이메일 검증 API

{
  "email": "user@company.com",
  "normalized_email": "user@company.com",
  "result": "valid",
  "result_detail": "mx_verified",
  "risk": "low",
  "confidence": 0.62,
  "decision": "accept",
  "reasons": ["mx_found", "not_disposable", "mailbox_not_checked", "redundant_mx_records"],
  "verification": {
    "syntax_valid": true,
    "mx_found": true,
    "mx_records": ["mx1.company.com", "mx2.company.com"],
    "smtp_verified": null,
    "mailbox_exists": null,
    "catch_all": null
  },
  "classification": {
    "disposable": false,
    "role_based": false,
    "free_provider": false,
    "provider": null
  },
  "reputation": {
    "dnsbl_listed": false,
    "threat_level": null
  },
  "quality": {
    "score": 100,
    "grade": "A",
    "flags": []
  },
  "signals": {
    "domain_profile": { "status": "pass", "reason": "clean_domain_profile" },
    "local_part": { "status": "pass", "reason": "clean_local_part" },
    "mx_redundancy": { "status": "pass", "reason": "redundant_mx_records" },
    "domain_authentication": { "status": "pass", "reason": "domain_authentication_strong" },
    "toxicity": { "status": "pass", "reason": "not_toxic" }
  },
  "recommendation": {
    "signup": "allow",
    "marketing": "send",
    "cold_outreach": "send"
  },
  "deliverability": {
    "status": "deliverable",
    "sub_status": "mx_verified",
    "safe_to_send": true,
    "is_toxic": false,
    "is_gibberish": false
  },
  "tier": "basic",
  "credits_used": 1
}