Custom Rules

Custom rules let you override classification results for specific domains or MX patterns. When a rule matches, it takes priority over the default classification logic.

This is useful when:

  • Your organization uses a provider that EmailKind doesn't recognize
  • You want to reclassify specific domains differently (e.g., mark a domain as "business" instead of "personal")
  • You have internal mail servers with custom MX records

Rule types

| Type | Description | Example | |---|---|---| | domain | Exact domain match | internal.company.com | | mx_pattern | Wildcard MX pattern match | *.mail.myhost.com |

Domain rules match the exact domain being classified. They have the highest priority.

MX pattern rules match against the MX records of the classified domain. Wildcards (*) are supported:

  • *.example.com matches any subdomain of example.com
  • mx*.example.com matches mx1.example.com, mx2.example.com, etc.

API endpoints

List rules

GET /v1/rules

curl -H "Authorization: Bearer sk_live_YOUR_KEY" \
  "https://emailkind.com/v1/rules"

Response:

{
  "success": true,
  "request_id": "req_abc123",
  "rules": [
    {
      "id": "550e8400-e29b-41d4-a716-446655440000",
      "match_type": "domain",
      "match_value": "internal.company.com",
      "provider_name": "Internal Mail",
      "provider_type": "business",
      "created_at": "2025-01-15T10:30:00Z"
    }
  ],
  "count": 1
}

Create a rule

POST /v1/rules

curl -X POST -H "Authorization: Bearer sk_live_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "match_type": "domain",
    "match_value": "internal.company.com",
    "provider_name": "Internal Mail",
    "provider_type": "business"
  }' \
  "https://emailkind.com/v1/rules"

Parameters:

| Field | Type | Required | Description | |---|---|---|---| | match_type | string | Yes | domain or mx_pattern | | match_value | string | Yes | The domain or MX pattern to match | | provider_name | string | Yes | Display name for the provider | | provider_type | string | Yes | One of: business, personal, disposable, education, hosting, self_hosted |

Response:

{
  "success": true,
  "request_id": "req_def456",
  "rule": {
    "id": "550e8400-e29b-41d4-a716-446655440000",
    "match_type": "domain",
    "match_value": "internal.company.com",
    "provider_name": "Internal Mail",
    "provider_type": "business",
    "created_at": "2025-01-15T10:30:00Z"
  }
}

Delete a rule

DELETE /v1/rules/{id}

curl -X DELETE -H "Authorization: Bearer sk_live_YOUR_KEY" \
  "https://emailkind.com/v1/rules/550e8400-e29b-41d4-a716-446655440000"

Limits

  • Maximum 50 rules per account
  • Available on Starter plan and above
  • Rules are applied in real-time — no delay after creation
  • If a domain matches both a domain rule and an MX pattern rule, the domain rule takes priority

How rules affect classification

When a custom rule matches, the API response will include:

  • provider.id: custom_ followed by the provider name (lowercase, underscored)
  • provider.name: Your custom provider name
  • provider.type: Your specified provider type
  • confidence: 1.0 (since the match is user-defined)
  • Classification flags (is_business, is_free, etc.) are set based on the provider type