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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.