Validation Checks

Spamidate performs up to 18 validation checks on each email. This document explains what each check does and how to interpret results.

Check Response Structure

Every check returns a consistent structure:

{
  "check": "syntax",
  "passed": true,
  "status": "pass",
  "category": "syntax",
  "reason": "Email syntax is valid (RFC 5322 compliant)",
  "action": "allow",
  "confidence": 100,
  "metadata": {}
}

Field	Description
`check`	Check identifier
`passed`	Whether this check passed
`status`	`pass`, `fail`, `warn`, `skip`, or `error`
`category`	Grouping: syntax, domain, mailbox, reputation, quality, security
`reason`	Human-readable explanation
`action`	Recommended: `allow`, `block`, `flag`, `review`
`confidence`	Certainty level (0-100)
`metadata`	Additional check-specific data

Status Values

Status	Meaning	Score Impact
`pass`	No issues found	Neutral/positive
`fail`	Blocking issue	Negative
`warn`	Concern, not blocking	Minor negative
`skip`	Check skipped	None
`error`	Check failed	None

Core Checks (All Tiers)

syntax

All Tiers

Validates email format against RFC 5322.

Checks:

Valid local part (before @)
Valid domain part (after @)
Allowed characters
Length limits (local: 64, domain: 255, total: 254)
No consecutive/leading/trailing dots

{
  "check": "syntax",
  "passed": true,
  "status": "pass",
  "category": "syntax",
  "reason": "Email syntax is valid (RFC 5322 compliant)",
  "confidence": 100
}

domain

All Tiers

Verifies the domain exists via DNS lookup.

{
  "check": "domain",
  "passed": true,
  "status": "pass",
  "category": "domain",
  "reason": "Domain exists and resolves",
  "confidence": 100,
  "metadata": {
    "hasA": true,
    "hasAAAA": true
  }
}

mxRecords

All Tiers

Checks for valid MX (Mail Exchange) records.

{
  "check": "mxRecords",
  "passed": true,
  "status": "pass",
  "category": "domain",
  "reason": "Found 5 MX records",
  "confidence": 100,
  "metadata": {
    "mxRecords": ["mx1.example.com", "mx2.example.com"],
    "primaryMx": "mx1.example.com",
    "mxCount": 5
  }
}

disposable

All Tiers

Detects temporary/disposable email providers.

{
  "check": "disposable",
  "passed": false,
  "status": "fail",
  "category": "reputation",
  "reason": "Disposable email provider detected (mailinator.com)",
  "action": "block",
  "confidence": 99,
  "metadata": {
    "provider": "mailinator.com",
    "isDisposable": true
  }
}

Common providers detected: mailinator.com, tempmail.com, guerrillamail.com, 10minutemail.com

roleBased

All Tiers

Identifies role-based/generic addresses (info@, support@, admin@).

Risk Levels:

Level	Examples	Recommendation
`high`	abuse@, postmaster@, noreply@	Block for marketing
`medium`	info@, support@, sales@	Use with caution
`low`	contact@, hello@	Generally OK

{
  "check": "roleBased",
  "passed": false,
  "status": "warn",
  "category": "quality",
  "reason": "Role-based email address (support@)",
  "action": "flag",
  "confidence": 95,
  "metadata": {
    "isRoleBased": true,
    "roleType": "support",
    "riskLevel": "medium"
  }
}

catchAll

All Tiers

Detects catch-all domains that accept any address.

{
  "check": "catchAll",
  "passed": false,
  "status": "warn",
  "category": "quality",
  "reason": "Domain accepts all email addresses (catch-all)",
  "action": "flag",
  "confidence": 85,
  "metadata": {
    "isCatchAll": true
  }
}

typoSuggestion

Hobby+

Detects common typos and suggests corrections.

{
  "check": "typoSuggestion",
  "passed": false,
  "status": "warn",
  "category": "quality",
  "reason": "Possible typo detected: gmial.com → gmail.com",
  "action": "review",
  "confidence": 95,
  "metadata": {
    "hasTypo": true,
    "originalDomain": "gmial.com",
    "suggestion": "gmail.com"
  }
}

Common corrections:

gmial.com → gmail.com
hotmal.com → hotmail.com
yaho.com → yahoo.com
outloo.com → outlook.com

freeEmail

Hobby+

Identifies free email providers (Gmail, Yahoo, Outlook).

{
  "check": "freeEmail",
  "passed": true,
  "status": "warn",
  "category": "quality",
  "reason": "Free email provider (gmail.com)",
  "action": "allow",
  "confidence": 100,
  "metadata": {
    "isFreeEmail": true,
    "provider": "Google",
    "providerName": "Gmail"
  }
}

Advanced Checks (Pro+)

spamTrap

Pro+

Detects known and suspected spam trap addresses.

