AddContact#

import requests

url = "{{apiUrl}}/waInstance{{idInstance}}/addContact/{{apiTokenInstance}}"

payload = {
    "chatId": "79876543210@c.us",
    "firstName": "Иван",
    "lastName": "Царевич",
    "saveInAddressbook": true
}
headers = {
'Content-Type': 'application/json'
}

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

print(response.text.encode('utf8'))

<?php
//The apiUrl, idInstance and apiTokenInstance values are available in console, double brackets must be removed
$url = '{{apiUrl}}/waInstance{{idInstance}}/addContact/{{apiTokenInstance}}';

//chatId is the number (@c.us)  
$data = array(
    'chatId' => '71234567890@c.us',
    'firstName' => 'Иван',
    'lastName' => 'Царевич',
    'saveInAddressbook' => 'true',
);

$options = array(
    'http' => array(
        'header' => "Content-Type: application/json\r\n",
        'method' => 'POST',
        'content' => json_encode($data)
    )
);

$context = stream_context_create($options);

$response = file_get_contents($url, false, $context);

echo $response;
?>

curl --location '{{apiUrl}}/waInstance{{idInstance}}/addContact/{{apiTokenInstance}}' \
--header 'Content-Type: application/json' \
--data-raw '{
    "chatId": "71234567890@c.us",
    "firstName": "Иван",
    "lastName": "Царевич",
    "saveInAddressbook": true
}'

Sub AddContact()
Dim URL As String
Dim RequestBody As String
Dim http As Object

' The apiUrl, idInstance and apiTokenInstance values are available in console, double brackets must be removed
URL = "{{apiUrl}}/waInstance{{idInstance}}/addContact/{{apiTokenInstance}}"

' chatId is the number (@c.us)
RequestBody = "{""chatId"":""71234567890@c.us"",""firstName"":""Иван"", ""lastName"":""Царевич"", ""saveInAddressbook"":""true""}"

Set http = CreateObject("MSXML2.XMLHTTP")

With http
    .Open "POST", URL, False
    .setRequestHeader "Content-Type", "application/json"
    .send RequestBody
End With

Set http = Nothing

End Sub

program addContact;

{$APPTYPE CONSOLE}

uses
System.SysUtils,
System.Classes, System.Net.HttpClient, System.Net.URLClient, System.Net.HttpClientComponent;

var
HttpClient: TNetHTTPClient;
RequestBody: TStringStream;
RequestHeaders: TNetHeaders;
Response: IHTTPResponse;
EndpointURL, ID_INSTANCE, API_TOKEN_INSTANCE: string;

begin
ID_INSTANCE := '110100001';
API_TOKEN_INSTANCE := 'd75b3a66374942c5b3c019c698abc2067e151558acbd451234';

EndpointURL := 'https://api.green-api.com/waInstance' + ID_INSTANCE + '/addContact/' + API_TOKEN_INSTANCE;

HttpClient := TNetHTTPClient.Create(nil);
RequestBody := TStringStream.Create('{ "chatId": "79876543210@c.us", "firstName": "Иван", "lastName": "Царевич", "saveInAddressbook": true }', TEncoding.UTF8);
RequestHeaders := [
    TNetHeader.Create('Content-Type', 'application/json')
];

try
    Response := HTTPClient.Post(EndpointURL, RequestBody, nil, RequestHeaders);

    if Response.StatusCode = 200 then
    Writeln('[Response]: ' + Response.ContentAsString)
    else
    Writeln('[ERROR ' + IntToStr(Response.StatusCode) + ']:' + Response.StatusText + '' + Response.ContentAsString);

    readln;
except
    on E: Exception do
    Writeln(E.ClassName, ': ', E.Message);
end;

HttpClient.Free;
RequestBody.Free;

end.