curl --request POST \
  --url https://api.paubox.com/v1/email/schedule \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "data": {
    "message": {
      "recipients": [
        "recipient@host.com"
      ],
      "headers": {
        "subject": "Holiday greeting",
        "from": "sender@verifieddomain.com"
      },
      "content": {
        "text/plain": "Happy holidays!"
      }
    },
    "scheduled_at": "2025-12-25T15:00:00Z"
  }
}
'

import requests

url = "https://api.paubox.com/v1/email/schedule"

payload = { "data": {
        "message": {
            "recipients": ["recipient@host.com"],
            "headers": {
                "subject": "Holiday greeting",
                "from": "sender@verifieddomain.com"
            },
            "content": { "text/plain": "Happy holidays!" }
        },
        "scheduled_at": "2025-12-25T15:00:00Z"
    } }
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    data: {
      message: {
        recipients: ['recipient@host.com'],
        headers: {subject: 'Holiday greeting', from: 'sender@verifieddomain.com'},
        content: {'text/plain': 'Happy holidays!'}
      },
      scheduled_at: '2025-12-25T15:00:00Z'
    }
  })
};

fetch('https://api.paubox.com/v1/email/schedule', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.paubox.com/v1/email/schedule",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'data' => [
        'message' => [
                'recipients' => [
                                'recipient@host.com'
                ],
                'headers' => [
                                'subject' => 'Holiday greeting',
                                'from' => 'sender@verifieddomain.com'
                ],
                'content' => [
                                'text/plain' => 'Happy holidays!'
                ]
        ],
        'scheduled_at' => '2025-12-25T15:00:00Z'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.paubox.com/v1/email/schedule"

	payload := strings.NewReader("{\n  \"data\": {\n    \"message\": {\n      \"recipients\": [\n        \"recipient@host.com\"\n      ],\n      \"headers\": {\n        \"subject\": \"Holiday greeting\",\n        \"from\": \"sender@verifieddomain.com\"\n      },\n      \"content\": {\n        \"text/plain\": \"Happy holidays!\"\n      }\n    },\n    \"scheduled_at\": \"2025-12-25T15:00:00Z\"\n  }\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.paubox.com/v1/email/schedule")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"data\": {\n    \"message\": {\n      \"recipients\": [\n        \"recipient@host.com\"\n      ],\n      \"headers\": {\n        \"subject\": \"Holiday greeting\",\n        \"from\": \"sender@verifieddomain.com\"\n      },\n      \"content\": {\n        \"text/plain\": \"Happy holidays!\"\n      }\n    },\n    \"scheduled_at\": \"2025-12-25T15:00:00Z\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.paubox.com/v1/email/schedule")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"data\": {\n    \"message\": {\n      \"recipients\": [\n        \"recipient@host.com\"\n      ],\n      \"headers\": {\n        \"subject\": \"Holiday greeting\",\n        \"from\": \"sender@verifieddomain.com\"\n      },\n      \"content\": {\n        \"text/plain\": \"Happy holidays!\"\n      }\n    },\n    \"scheduled_at\": \"2025-12-25T15:00:00Z\"\n  }\n}"

response = http.request(request)
puts response.read_body

{
  "sourceTrackingId": "3d38ab13-0af8-4028-bd45-52e882e0d584",
  "scheduledAt": "2025-12-25T15:00:00Z",
  "state": "pending",
  "data": "Service OK"
}

{
  "errors": [
    {
      "code": 123,
      "title": "<string>",
      "details": "<string>"
    }
  ]
}