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POST
/
v3
/
video-agents
/
{session_id}
Send Message or Request Revision
curl --request POST \
  --url https://api.heygen.com/v3/video-agents/{session_id} \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "message": "<string>",
  "avatar_id": "<string>",
  "voice_id": "<string>",
  "brand_kit_id": "<string>",
  "files": [
    {
      "type": "<string>",
      "url": "<string>"
    }
  ]
}
'
import requests

url = "https://api.heygen.com/v3/video-agents/{session_id}"

payload = {
    "message": "<string>",
    "avatar_id": "<string>",
    "voice_id": "<string>",
    "brand_kit_id": "<string>",
    "files": [
        {
            "type": "<string>",
            "url": "<string>"
        }
    ]
}
headers = {
    "x-api-key": "<api-key>",
    "Content-Type": "application/json"
}

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

print(response.text)
const options = {
  method: 'POST',
  headers: {'x-api-key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    message: '<string>',
    avatar_id: '<string>',
    voice_id: '<string>',
    brand_kit_id: '<string>',
    files: [{type: '<string>', url: '<string>'}]
  })
};

fetch('https://api.heygen.com/v3/video-agents/{session_id}', 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.heygen.com/v3/video-agents/{session_id}",
  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([
    'message' => '<string>',
    'avatar_id' => '<string>',
    'voice_id' => '<string>',
    'brand_kit_id' => '<string>',
    'files' => [
        [
                'type' => '<string>',
                'url' => '<string>'
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "x-api-key: <api-key>"
  ],
]);

$response = curl_exec($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.heygen.com/v3/video-agents/{session_id}"

	payload := strings.NewReader("{\n  \"message\": \"<string>\",\n  \"avatar_id\": \"<string>\",\n  \"voice_id\": \"<string>\",\n  \"brand_kit_id\": \"<string>\",\n  \"files\": [\n    {\n      \"type\": \"<string>\",\n      \"url\": \"<string>\"\n    }\n  ]\n}")

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

	req.Header.Add("x-api-key", "<api-key>")
	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.heygen.com/v3/video-agents/{session_id}")
  .header("x-api-key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"message\": \"<string>\",\n  \"avatar_id\": \"<string>\",\n  \"voice_id\": \"<string>\",\n  \"brand_kit_id\": \"<string>\",\n  \"files\": [\n    {\n      \"type\": \"<string>\",\n      \"url\": \"<string>\"\n    }\n  ]\n}")
  .asString();
require 'uri'
require 'net/http'

url = URI("https://api.heygen.com/v3/video-agents/{session_id}")

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

request = Net::HTTP::Post.new(url)
request["x-api-key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"message\": \"<string>\",\n  \"avatar_id\": \"<string>\",\n  \"voice_id\": \"<string>\",\n  \"brand_kit_id\": \"<string>\",\n  \"files\": [\n    {\n      \"type\": \"<string>\",\n      \"url\": \"<string>\"\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body
{
  "data": {
    "session_id": "<string>",
    "run_id": "<string>",
    "title": "<string>"
  }
}
{
  "error": {
    "code": "invalid_parameter",
    "message": "'message' is required.",
    "param": "message",
    "doc_url": null
  }
}
{
  "error": {
    "code": "authentication_failed",
    "message": "Invalid or expired API key. Verify your x-api-key header.",
    "param": null,
    "doc_url": null
  }
}
{
  "error": {
    "code": "not_found",
    "message": "Session not found.",
    "param": null,
    "doc_url": null
  }
}
{
  "error": {
    "code": "rate_limit_exceeded",
    "message": "Too many requests. Retry after the duration specified in the Retry-After header.",
    "param": null,
    "doc_url": null
  }
}

Authorizations

​
x-api-key
string
header
required

HeyGen API key. Obtain from your HeyGen dashboard.

Path Parameters

​
session_id
string
required

Session ID

Body

application/json

Request body for sending a follow-up message, answering the agent's question, or requesting edits and revisions to a previously generated video.

​
message
string
required

Text message to the agent

Required string length: 1 - 10000
​
avatar_id
string | null

Override avatar for this message

​
voice_id
string | null

Override voice for this message

​
brand_kit_id
string | null

Brand kit ID to apply for this message

​
files
(AssetUrl · object | AssetId · object | AssetBase64 · object)[] | null

Optional file attachments (max 20 files)

Maximum array length: 20

Asset input via publicly accessible HTTPS URL.

Response

Successful response

​
data
SendMessageResponse · object

Response from sending a message to a session.