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POST
Send Message or Request Revision

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.