curl --request GET \
  --url 'https://api.hubapi.com/automation/v4/actions/{appId}/{definitionId}?hapikey='

import requests

url = "https://api.hubapi.com/automation/v4/actions/{appId}/{definitionId}?hapikey="

response = requests.get(url)

print(response.text)

const options = {method: 'GET'};

fetch('https://api.hubapi.com/automation/v4/actions/{appId}/{definitionId}?hapikey=', 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/{appId}/{definitionId}?hapikey=",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://api.hubapi.com/automation/v4/actions/{appId}/{definitionId}?hapikey="

	req, _ := http.NewRequest("GET", url, nil)

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.get("https://api.hubapi.com/automation/v4/actions/{appId}/{definitionId}?hapikey=")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.hubapi.com/automation/v4/actions/{appId}/{definitionId}?hapikey=")

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

request = Net::HTTP::Get.new(url)

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

{
  "actionUrl": "<string>",
  "functions": [
    {
      "functionType": "POST_ACTION_EXECUTION",
      "id": "<string>"
    }
  ],
  "id": "<string>",
  "inputFields": [
    {
      "isRequired": true,
      "typeDefinition": {
        "name": "<string>",
        "options": [
          {
            "label": "<string>",
            "value": "<string>",
            "description": "<string>",
            "displayOrder": 123
          }
        ],
        "type": "bool",
        "description": "<string>",
        "fieldType": "booleancheckbox",
        "helpText": "<string>",
        "label": "<string>",
        "optionsUrl": "<string>",
        "referencedObjectType": "OWNER"
      },
      "supportedValueTypes": [
        "STATIC_VALUE"
      ]
    }
  ],
  "labels": {},
  "objectTypes": [
    "<string>"
  ],
  "published": true,
  "revisionId": "<string>",
  "archivedAt": 123,
  "executionRules": [
    {
      "conditions": {},
      "labelName": "<string>"
    }
  ],
  "inputFieldDependencies": [
    {
      "controllingFieldName": "<string>",
      "dependencyType": "SINGLE_FIELD",
      "dependentFieldNames": [
        "<string>"
      ]
    }
  ],
  "objectRequestOptions": {
    "properties": [
      "<string>"
    ]
  },
  "outputFields": [
    {
      "typeDefinition": {
        "externalOptions": true,
        "name": "<string>",
        "options": [
          {
            "description": "<string>",
            "displayOrder": 123,
            "doubleData": 123,
            "hidden": true,
            "label": "<string>",
            "readOnly": true,
            "value": "<string>"
          }
        ],
        "schema": {
          "type": "INTEGER",
          "maximum": 123,
          "minimum": 123
        },
        "type": "bool",
        "useChirp": true,
        "description": "<string>",
        "externalOptionsReferenceType": "<string>",
        "fieldType": "booleancheckbox",
        "helpText": "<string>",
        "label": "<string>",
        "optionsUrl": "<string>",
        "referencedObjectType": "ABANDONED_CART"
      }
    }
  ]
}

{
  "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"
  }
}