API Reference

REST API Reference

Base URL: https://api.mailsflux.net · All requests require an Authorization: Bearer mf_live_sk_… header.

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Authentication

All API requests must include your secret key in the Authorization header. Find your API key in your dashboard under Settings → API Keys. Never expose your secret key in client-side code.

Emails

POST/v1/emails/sendSend a transactional or marketing email

GET/v1/emails/:idRetrieve email status and delivery events

GET/v1/emailsList sent emails with filters and pagination

POST/v1/emails/batchSend up to 1,000 emails in a single request

Physical Mail

POST/v1/mail/sendSend an envelope, postcard, or parcel

GET/v1/mail/:idGet shipment status and tracking nodes

GET/v1/mailList physical mail sends

POST/v1/mail/validate-addressValidate and normalize a postal address

Templates

GET/v1/templatesList all email templates

POST/v1/templatesCreate a new email template

PUT/v1/templates/:idUpdate an existing template

DELETE/v1/templates/:idDelete a template

Audiences

GET/v1/audiencesList all audience segments

POST/v1/audiencesCreate a new audience segment

POST/v1/audiences/:id/contactsAdd contacts to an audience

DELETE/v1/audiences/:id/contacts/:emailRemove a contact from an audience

Suppressions

GET/v1/suppressionsList suppressed addresses (bounces, complaints, unsubscribes)

POST/v1/suppressionsManually add an address to the suppression list

DELETE/v1/suppressions/:emailRemove an address from the suppression list

Webhooks

GET/v1/webhooksList configured webhook endpoints

POST/v1/webhooksRegister a new webhook endpoint

DELETE/v1/webhooks/:idDelete a webhook endpoint

Domains

GET/v1/domainsList verified sending domains

POST/v1/domainsAdd a new sending domain

GET/v1/domains/:id/verifyTrigger DNS verification for a domain

GET/v1/domains/:id/reputationGet reputation score and metrics for a domain

Standard Response Format

// Success
{
  "id":         "msg_01JNPXR4KQ...",
  "status":     "queued",
  "queued_at":  "2026-04-11T09:32:17Z"
}

// Error
{
  "error": {
    "code":    "invalid_recipient",
    "message": "The 'to' field must be a valid email address.",
    "status":  422
  }
}

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