Developer API

Integrate cryptographic email verification and identity-bound communication into your software systems.

Getting Started

The MXend API is structured around REST. All API requests must be made over HTTPS. The API expects all request bodies to be formatted as JSON, and returns JSON-encoded responses with standard HTTP response codes.

To begin integrating with the MXend secure mail system, you must register your application in the administrative console to obtain your client credentials.

Authentication

Authenticate your API requests by including a bearer token in the HTTP Authorization header. Your API tokens carry significant privileges, so please keep them secure.

Request Header 
Authorization: Bearer mx_live_smp_tokens_prod

Sending Messages

Send secure, identity-verified email messages programmatically. Outgoing API messages are signed automatically using your organization's verified sender credentials.

POST /v1/messages 
{
  "sender": "verify@yourdomain.com",
  "recipient": "partner@partnerdomain.com",
  "subject": "Secure Project Update",
  "body": "This communication is secured and signed by MXend."
}

Verifying Identities

Query the MXend platform to verify the cryptographic identity validation status of any registered user or domain.

GET /v1/identities/verify 
{
  "identity": "user@domain.com",
  "verified": true,
  "verification_level": "advanced",
  "last_updated": "2026-06-12T12:00:00Z"
}

Error Handling

MXend uses standard HTTP response codes to indicate the success or failure of an API request. Codes in the 2xx range indicate success, 4xx indicate request errors, and 5xx indicate system issues.