curl --request POST \
  --url https://api.cal.com/v2/bookings/{bookingUid}/decline \
  --header 'Authorization: <authorization>' \
  --header 'Content-Type: application/json' \
  --header 'cal-api-version: <cal-api-version>' \
  --data '
{
  "reason": "Host has to take another call"
}
'

import requests

url = "https://api.cal.com/v2/bookings/{bookingUid}/decline"

payload = { "reason": "Host has to take another call" }
headers = {
    "cal-api-version": "<cal-api-version>",
    "Authorization": "<authorization>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'cal-api-version': '<cal-api-version>',
    Authorization: '<authorization>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({reason: 'Host has to take another call'})
};

fetch('https://api.cal.com/v2/bookings/{bookingUid}/decline', 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.cal.com/v2/bookings/{bookingUid}/decline",
  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([
    'reason' => 'Host has to take another call'
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: <authorization>",
    "Content-Type: application/json",
    "cal-api-version: <cal-api-version>"
  ],
]);

$response = curl_exec($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.cal.com/v2/bookings/{bookingUid}/decline"

	payload := strings.NewReader("{\n  \"reason\": \"Host has to take another call\"\n}")

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

	req.Header.Add("cal-api-version", "<cal-api-version>")
	req.Header.Add("Authorization", "<authorization>")
	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.cal.com/v2/bookings/{bookingUid}/decline")
  .header("cal-api-version", "<cal-api-version>")
  .header("Authorization", "<authorization>")
  .header("Content-Type", "application/json")
  .body("{\n  \"reason\": \"Host has to take another call\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.cal.com/v2/bookings/{bookingUid}/decline")

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

request = Net::HTTP::Post.new(url)
request["cal-api-version"] = '<cal-api-version>'
request["Authorization"] = '<authorization>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"reason\": \"Host has to take another call\"\n}"

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

{
  "status": "success",
  "data": {
    "id": 123,
    "uid": "booking_uid_123",
    "title": "Consultation",
    "description": "Learn how to integrate scheduling into marketplace.",
    "hosts": [
      {
        "id": 1,
        "name": "Jane Doe",
        "email": "jane100@example.com",
        "displayEmail": "jane100@example.com",
        "username": "jane100",
        "timeZone": "America/Los_Angeles"
      }
    ],
    "status": "accepted",
    "start": "2024-08-13T15:30:00Z",
    "end": "2024-08-13T16:30:00Z",
    "duration": 60,
    "eventTypeId": 50,
    "eventType": {
      "id": 1,
      "slug": "some-event"
    },
    "location": "https://example.com/meeting",
    "absentHost": true,
    "createdAt": "2024-08-13T15:30:00Z",
    "updatedAt": "2024-08-13T15:30:00Z",
    "attendees": [
      {
        "name": "John Doe",
        "email": "john@example.com",
        "displayEmail": "john@example.com",
        "timeZone": "America/New_York",
        "absent": false,
        "language": "en",
        "phoneNumber": "+1234567890"
      }
    ],
    "bookingFieldsResponses": {
      "customField": "customValue"
    },
    "cancellationReason": "User requested cancellation",
    "cancelledByEmail": "canceller@example.com",
    "reschedulingReason": "User rescheduled the event",
    "rescheduledByEmail": "rescheduler@example.com",
    "rescheduledFromUid": "previous_uid_123",
    "rescheduledToUid": "new_uid_456",
    "meetingUrl": "https://example.com/recurring-meeting",
    "metadata": {
      "key": "value"
    },
    "rating": 4,
    "icsUid": "ics_uid_123",
    "guests": [
      "guest1@example.com",
      "guest2@example.com"
    ]
  }
}