asyncapi: 3.0.0 info: title: SLNG Gateway API - Soniox TTS version: 0.1.0 description: Real-time text-to-speech with streaming WebSocket and one-shot HTTP synthesis contact: name: SLNG Support url: https://slng.ai email: support@slng.ai license: name: Proprietary tags: [] servers: production: host: api.slng.ai protocol: wss description: Production security: - $ref: "#/components/securitySchemes/bearer" staging: host: stageapi.slng.ai protocol: wss description: Staging security: - $ref: "#/components/securitySchemes/bearer" channels: /v1/tts/soniox/tts-rt:v1: address: /v1/tts/soniox/tts-rt:v1 title: Soniox TTS v1 summary: Real-time text-to-speech with streaming WebSocket and one-shot HTTP synthesis description: Stream real-time speech synthesis from Soniox TTS v1 over WebSocket with low-latency incremental audio output and SLNG's unified TTS protocol. tags: - name: Soniox TTS v1 servers: - $ref: "#/servers/production" - $ref: "#/servers/staging" messages: SonioxTtsRtV1Config: $ref: "#/components/messages/SonioxTtsRtV1Config" SonioxTtsRtV1TextStreaming: $ref: "#/components/messages/SonioxTtsRtV1TextStreaming" SonioxTtsRtV1Cancel: $ref: "#/components/messages/SonioxTtsRtV1Cancel" SonioxTtsRtV1AudioChunk: $ref: "#/components/messages/SonioxTtsRtV1AudioChunk" SonioxTtsRtV1Terminated: $ref: "#/components/messages/SonioxTtsRtV1Terminated" SonioxTtsRtV1Error: $ref: "#/components/messages/SonioxTtsRtV1Error" bindings: ws: method: GET headers: $ref: "#/components/schemas/WebsocketHeadersSoniox" operations: ttsSonioxTtsRtV1ReceiveConfig: action: receive channel: $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1" summary: Initialize a TTS stream description: Send a Connection Config Message to initialize a TTS stream. Sent once per stream_id before any text frames. messages: - $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1/messages/SonioxTtsRtV1Config" tags: [] ttsSonioxTtsRtV1ReceiveTextStreaming: action: receive channel: $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1" summary: Stream text to synthesize description: Send a Text Streaming Message to feed text incrementally to the active stream. Set text_end true on the final chunk. messages: - $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1/messages/SonioxTtsRtV1TextStreaming" tags: [] ttsSonioxTtsRtV1ReceiveCancel: action: receive channel: $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1" summary: Cancel an in-flight stream description: Send a Cancel Message. Server stops audio and terminates the stream. messages: - $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1/messages/SonioxTtsRtV1Cancel" tags: [] ttsSonioxTtsRtV1SendAudioChunk: action: send channel: $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1" summary: Receive synthesized audio chunks description: Receive an Audio Response. Server streams audio chunks; audio_end: true marks the final audio payload (stream not yet terminated). messages: - $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1/messages/SonioxTtsRtV1AudioChunk" tags: [] ttsSonioxTtsRtV1SendTerminated: action: send channel: $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1" summary: Receive stream termination event description: Receive a Terminal Stream Event. Server has fully closed the stream and released resources. stream_id may now be reused. messages: - $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1/messages/SonioxTtsRtV1Terminated" tags: [] ttsSonioxTtsRtV1SendError: action: send channel: $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1" summary: Receive stream error description: Receive an Error Response. After an error the stream is typically terminated (a Terminal Stream Event will follow). messages: - $ref: "#/channels/~1v1~1tts~1soniox~1tts-rt:v1/messages/SonioxTtsRtV1Error" tags: [] components: securitySchemes: bearer: type: http scheme: bearer schemas: WebsocketHeadersSoniox: type: object properties: X-World-Part-Override: type: string description: Override target world part. Auto-selected if not provided. enum: - na messages: SonioxTtsRtV1Config: name: SonioxTtsRtV1Config title: Connection Config Message summary: Initialize a TTS stream. Sent once per stream_id before any text frames. contentType: application/json payload: type: object description: Initialize a TTS stream. Sent once per stream_id before any text frames. required: - type - stream_id - model - language - voice - audio_format properties: type: type: string const: init description: Message type discriminator. Always `init` for the connection config message. api_key: type: string description: Soniox API key or temporary API key. Created in Soniox Console. Optional on gateway routes — when provided it is ignored; upstream auth is injected by the gateway. stream_id: type: string description: Client-generated unique stream identifier. Must be unique among active streams on the same connection. Can be reused only after the previous stream is terminated. model: type: string default: tts-rt-v1 description: TTS model to use. Example, `tts-rt-v1`. language: type: string default: en description: ISO 639-1 language code. Example, `en`. enum: - af - sq - ar - az - eu - be - bn - bs - bg - ca - zh - hr - cs - da - nl - en - et - fi - fr - gl - de - el - gu - he - hi - hu - id - it - ja - kn - kk - ko - lv - lt - mk - ms - ml - mr - no - fa - pl - pt - pa - ro - ru - sr - sk - sl - es - sw - sv - tl - ta - te - th - tr - uk - ur - vi - cy voice: type: string description: Voice name. Example, `Adrian`. audio_format: type: string enum: - wav - mp3 - pcm_s16le - pcm_s16be description: