API Docs

const response = await fetch("https://www.instamessage.in/api/v1/messages/send", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_ACCESS_TOKEN",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    instance_id: "YOUR_INSTANCE_ID",
    to: "919876543210",
    message: "Hello from InstaMessage!",
  }),
});

const data = await response.json();
console.log(data);

$curl = curl_init();

curl_setopt_array($curl, [
    CURLOPT_URL => 'https://www.instamessage.in/api/v1/messages/send',
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_TIMEOUT => 30,
    CURLOPT_POST => true,
    CURLOPT_POSTFIELDS => json_encode([
        'instance_id' => 'YOUR_INSTANCE_ID',
        'to' => '919876543210',
        'message' => 'Hello from InstaMessage!',
    ]),
    CURLOPT_HTTPHEADER => [
        'Content-Type: application/json',
        'Accept: application/json',
        'Authorization: Bearer YOUR_ACCESS_TOKEN',
    ],
]);

$response = curl_exec($curl);

if ($response === false) {
    // Couldn't reach the API at all (DNS, timeout, SSL, ...).
    echo 'Connection error: ' . curl_error($curl);
} else {
    $status = curl_getinfo($curl, CURLINFO_HTTP_CODE);
    $data = json_decode($response, true);

    if ($status === 200 && ! empty($data['success'])) {
        echo 'Sent! Message ID: ' . $data['message_id'];
    } else {
        echo "Failed (HTTP $status): " . ($data['error'] ?? $response);
    }
}

Uses PHP's built-in curl extension (enabled on almost every host) — no Composer package needed.

import requests

response = requests.post(
    "https://www.instamessage.in/api/v1/messages/send",
    headers={"Authorization": "Bearer YOUR_ACCESS_TOKEN"},
    json={
        "instance_id": "YOUR_INSTANCE_ID",
        "to": "919876543210",
        "message": "Hello from InstaMessage!",
    },
)

data = response.json()
print(data)

Needs the requests package (pip install requests).

using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;

using var client = new HttpClient();
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", "YOUR_ACCESS_TOKEN");

var payload = new
{
    instance_id = "YOUR_INSTANCE_ID",
    to = "919876543210",
    message = "Hello from InstaMessage!"
};

var content = new StringContent(JsonSerializer.Serialize(payload), Encoding.UTF8, "application/json");
var response = await client.PostAsync("https://www.instamessage.in/api/v1/messages/send", content);
var data = await response.Content.ReadAsStringAsync();

Console.WriteLine(data);

Uses only the .NET base class library (System.Text.Json) — no extra NuGet package needed.

HttpClient client = HttpClient.newHttpClient();

String body = "{"
    + "\"instance_id\":\"YOUR_INSTANCE_ID\","
    + "\"to\":\"919876543210\","
    + "\"message\":\"Hello from InstaMessage!\""
    + "}";

HttpRequest request = HttpRequest.newBuilder()
    .uri(URI.create("https://www.instamessage.in/api/v1/messages/send"))
    .header("Authorization", "Bearer YOUR_ACCESS_TOKEN")
    .header("Content-Type", "application/json")
    .POST(HttpRequest.BodyPublishers.ofString(body))
    .build();

HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
System.out.println(response.body());

Uses java.net.http.HttpClient, built into the JDK since Java 11 — no extra dependency.