Smallest AI Waves Realtime TTS (WebSocket)

asyncapi: 2.6.0
info:
  title: Smallest AI Waves Realtime TTS (WebSocket)
  version: '1.0'
  description: >-
    Realtime, bidirectional text-to-speech over WebSocket for the Smallest AI
    Waves Lightning v2 model. The client opens a WebSocket connection, sends one
    or more JSON text payloads, and the server streams synthesized audio back as
    base64-encoded chunks, followed by a completion message. This is a true
    WebSocket (wss) transport - distinct from the HTTP Server-Sent Events stream
    documented on the same path in the OpenAPI definition.
  contact:
    name: Smallest AI Support
    url: https://smallest.ai/
    email: support@smallest.ai
  x-transport-notes: >-
    Transport is WebSocket (wss). Authentication is via a Bearer API key sent in
    the Authorization header on the connection handshake. The client sends JSON
    synthesis requests; the server replies with JSON frames carrying base64 audio
    chunks and a final completion frame.
servers:
  production:
    url: waves-api.smallest.ai/api/v1
    protocol: wss
    description: Waves realtime TTS WebSocket endpoint.
    security:
      - bearerAuth: []
defaultContentType: application/json
channels:
  /lightning-v2/get_speech/stream:
    description: >-
      Bidirectional channel for realtime speech synthesis. The client publishes
      synthesis requests and subscribes to streamed audio chunks and a completion
      message.
    publish:
      operationId: sendSynthesisRequest
      summary: Send text to synthesize.
      message:
        $ref: '#/components/messages/SynthesisRequest'
    subscribe:
      operationId: receiveAudio
      summary: Receive streamed audio chunks and completion.
      message:
        oneOf:
          - $ref: '#/components/messages/AudioChunk'
          - $ref: '#/components/messages/StreamComplete'
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: Waves API key passed as a Bearer token on the WebSocket handshake.
  messages:
    SynthesisRequest:
      name: synthesisRequest
      title: Synthesis Request
      contentType: application/json
      summary: A chunk of text to synthesize into speech.
      payload:
        $ref: '#/components/schemas/SynthesisRequest'
    AudioChunk:
      name: audioChunk
      title: Audio Chunk
      contentType: application/json
      summary: A base64-encoded audio chunk produced for the submitted text.
      payload:
        $ref: '#/components/schemas/AudioChunk'
    StreamComplete:
      name: streamComplete
      title: Stream Complete
      contentType: application/json
      summary: Signals that all audio for the request has been delivered.
      payload:
        $ref: '#/components/schemas/StreamComplete'
  schemas:
    SynthesisRequest:
      type: object
      required:
        - text
        - voice_id
      properties:
        text:
          type: string
          description: The text to convert to speech.
          example: Modern problems require modern solutions.
        voice_id:
          type: string
          description: Identifier of the voice to synthesize with.
          example: meher
        model:
          type: string
          description: The Lightning streaming model pool.
          default: lightning-v2
        sample_rate:
          type: integer
          description: Output audio sample rate in Hz.
          default: 24000
        speed:
          type: number
          format: float
          description: Speech rate multiplier; 1.0 is normal speed.
          default: 1.0
        language:
          type: string
          description: Language code for synthesis.
          default: en
    AudioChunk:
      type: object
      description: A streamed segment of synthesized audio.
      properties:
        audio:
          type: string
          format: byte
          description: Base64-encoded raw PCM audio chunk.
        status:
          type: string
          description: Per-chunk status indicator, when present.
    StreamComplete:
      type: object
      description: Terminal message indicating the stream has finished.
      properties:
        status:
          type: string
          example: complete
        done:
          type: boolean
          example: true