Per-domain and per-IP reputation tracked separately

Domain reputation and IP reputation are independent signals that mailbox providers track and report separately — Google Postmaster Tools explicitly distinguishes them. A domain reputation hit means your content or authentication history is the problem; an IP reputation hit means the specific IP's sending behavior is the problem. If you only track a combined metric, you cannot determine whether to reconfigure content and authentication (domain issue) or rotate to a new IP (IP issue). Without separation, diagnosing and recovering from deliverability problems is guesswork that delays resolution and extends inbox-blocking.

Store domain and IP reputation as separate Prisma models, each with its own updatedAt and queryable by its identifier. Use this schema or equivalent in prisma/schema.prisma:

model DomainReputation {
  id           String   @id @default(uuid())
  domain       String   @unique
  spamRate     Float?
  inboxRate    Float?
  dkimPassRate Float?
  spfPassRate  Float?
  dmarcPassRate Float?
  updatedAt    DateTime @updatedAt
}

model IpReputation {
  id              String   @id @default(uuid())
  ipAddress       String   @unique
  spamRate        Float?
  microsoftCategory String? // Green / Yellow / Red
  lastChecked     DateTime
  updatedAt       DateTime @updatedAt
}

Populate DomainReputation from Google Postmaster Tools and IpReputation from Microsoft SNDS on a daily cron. Alerting logic should query each table independently so a domain reputation alert does not suppress an IP reputation alert.