TwelveLabs Analyze Streaming (HTTP + NDJSON)

asyncapi: '2.6.0'
id: 'urn:com:twelvelabs:v1.3:analyze:ndjson'
info:
  title: TwelveLabs Analyze Streaming (HTTP + NDJSON)
  version: '1.0.0'
  description: |
    AsyncAPI 2.6 description of TwelveLabs' **analyze (text generation)
    streaming** surface.

    TwelveLabs does not publish a WebSocket API. The only asynchronous /
    event-style transport documented for text generation at
    https://docs.twelvelabs.io/v1.3/api-reference/analyze-videos/analyze is
    **HTTP streaming delivered as newline-delimited JSON (NDJSON)** over the
    same REST endpoint (`POST /analyze`) when the request body sets
    `stream: true` (the default). Each newline-delimited JSON object is one
    event with an `event_type` of `stream_start`, `text_generation`, or
    `stream_end`. NDJSON is a one-way, server-to-client HTTP streaming channel;
    it is **not** WebSocket and it is **not** the `text/event-stream`
    Server-Sent Events framing.

    This AsyncAPI document models only the streamed events emitted by
    TwelveLabs' `/analyze` NDJSON response. The request body itself (video_id,
    prompt, temperature, etc.) is modeled in the companion OpenAPI document at
    `openapi/twelvelabs-openapi.yml`.

    Search, indexing, and embedding results are returned either synchronously
    or via polled task status and are therefore not modeled here.
  contact:
    name: API Evangelist
    email: kin@apievangelist.com
    url: https://apievangelist.com
  license:
    name: API documentation - TwelveLabs Terms of Use
    url: https://www.twelvelabs.io/terms-of-use
  x-transport-notes:
    transport: HTTP newline-delimited JSON (NDJSON)
    protocol: https
    direction: server-to-client (one-way)
    mediaType: application/x-ndjson
    triggeredBy: 'POST https://api.twelvelabs.io/v1.3/analyze with request body { "stream": true }'
    terminator: 'event with "event_type": "stream_end"'
    notWebSocket: true
    notServerSentEvents: true
    source: https://docs.twelvelabs.io/v1.3/api-reference/analyze-videos/analyze
defaultContentType: application/x-ndjson
servers:
  twelvelabs:
    url: api.twelvelabs.io/v1.3
    protocol: https
    description: |
      TwelveLabs REST base. Analyze (text generation) streaming is delivered
      as HTTP newline-delimited JSON over this base when `stream: true` is set
      on the JSON request body. AsyncAPI 2.6 does not define a dedicated NDJSON
      protocol identifier; `https` is used here and the NDJSON transport is
      documented in `info.x-transport-notes` and on the channel.
    security:
      - apiKeyAuth: []
channels:
  /analyze:
    description: |
      Analyze NDJSON stream. The client opens this channel by issuing
      `POST /analyze` with `Content-Type: application/json` and a JSON body
      containing `stream: true` (the default). The server responds with
      `Content-Type: application/x-ndjson` and emits a sequence of
      newline-delimited JSON objects: a single `stream_start`, one or more
      `text_generation` events each carrying a slice of generated text, and a
      final `stream_end` event carrying the finish reason and usage metadata.
    bindings:
      http:
        type: request
        method: POST
        bindingVersion: '0.3.0'
      x-ndjson:
        mediaType: application/x-ndjson
        framing: newline-delimited
        terminator: '{"event_type":"stream_end"}'
    subscribe:
      operationId: streamAnalyzeEvents
      summary: Subscribe to streamed analyze events (NDJSON).
      description: |
        After `POST /analyze` is issued with `stream: true`, the server emits
        an ordered sequence of newline-delimited JSON events. Each line is one
        JSON object whose `event_type` is `stream_start`, `text_generation`, or
        `stream_end`.
      bindings:
        http:
          type: response
          bindingVersion: '0.3.0'
      message:
        oneOf:
          - $ref: '#/components/messages/StreamStart'
          - $ref: '#/components/messages/TextGeneration'
          - $ref: '#/components/messages/StreamEnd'
components:
  securitySchemes:
    apiKeyAuth:
      type: httpApiKey
      in: header
      name: x-api-key
      description: |
        TwelveLabs API key. Set the `x-api-key: <TL_API_KEY>` header on the
        `POST /analyze` request that opens the NDJSON stream.
  messages:
    StreamStart:
      name: StreamStart
      title: Stream start event
      summary: First NDJSON event, signaling the beginning of the generation stream.
      contentType: application/x-ndjson
      payload:
        $ref: '#/components/schemas/StreamStartEvent'
      examples:
        - name: start
          summary: Stream start
          payload:
            event_type: stream_start
            metadata:
              generation_id: gen_abc123
    TextGeneration:
      name: TextGeneration
      title: Text generation event
      summary: Carries a slice of generated text. Many of these are emitted in order.
      contentType: application/x-ndjson
      payload:
        $ref: '#/components/schemas/TextGenerationEvent'
      examples:
        - name: token
          summary: Text slice
          payload:
            event_type: text_generation
            text: 'The video opens with'
    StreamEnd:
      name: StreamEnd
      title: Stream end event
      summary: Final NDJSON event, carrying finish reason and usage statistics.
      contentType: application/x-ndjson
      payload:
        $ref: '#/components/schemas/StreamEndEvent'
      examples:
        - name: end
          summary: Stream end
          payload:
            event_type: stream_end
            finish_reason: stop
            metadata:
              generation_id: gen_abc123
              usage:
                output_tokens: 256
  schemas:
    StreamStartEvent:
      type: object
      required:
        - event_type
      properties:
        event_type:
          type: string
          enum:
            - stream_start
        metadata:
          type: object
          properties:
            generation_id:
              type: string
    TextGenerationEvent:
      type: object
      required:
        - event_type
        - text
      properties:
        event_type:
          type: string
          enum:
            - text_generation
        text:
          type: string
          description: A slice of the generated text. Concatenate across events in order.
    StreamEndEvent:
      type: object
      required:
        - event_type
      properties:
        event_type:
          type: string
          enum:
            - stream_end
        finish_reason:
          type: string
          description: Reason generation stopped (e.g. stop, length).
        metadata:
          type: object
          properties:
            generation_id:
              type: string
            usage:
              type: object
              properties:
                output_tokens:
                  type: integer
                input_tokens:
                  type: integer