is bad, say so clearly. And keep the language plain. "Your SPF record has too many DNS lookups" beats "You've exceeded the RFC 7208 specification limit for mechanism evaluations."