> ## Documentation Index
> Fetch the complete documentation index at: https://heygen-1fa696a7.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Cancel Avatar Realtime Session

> Cancel a running streaming session. Idempotent: `cancelled` is true when this request initiated the cancellation, or false when the session was already terminal (completed, failed, or previously cancelled).



## OpenAPI

````yaml /openapi/external-api.json post /v3/avatar-realtime/{stream_id}/cancel
openapi: 3.1.0
info:
  title: HeyGen External API
  version: 1.0.0
  description: >-
    HeyGen's external API for programmatic AI video creation. See
    https://docs.heygen.com for full documentation.
  contact:
    name: HeyGen Product Infra
    url: https://heygen.com
servers:
  - url: https://api.heygen.com
    description: Production
security:
  - ApiKeyAuth: []
  - BearerAuth: []
tags:
  - name: Video Agent
    description: Create videos from text prompts using AI
  - name: Videos
    description: Create, list, retrieve, and delete videos
  - name: Voices
    description: Text-to-speech and voice management
  - name: Audio
    description: Search the background-music and sound-effects catalog
  - name: Video Translate
    description: Translate videos into other languages
  - name: User
    description: Account information and billing
  - name: Avatars
    description: List and manage avatars and looks
  - name: Avatar Realtime
    description: >-
      Low-latency streaming avatar sessions — create a stream, poll for its HLS
      URL, push text, consume per-word timestamps
  - name: Assets
    description: Upload files for use in video creation
  - name: Webhooks
    description: Manage webhook endpoints and events
  - name: Lipsync
    description: Dub or replace audio on existing videos
  - name: Brand
    description: >-
      Brand-related resources — brand kits (colors, fonts, logos) and brand
      glossaries (custom term translations)
  - name: HyperFrames
    description: Render HyperFrames composition zips into video — separate from /v3/videos
  - name: AI Clipping
    description: Turn long-form videos into ready-to-share short clips with captions
paths:
  /v3/avatar-realtime/{stream_id}/cancel:
    post:
      tags:
        - Avatar Realtime
      summary: Cancel Avatar Realtime Session
      description: >-
        Cancel a running streaming session. Idempotent: `cancelled` is true when
        this request initiated the cancellation, or false when the session was
        already terminal (completed, failed, or previously cancelled).
      operationId: cancelAvatarRealtimeSession
      parameters:
        - name: stream_id
          in: path
          required: true
          schema:
            type: string
          description: Streaming session identifier returned by POST /v3/avatar-realtime.
      responses:
        '202':
          description: Accepted — submission acknowledged; poll for completion.
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    $ref: '#/components/schemas/CancelAvatarRealtimeResponse'
        '400':
          description: Invalid request parameters
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    $ref: '#/components/schemas/StandardAPIError'
        '401':
          description: Authentication failed
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    $ref: '#/components/schemas/StandardAPIError'
              example:
                error:
                  code: authentication_failed
                  message: Invalid or expired API key. Verify your x-api-key header.
                  param: null
                  doc_url: null
        '404':
          description: Resource not found
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    $ref: '#/components/schemas/StandardAPIError'
              example:
                error:
                  code: not_found
                  message: Streaming session not found.
                  param: null
                  doc_url: null
        '429':
          description: Rate limit exceeded
          content:
            application/json:
              schema:
                type: object
                properties:
                  error:
                    $ref: '#/components/schemas/StandardAPIError'
              example:
                error:
                  code: rate_limit_exceeded
                  message: >-
                    Too many requests. Retry after the duration specified in the
                    Retry-After header.
                  param: null
                  doc_url: null
          headers:
            Retry-After:
              description: Seconds to wait before retrying
              schema:
                type: integer
      security:
        - ApiKeyAuth: []
        - BearerAuth: []
components:
  schemas:
    CancelAvatarRealtimeResponse:
      description: Response data for POST /v3/avatar-realtime/{stream_id}/cancel.
      properties:
        stream_id:
          description: Streaming session identifier.
          title: Stream Id
          type: string
        cancelled:
          description: >-
            True if cancellation was initiated by this request, false if the
            session was already terminal (completed, failed, or previously
            cancelled).
          title: Cancelled
          type: boolean
      required:
        - stream_id
        - cancelled
      title: CancelAvatarRealtimeResponse
      type: object
    StandardAPIError:
      type: object
      properties:
        code:
          type: string
          description: Machine-readable error code
          example: invalid_parameter
        message:
          type: string
          description: Human-readable error message
          example: Video not found
        param:
          type:
            - string
            - 'null'
          description: Which request field caused the error
        doc_url:
          type:
            - string
            - 'null'
          description: Link to error documentation
      required:
        - code
        - message
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: x-api-key
      description: HeyGen API key. Obtain from your HeyGen dashboard.
    BearerAuth:
      type: http
      scheme: bearer
      description: OAuth2 bearer token.

````