curl --request POST \
  --url https://api.monaco.com/v1/contacts/{contact_id}/merge/preview \
  --header 'Content-Type: application/json' \
  --data '
{
  "source_contact_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
}
'

import requests

url = "https://api.monaco.com/v1/contacts/{contact_id}/merge/preview"

payload = { "source_contact_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a" }
headers = {"Content-Type": "application/json"}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({source_contact_id: '3c90c3cc-0d44-4b50-8888-8dd25736052a'})
};

fetch('https://api.monaco.com/v1/contacts/{contact_id}/merge/preview', 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.monaco.com/v1/contacts/{contact_id}/merge/preview",
  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([
    'source_contact_id' => '3c90c3cc-0d44-4b50-8888-8dd25736052a'
  ]),
  CURLOPT_HTTPHEADER => [
    "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.monaco.com/v1/contacts/{contact_id}/merge/preview"

	payload := strings.NewReader("{\n  \"source_contact_id\": \"3c90c3cc-0d44-4b50-8888-8dd25736052a\"\n}")

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

	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.monaco.com/v1/contacts/{contact_id}/merge/preview")
  .header("Content-Type", "application/json")
  .body("{\n  \"source_contact_id\": \"3c90c3cc-0d44-4b50-8888-8dd25736052a\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.monaco.com/v1/contacts/{contact_id}/merge/preview")

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

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"source_contact_id\": \"3c90c3cc-0d44-4b50-8888-8dd25736052a\"\n}"

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

{
  "data": {
    "target_contact": {
      "id": "<string>",
      "name": "<string>",
      "email": "<string>",
      "linkedin_url": "<string>",
      "title": "<string>",
      "archived": false
    },
    "source_contact": {
      "id": "<string>",
      "name": "<string>",
      "email": "<string>",
      "linkedin_url": "<string>",
      "title": "<string>",
      "archived": false
    },
    "merged_contact": {
      "id": "<string>",
      "name": "<string>",
      "email": "<string>",
      "linkedin_url": "<string>",
      "title": "<string>",
      "archived": false
    },
    "fields_filled_from_source": [
      "<string>"
    ],
    "notes_appended": true,
    "counts": {
      "plays_moved": 123,
      "user_tasks_moved": 123,
      "tags_added": 123,
      "audience_memberships_moved": 123,
      "opportunity_links_moved": 123,
      "custom_fields_filled": 123
    },
    "blocking_sequences": [
      {
        "sequence_id": "<string>",
        "status": "<string>",
        "contact": {
          "id": "<string>",
          "name": "<string>",
          "email": "<string>"
        },
        "name": "<string>",
        "campaign_name": "<string>"
      }
    ],
    "requires_sequence_stop": true
  },
  "meta": {
    "timestamp": "2023-11-07T05:31:56Z"
  }
}

{
  "error": {
    "code": "not_found",
    "message": "Resource not found",
    "blocking_sequence_count": 123
  }
}

{
  "error": {
    "code": "not_found",
    "message": "Resource not found"
  }
}