Один вызов HTTP отправляет сообщение.
Один вебхук подтверждает это.

import requests

r = requests.post(
    "https://api.smsmeteor.com/v1/messages/batch",
    headers={"Authorization": f"Bearer {KEY}",
             "Idempotency-Key": "batch-2026-09-21-01"},
    json={"messages": [
        {"to": "+14155550142", "from": "METEOR", "text": "Заказ №4821 отправлен."},
        {"to": "+447700900123", "from": "METEOR", "text": "Заказ №4822 отправлен."},
    ]},
)
for m in r.json()["messages"]:
    print(m["id"], m["status"], m["price"])

const r = await fetch("https://api.smsmeteor.com/v1/messages/batch", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.SMSMETEOR_KEY}`,
    "Idempotency-Key": "batch-2026-09-21-01",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({ messages: [
    { to: "+14155550142", from: "METEOR", text: "Заказ №4821 отправлен." },
    { to: "+447700900123", from: "METEOR", text: "Заказ №4822 отправлен." },
  ]}),
});
const { messages } = await r.json();

$ch = curl_init("https://api.smsmeteor.com/v1/messages/batch");
curl_setopt_array($ch, [
  CURLOPT_POST => true, CURLOPT_RETURNTRANSFER => true,
  CURLOPT_HTTPHEADER => ["Authorization: Bearer $key",
    "Idempotency-Key: batch-2026-09-21-01", "Content-Type: application/json"],
  CURLOPT_POSTFIELDS => json_encode(["messages" => [
    ["to" => "+14155550142", "from" => "METEOR", "text" => "Заказ №4821 отправлен."],
    ["to" => "+447700900123", "from" => "METEOR", "text" => "Заказ №4822 отправлен."],
  ]]),
]);
$res = json_decode(curl_exec($ch), true);

body, _ := json.Marshal(map[string]any{"messages": []map[string]string{
    {"to": "+14155550142", "from": "METEOR", "text": "Заказ №4821 отправлен."},
    {"to": "+447700900123", "from": "METEOR", "text": "Заказ №4822 отправлен."},
}})
req, _ := http.NewRequest("POST", "https://api.smsmeteor.com/v1/messages/batch", bytes.NewReader(body))
req.Header.Set("Authorization", "Bearer "+os.Getenv("SMSMETEOR_KEY"))
req.Header.Set("Idempotency-Key", "batch-2026-09-21-01")
req.Header.Set("Content-Type", "application/json")
res, err := http.DefaultClient.Do(req)

{ "batch_id": "bat_3Hq9Zr", "accepted": 2, "rejected": 0,
  "total_price": "0.0214", "currency": "USD",
  "messages": [ { "id": "msg_9Kd2fQ", "status": "queued", "price": "0.0084" },
                { "id": "msg_9Kd2fR", "status": "queued", "price": "0.0130" } ] }