curl --request POST \
  --url https://api.mailbeast.ai/v1/emails/{id}/reply \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "body": {
    "html": "<p>Thanks, that works for me.</p>",
    "text": "Thanks, that works for me."
  },
  "cc": [
    "[email protected]"
  ],
  "bcc": [
    "[email protected]"
  ]
}
'

import requests

url = "https://api.mailbeast.ai/v1/emails/{id}/reply"

payload = {
    "body": {
        "html": "<p>Thanks, that works for me.</p>",
        "text": "Thanks, that works for me."
    },
    "cc": ["[email protected]"],
    "bcc": ["[email protected]"]
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    body: JSON.stringify({html: '<p>Thanks, that works for me.</p>', text: 'Thanks, that works for me.'}),
    cc: ['[email protected]'],
    bcc: ['[email protected]']
  })
};

fetch('https://api.mailbeast.ai/v1/emails/{id}/reply', 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.mailbeast.ai/v1/emails/{id}/reply",
  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([
    'body' => [
        'html' => '<p>Thanks, that works for me.</p>',
        'text' => 'Thanks, that works for me.'
    ],
    'cc' => [
        '[email protected]'
    ],
    'bcc' => [
        '[email protected]'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "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.mailbeast.ai/v1/emails/{id}/reply"

	payload := strings.NewReader("{\n  \"body\": {\n    \"html\": \"<p>Thanks, that works for me.</p>\",\n    \"text\": \"Thanks, that works for me.\"\n  },\n  \"cc\": [\n    \"[email protected]\"\n  ],\n  \"bcc\": [\n    \"[email protected]\"\n  ]\n}")

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

	req.Header.Add("Authorization", "Bearer <token>")
	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.mailbeast.ai/v1/emails/{id}/reply")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"body\": {\n    \"html\": \"<p>Thanks, that works for me.</p>\",\n    \"text\": \"Thanks, that works for me.\"\n  },\n  \"cc\": [\n    \"[email protected]\"\n  ],\n  \"bcc\": [\n    \"[email protected]\"\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.mailbeast.ai/v1/emails/{id}/reply")

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

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"body\": {\n    \"html\": \"<p>Thanks, that works for me.</p>\",\n    \"text\": \"Thanks, that works for me.\"\n  },\n  \"cc\": [\n    \"[email protected]\"\n  ],\n  \"bcc\": [\n    \"[email protected]\"\n  ]\n}"

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

{
  "id": "5e9a3c81-7d24-4b60-9f13-8a6c2e0d4b57",
  "threadId": "13a265fd-f0f2-b1d1-d6fc-154e483183e7",
  "status": "queued"
}

{
  "error": {
    "type": "invalid_request_error",
    "code": "validation_failed",
    "message": "One or more fields are invalid.",
    "status": 400,
    "requestId": "e4f1c0b2-6a3d-4b8e-9f21-0a1b2c3d4e5f",
    "details": [
      "name should not be empty"
    ]
  }
}

{
  "error": {
    "type": "authentication_error",
    "code": "unauthenticated",
    "message": "Missing or invalid API key.",
    "status": 401,
    "requestId": "e4f1c0b2-6a3d-4b8e-9f21-0a1b2c3d4e5f"
  }
}

{
  "error": {
    "type": "invalid_request_error",
    "code": "plan_limit_exceeded",
    "message": "A plan limit was reached.",
    "status": 402,
    "requestId": "e4f1c0b2-6a3d-4b8e-9f21-0a1b2c3d4e5f"
  }
}

{
  "error": {
    "type": "authorization_error",
    "code": "permission_denied",
    "message": "This API key is missing the required scope.",
    "status": 403,
    "requestId": "e4f1c0b2-6a3d-4b8e-9f21-0a1b2c3d4e5f"
  }
}

{
  "error": {
    "type": "invalid_request_error",
    "code": "not_found",
    "message": "Resource not found.",
    "status": 404,
    "requestId": "e4f1c0b2-6a3d-4b8e-9f21-0a1b2c3d4e5f"
  }
}

{
  "error": {
    "type": "invalid_request_error",
    "code": "conflict",
    "message": "The request conflicts with an existing resource.",
    "status": 409,
    "requestId": "e4f1c0b2-6a3d-4b8e-9f21-0a1b2c3d4e5f"
  }
}

{
  "error": {
    "type": "invalid_request_error",
    "code": "idempotency_key_reused",
    "message": "The Idempotency-Key was already used with a different request body. Use a new key for a new operation.",
    "status": 422,
    "requestId": "e4f1c0b2-6a3d-4b8e-9f21-0a1b2c3d4e5f"
  }
}

{
  "error": {
    "type": "rate_limit_error",
    "code": "rate_limited",
    "message": "Too many requests. Retry after the interval in the Retry-After header.",
    "status": 429,
    "requestId": "e4f1c0b2-6a3d-4b8e-9f21-0a1b2c3d4e5f",
    "retryAfter": 30
  }
}