curl --request POST \
  --url https://api.sx.bet/user/multisig/add-signer/prepare \
  --header 'Content-Type: application/json' \
  --header 'x-sx-api-key: <api-key>' \
  --data '
{
  "safeAddress": "0x8E4c91A7D2b0f35e6A19c84d70B2e5F1a3c6D9e8",
  "newSigner": "0xbcc6D643e4159A75ED1dB4e13330230B82F2AEe5",
  "threshold": 2
}
'

import requests

url = "https://api.sx.bet/user/multisig/add-signer/prepare"

payload = {
    "safeAddress": "0x8E4c91A7D2b0f35e6A19c84d70B2e5F1a3c6D9e8",
    "newSigner": "0xbcc6D643e4159A75ED1dB4e13330230B82F2AEe5",
    "threshold": 2
}
headers = {
    "x-sx-api-key": "<api-key>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {'x-sx-api-key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    safeAddress: '0x8E4c91A7D2b0f35e6A19c84d70B2e5F1a3c6D9e8',
    newSigner: '0xbcc6D643e4159A75ED1dB4e13330230B82F2AEe5',
    threshold: 2
  })
};

fetch('https://api.sx.bet/user/multisig/add-signer/prepare', 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.sx.bet/user/multisig/add-signer/prepare",
  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([
    'safeAddress' => '0x8E4c91A7D2b0f35e6A19c84d70B2e5F1a3c6D9e8',
    'newSigner' => '0xbcc6D643e4159A75ED1dB4e13330230B82F2AEe5',
    'threshold' => 2
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "x-sx-api-key: <api-key>"
  ],
]);

$response = curl_exec($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.sx.bet/user/multisig/add-signer/prepare"

	payload := strings.NewReader("{\n  \"safeAddress\": \"0x8E4c91A7D2b0f35e6A19c84d70B2e5F1a3c6D9e8\",\n  \"newSigner\": \"0xbcc6D643e4159A75ED1dB4e13330230B82F2AEe5\",\n  \"threshold\": 2\n}")

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

	req.Header.Add("x-sx-api-key", "<api-key>")
	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.sx.bet/user/multisig/add-signer/prepare")
  .header("x-sx-api-key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"safeAddress\": \"0x8E4c91A7D2b0f35e6A19c84d70B2e5F1a3c6D9e8\",\n  \"newSigner\": \"0xbcc6D643e4159A75ED1dB4e13330230B82F2AEe5\",\n  \"threshold\": 2\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.sx.bet/user/multisig/add-signer/prepare")

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

request = Net::HTTP::Post.new(url)
request["x-sx-api-key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"safeAddress\": \"0x8E4c91A7D2b0f35e6A19c84d70B2e5F1a3c6D9e8\",\n  \"newSigner\": \"0xbcc6D643e4159A75ED1dB4e13330230B82F2AEe5\",\n  \"threshold\": 2\n}"

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

{
  "status": "success",
  "data": {
    "safeAddress": "0x8E4c91A7D2b0f35e6A19c84d70B2e5F1a3c6D9e8",
    "safeTxHash": "0x9c8f5b21e4d0a7c3f18b6e94d2a05c7318fa4b62d9e0173c5a8b2f4e6019d3c7",
    "typedData": {
      "primaryType": "SafeTx",
      "domain": {
        "chainId": 4162,
        "verifyingContract": "0x8E4c91A7D2b0f35e6A19c84d70B2e5F1a3c6D9e8"
      },
      "message": {
        "to": "0x4361123dbdc1D812fdf7D27045aF358C9C8AA70A",
        "value": "0",
        "operation": 0,
        "nonce": 3
      }
    },
    "safeTransactionData": {
      "to": "0x4361123dbdc1D812fdf7D27045aF358C9C8AA70A",
      "value": "0",
      "data": "0x",
      "operation": 0,
      "nonce": 3
    }
  }
}

{
  "message": "invalid safeAddress",
  "error": "Bad Request",
  "statusCode": 400
}

{
  "message": "BAD_AUTH",
  "error": "Unauthorized",
  "statusCode": 401
}

{
  "message": "the target Safe is not associated with your account",
  "error": "Forbidden",
  "statusCode": 403
}

{
  "message": "your proxy wallet is not deployed yet",
  "error": "Conflict",
  "statusCode": 409
}