Audits email domain deliverability setup (SPF, DKIM, DMARC, MX records, blacklists, TLS) and generates health score (0-100) with prioritized fix list. Checks bulk sender compliance against Google/Yahoo/Microsoft 2024-2026 requirements. Provides DNS records to add/update. Use when user asks to audit, check, or analyze email deliverability, domain health, or inbox placement.
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Audits email domain deliverability setup (SPF, DKIM, DMARC, MX records, blacklists, TLS) and generates health score (0-100) with prioritized fix list. Checks bulk sender compliance against Google/Yahoo/Microsoft 2024-2026 requirements. Provides DNS records to add/update. Use when user asks to audit, check, or analyze email deliverability, domain health, or inbox placement.
user-invocable
false
allowed-tools
["Read","Bash","Grep","Glob"]
Email Audit Sub-Skill
Purpose
Performs comprehensive email deliverability auditing for a domain. Checks DNS authentication records (SPF, DKIM, DMARC), infrastructure (MX, PTR, TLS), reputation (blacklists), and bulk sender compliance. Generates a health score (0-100) with prioritized fixes.
Note: This may require network access. If not available, note as "Unable to verify".
Scoring:
TLS 1.2+ with STARTTLS: 100 points
TLS 1.0/1.1 with STARTTLS: 60 points
No STARTTLS: 0 points
7. Blacklist Check (Weight: 20%)
What to check:
Domain and MX IP addresses against major blacklists:
Spamhaus (SBL, XBL, PBL)
Barracuda
SORBS
SpamCop
URIBL
Invaluement
Commands:
# Use checkdmarc library if available
python -c "import checkdmarc; print(checkdmarc.check_domains(['<domain>']))"# Or manual checks
dig <ip>.zen.spamhaus.org +short
dig <ip>.b.barracudacentral.org +short
Scoring:
Clean on all lists: 100 points
Listed on 1 minor list: 50 points
Listed on 1 major list (Spamhaus, Barracuda): 30 points
Listed on 2+ major lists: 0 points
Critical: Any listing on major blacklists severely impacts deliverability.
8. Bulk Sender Compliance (Weight: 10%)
Applies to: Domains sending 5,000+ emails/day to Gmail, Yahoo, Microsoft recipients.
Spawn these agents in parallel for faster auditing:
Agent 1: email-deliverability
Check DNS authentication records for <domain>:
- SPF record validation
- DKIM record discovery (selectors: google, default, selector1, selector2, k1)
- DMARC policy analysis
- MX record validation
- PTR/reverse DNS check
Return JSON with pass/fail status and raw records.
Agent 2: email-compliance
Check bulk sender compliance for <domain>:
- Verify both SPF and DKIM pass
- Check DMARC alignment
- Note TLS support
- Check for List-Unsubscribe headers (if sample email provided)
Return compliance checklist with met/not met status.
Agent 3: email-reputation (if tools available)
Check reputation for <domain>:
- Blacklist status (Spamhaus, Barracuda, SORBS, SpamCop)
- Historical deliverability issues
- Spam complaint rate (if available)
Return list of blacklist hits and reputation score.
Step 3: Aggregate Results
Collect results from all agents and calculate weighted health score.
Step 4: Generate Prioritized Fix List
Categorize issues by priority:
Critical (Fix Immediately):
Blacklist listings
Missing SPF/DKIM/DMARC
Invalid DNS records
MX records not resolving
High (Fix Within 1 Week):
Weak SPF enforcement (~all instead of -all)
1024-bit DKIM keys (upgrade to 2048-bit)
DMARC policy p=none (upgrade to p=quarantine or p=reject)
Missing PTR records
Medium (Fix Within 1 Month):
Missing aggregate reporting (rua tag)
No TLS/STARTTLS support
SPF approaching 10 DNS lookup limit
Missing bonus features (BIMI, MTA-STS, TLSRPT)
Step 5: Generate DNS Record Recommendations
Provide exact DNS records to add/update with copy-paste ready values.
Output Format
Structure the audit report as:
Header: ## Email Deliverability Audit: [domain] with date, health score, rating
Authentication table: SPF/DKIM/DMARC with status, score, raw records
Infrastructure table: MX/PTR/TLS with status, score, provider detection
Reputation: Blacklist status across Spamhaus, Barracuda, SORBS, SpamCop
