Sends transactional emails to specified recipients with support for personalization, attachments, and tracking.
The API validates the request synchronously and returns 202 Accepted when the email is queued. Actual sending and personalization happen asynchronously in a worker. A 202 does not guarantee delivery; it means the request was accepted and queued. Per-recipient success/failure is not returned in the API response.
Optional headers: List-Unsubscribe (passed through for list-unsubscribe), X-SendPost-Mock-Email: true (mock send, if supported).
Team API key for authentication. Find your API key in SendX Settings → Team API Key.
Example:
X-Team-ApiKey: your_team_api_key_here1"Your Subject Here"
"<h1>Your HTML Content</h1>"
"Your Text Content"
Custom headers can be added to the email. These will be passed on when receving webhooks events for this email.
{ "X-Custom-Header": "Value" }