curl --request POST \
  --url https://api.hubapi.com/automation/v4/actions/callbacks/{callbackId}/complete \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "outputFields": {},
  "typedOutputs": {},
  "failureReasonType": "<string>",
  "requestContext": {
    "source": "WORKFLOWS",
    "workflowId": 123,
    "actionId": 123
  }
}
'

import requests

url = "https://api.hubapi.com/automation/v4/actions/callbacks/{callbackId}/complete"

payload = {
    "outputFields": {},
    "typedOutputs": {},
    "failureReasonType": "<string>",
    "requestContext": {
        "source": "WORKFLOWS",
        "workflowId": 123,
        "actionId": 123
    }
}
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({
    outputFields: {},
    typedOutputs: {},
    failureReasonType: '<string>',
    requestContext: {source: 'WORKFLOWS', workflowId: 123, actionId: 123}
  })
};

fetch('https://api.hubapi.com/automation/v4/actions/callbacks/{callbackId}/complete', 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.hubapi.com/automation/v4/actions/callbacks/{callbackId}/complete",
  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([
    'outputFields' => [
        
    ],
    'typedOutputs' => [
        
    ],
    'failureReasonType' => '<string>',
    'requestContext' => [
        'source' => 'WORKFLOWS',
        'workflowId' => 123,
        'actionId' => 123
    ]
  ]),
  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.hubapi.com/automation/v4/actions/callbacks/{callbackId}/complete"

	payload := strings.NewReader("{\n  \"outputFields\": {},\n  \"typedOutputs\": {},\n  \"failureReasonType\": \"<string>\",\n  \"requestContext\": {\n    \"source\": \"WORKFLOWS\",\n    \"workflowId\": 123,\n    \"actionId\": 123\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.hubapi.com/automation/v4/actions/callbacks/{callbackId}/complete")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"outputFields\": {},\n  \"typedOutputs\": {},\n  \"failureReasonType\": \"<string>\",\n  \"requestContext\": {\n    \"source\": \"WORKFLOWS\",\n    \"workflowId\": 123,\n    \"actionId\": 123\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.hubapi.com/automation/v4/actions/callbacks/{callbackId}/complete")

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  \"outputFields\": {},\n  \"typedOutputs\": {},\n  \"failureReasonType\": \"<string>\",\n  \"requestContext\": {\n    \"source\": \"WORKFLOWS\",\n    \"workflowId\": 123,\n    \"actionId\": 123\n  }\n}"

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

This response has no body data.

{
  "message": "Invalid input (details will vary based on the error)",
  "correlationId": "aeb5f871-7f07-4993-9211-075dc63e7cbf",
  "category": "VALIDATION_ERROR",
  "links": {
    "knowledge-base": "https://www.hubspot.com/products/service/knowledge-base"
  }
}