Email Service

Cora uses two distinct email channels:

Channel	Provider	Purpose
Campaign emails	Gmail API (OAuth)	Outbound sales sequences — sent via connected sender accounts
Transactional emails	Resend	Auth emails (verification, password reset, 2FA)

Campaign Emails — Gmail OAuth

Campaign emails are sent through Gmail accounts connected by the brand. This provides:

• High deliverability (uses the sender's real Gmail account)
• Thread continuity (replies land in the same Gmail thread)
• Warmup management (gradual daily send limit increases)

Sender Account Flow

Warmup

New Gmail accounts start with a low daily send limit. The worker cron resets sendsToday = 0 each midnight UTC and progressively increases dailyLimit based on warmup schedules. Accounts in warmup are skipped if they've reached their current limit; the worker tries up to 3 accounts before rescheduling.

Reply Detection

Inbound Gmail replies are detected via webhook callbacks. When a reply is received:

1. CampaignLeads.hasReplied is set to true
2. All pending step jobs for that contact are skipped
3. A Conversation record captures the thread for the inbox view

Transactional Emails — Resend

Auth-related emails are sent via Resend using the RESEND_API_KEY env var. Templates are defined in packages/auth/src/emails.ts:

• Email address verification on sign-up
• Magic link / password reset
• Two-factor auth codes

Sender Account Data Model

The SenderAccount model (stored in MongoDB) tracks per-account state:

Field	Purpose
connectionStatus	VERIFIED / BROKEN / PENDING
isActive	Whether the account can be used for sending
dailyLimit	Current max sends per day (increases with warmup)
sendsToday	Counter reset each midnight
lastSendAt	Timestamp of last outbound message
accessToken / refreshToken	Gmail OAuth credentials