Create a broadcast
Creates a broadcast. Omit scheduled_at to save a draft, pass a future timestamp to schedule it, or pass send_now: true to resolve the audience and start sending immediately.
Sending a 1:1 email? Use POST /v1/email/inboxes/{inbox_id}/messages instead — it creates a tracked thread you can reply within.
Authorizations
API key in the format: Bearer {api_token}
Headers
Makes this write safe to retry: a repeat with the same key replays the first response instead of creating a second resource. Scoped to the account, remembered for 24 hours; reusing a key with a different payload is an error.
255Body
Sender email address (uses account default if omitted)
List of recipient email addresses
Email subject line. Takes the same variables as body.
Inbox preview line. Takes the same variables as body.
255Email body (HTML or plain text). Variables, filled per recipient from their customer record when each batch is sent: {{customer.first_name}}, {{customer.last_name}}, {{customer.email}}, {{business.name}}, {{customer.fields.}}. customer.fields.<key> reads <key> from the customer's metadata. An address in to that belongs to no customer is sent without customer data, so its variables render blank or as their defaults. Put {{unsubscribe_url}} in an href to place the recipient's opt-out link. Any other {{ }} is rejected with 422.
Filter recipients by customer type
Send to all customers
Response
The created broadcast
draft, scheduled, sending, sent, canceled, failed 
