Validation

Reject missing or malformed fields before a request is made.

Authorization

Treat invalid or revoked credentials as errors and stop retries until access is restored.

Temporary failures

Retry only when a future backend response explicitly allows it.

Parameters

Proposed code example

// Illustrative only — proposed interface
const response = await mailflow.messages.send({
  projectId: "prj_example",
  to: "recipient@example.com",
  templateId: "tpl_welcome"
});

Illustrative response

{
  "id": "msg_example",
  "status": "accepted",
  "environment": "test"
}

Error response example

{
  "error": {
    "code": "validation_error",
    "message": "A required field is missing."
  }
}