Output audio format. Example, `wav`. sample_rate: type: integer description: Output sample rate in Hz. Example, `24000`. bitrate: type: integer description: Codec bitrate in bps. Only applicable to lossy compressed formats. Example, `128000`. examples: - name: configExample summary: Initialize a stream with default English voice payload: type: init stream_id: stream-1 model: tts-rt-v1 language: en voice: Adrian audio_format: wav sample_rate: 24000 SonioxTtsRtV1TextStreaming: name: SonioxTtsRtV1TextStreaming title: Text Streaming Message summary: Stream text incrementally to the active stream. Set text_end true on the final chunk. contentType: application/json payload: type: object description: Stream text incrementally to the active stream. Set text_end true on the final chunk. required: - type - stream_id - text - text_end properties: type: type: string const: text description: Message type discriminator. Always `text` for streaming text chunks. stream_id: type: string description: Must match the stream_id used in the connection config message. text: type: string description: Text chunk to synthesize. Send incrementally as text is generated. text_end: type: boolean description: Set to true on the final text chunk to signal end of input. False for intermediate chunks. examples: - name: textStreamingChunk summary: Send an intermediate text chunk payload: type: text stream_id: stream-1 text: Hello from Soniox text-to-speech. text_end: false - name: textStreamingFinal summary: Send the final text chunk and close input payload: type: text stream_id: stream-1 text: Goodbye. text_end: true SonioxTtsRtV1Cancel: name: SonioxTtsRtV1Cancel title: Cancel Message summary: Cancel an in-flight stream. Server stops audio and terminates the stream. contentType: application/json payload: type: object description: Cancel an in-flight stream. Server stops audio and terminates the stream. required: - type - stream_id - cancel properties: type: type: string const: clear description: Message type discriminator. Always `clear` for the cancel message. stream_id: type: string description: Stream to cancel. cancel: const: true description: Must be `true` to trigger cancellation. Server will not send further audio and will terminate the stream. examples: - name: cancelExample summary: Cancel an active stream payload: type: clear stream_id: stream-1 cancel: true SonioxTtsRtV1AudioChunk: name: SonioxTtsRtV1AudioChunk title: Audio Response summary: Audio bytes for the stream chunk. audio_end true marks the final audio payload (stream not yet terminated). contentType: application/json payload: type: object description: Audio bytes for the stream chunk. audio_end true marks the final audio payload (stream not yet terminated). required: - type - audio - audio_end - stream_id properties: type: type: string const: audio_chunk description: Message type discriminator. Always `audio_chunk` for audio response messages. audio: type: string format: base64 description: Base64-encoded audio bytes for the stream chunk. audio_end: type: boolean description: True on the final audio chunk. No further audio payloads will follow, but the stream is not fully closed until a Terminal Stream Event arrives with terminated: true. stream_id: type: string description: Identifies which stream this audio belongs to. examples: - name: audioChunkInterim summary: An intermediate audio chunk payload: type: audio_chunk audio: UklGRiQAAABXQVZFZm10IBAAAAABAAEAQB8AAEAfAAABAAgAZGF0YQAAAAA= audio_end: false stream_id: stream-1 - name: audioChunkFinal summary: The final audio chunk for the stream payload: type: audio_chunk audio: UklGRiQAAABXQVZFZm10IBAAAAABAAEAQB8AAEAfAAABAAgAZGF0YQAAAAA= audio_end: true stream_id: stream-1 SonioxTtsRtV1Terminated: name: SonioxTtsRtV1Terminated title: Terminal Stream Event summary: Server has fully closed the stream and released resources. stream_id may now be reused. contentType: application/json payload: type: object description: Server has fully closed the stream and released resources. stream_id may now be reused. required: - type - terminated - stream_id properties: type: type: string const: terminated description: Message type discriminator. Always `terminated` for the terminal stream event. terminated: const: true description: True signals the server has fully closed the stream and released resources. Safe to reuse stream_id only after this event. stream_id: type: string description: Stream this termination event applies to. examples: - name: terminatedExample summary: Stream fully terminated payload: type: terminated terminated: true stream_id: stream-1 SonioxTtsRtV1Error: name: SonioxTtsRtV1Error title: Error Response summary: An error encountered on the stream. After an error the stream is typically terminated. contentType: application/json payload: type: object description: An error encountered on the stream. After an error the stream is typically terminated. required: - type - error_code - error_message - stream_id properties: type: type: string const: error description: Message type discriminator. Always `error` for error responses. error_code: type: integer description: "HTTP-style error code. Common values: 400, 401, 402, 408, 429, 500, 503." error_message: type: string description: 'Human-readable error description. Example: "Missing required field: model".' stream_id: type: string description: Stream that encountered the error. examples: - name: errorExample summary: Missing required field error payload: type: error error_code: 400 error_message: "Missing required field: model" stream_id: stream-1