Risk Level	Description	Action
`critical`	Confirmed spam trap	Block
`high`	Likely spam trap	Avoid
`medium`	Possible spam trap	Caution
`safe`	No indicators	Allow

{
  "check": "spamTrap",
  "passed": false,
  "status": "fail",
  "category": "reputation",
  "reason": "High probability spam trap detected",
  "action": "block",
  "confidence": 88,
  "metadata": {
    "isSpamTrap": true,
    "riskLevel": "high",
    "indicators": ["recycled-domain", "honeypot-pattern"]
  }
}

emailAuthentication

Pro+

Checks domain email authentication (SPF, DKIM, DMARC).

{
  "check": "emailAuthentication",
  "passed": true,
  "status": "pass",
  "category": "security",
  "reason": "Strong email authentication (SPF + DKIM + DMARC)",
  "confidence": 95,
  "metadata": {
    "spf": { "exists": true, "policy": "-all" },
    "dkim": { "exists": true },
    "dmarc": { "exists": true, "policy": "reject" }
  }
}

blacklist

Pro+

Checks domain against email blacklists.

{
  "check": "blacklist",
  "passed": false,
  "status": "fail",
  "category": "reputation",
  "reason": "Domain found on 3 blacklists",
  "action": "block",
  "confidence": 92,
  "metadata": {
    "isBlacklisted": true,
    "totalListed": 3,
    "riskScore": 75
  }
}

domainTrust

Pro+

Evaluates overall domain trustworthiness.

Factors: Domain age, SSL certificate, WHOIS privacy, historical reputation

{
  "check": "domainTrust",
  "passed": true,
  "status": "pass",
  "category": "security",
  "reason": "High trust domain (established, valid SSL)",
  "confidence": 88,
  "metadata": {
    "trustLevel": "high",
    "domainAge": 3650,
    "hasSSL": true
  }
}

fraudDetection

Pro+

AI-powered fraud pattern detection.

{
  "check": "fraudDetection",
  "passed": false,
  "status": "fail",
  "category": "security",
  "reason": "Multiple fraud indicators detected",
  "action": "block",
  "confidence": 82,
  "metadata": {
    "fraudScore": 75,
    "riskLevel": "high",
    "patterns": [
      { "pattern": "keyboard-walk", "severity": "medium" },
      { "pattern": "suspicious-tld", "severity": "high" }
    ]
  }
}

Enterprise Checks

smtpVerification

Business+

Direct SMTP mailbox verification.

{
  "check": "smtpVerification",
  "passed": true,
  "status": "pass",
  "category": "mailbox",
  "reason": "Mailbox exists and accepts mail",
  "confidence": 90,
  "metadata": {
    "mailboxExists": true,
    "isGreylisted": false
  }
}

corporateEmail

Growth+

Identifies corporate/business email domains.

{
  "check": "corporateEmail",
  "passed": true,
  "status": "pass",
  "category": "quality",
  "reason": "Corporate email domain (Microsoft 365)",
  "confidence": 95,
  "metadata": {
    "isCorporate": true,
    "provider": "microsoft365",
    "companyDomain": "acme.com"
  }
}

mailboxProvider

Growth+

Identifies the email infrastructure provider.

{
  "check": "mailboxProvider",
  "passed": true,
  "status": "pass",
  "category": "quality",
  "reason": "Google Workspace detected",
  "confidence": 98,
  "metadata": {
    "provider": "Google Workspace",
    "infrastructure": "google_workspace"
  }
}

Check Availability by Tier

Check	Free	Hobby	Growth	Pro	Business	Enterprise
syntax	✓	✓	✓	✓	✓	✓
domain	✓	✓	✓	✓	✓	✓
mxRecords	✓	✓	✓	✓	✓	✓
disposable	✓	✓	✓	✓	✓	✓
roleBased	✓	✓	✓	✓	✓	✓
catchAll	-	✓	✓	✓	✓	✓
typoSuggestion	-	✓	✓	✓	✓	✓
freeEmail	-	✓	✓	✓	✓	✓
spamTrap	-	-	-	✓	✓	✓
emailAuthentication	-	-	-	✓	✓	✓
blacklist	-	-	-	✓	✓	✓
domainTrust	-	-	-	✓	✓	✓
fraudDetection	-	-	-	✓	✓	✓
corporateEmail	-	-	✓	✓	✓	✓
mailboxProvider	-	-	✓	✓	✓	✓
smtpVerification	-	-	-	-	✓	✓

Score Impact

Check	Pass	Fail Impact
syntax	0	-100 (invalid)
domain	0	-80 to -90
mxRecords	0	-70 to -80
disposable	0	-30 to -50
spamTrap (critical)	0	-60
roleBased (high)	0	-40
typoSuggestion	0	-15 to -35
catchAll	0	-15
blacklist	0	-70
fraudDetection	0	-40 to -60
emailAuthentication	+10	-10
domainTrust	+10	-15
corporateEmail	+10	-5