> ## Documentation Index > Fetch the complete documentation index at: https://docs.modellix.ai/llms.txt > Use this file to discover all available pages before exploring further. # CosyVoice Clone > [Core Function] CosyVoice Clone clones a speaker from a public reference audio URL and synthesizes new speech in one async request; only the final audio is returned. [Strengths] No voice enrollment management; language_hint applies to both cloning and synthesis; SSML, hot_fix, and prosody controls. [Best For] One-off cloned narration and demos where a lasting voice library is not needed. [Limitations] Do NOT use this to obtain a reusable voice library entry; the cloned voice is temporary and is not returned. Reference URL must be publicly accessible. model must be cosyvoice-v3.5-plus or cosyvoice-v3.5-flash. [Routing] Choose cosyvoice-v3.5-plus for higher speech quality; cosyvoice-v3.5-flash for lower latency. ## OpenAPI ````yaml /media-model-api/alibaba/alibaba-s2s.json post /alibaba/cosyvoice-clone openapi: 3.1.0 info: title: Alibaba CosyVoice Voice Clone API description: >- CosyVoice one-shot voice cloning and speech synthesis. Submit a public reference audio URL with text as an async task; poll GET /api/v1/tasks/{task_id} for the audio. The cloned voice is temporary and is not returned or persisted. Target TTS models: cosyvoice-v3.5-plus and cosyvoice-v3.5-flash. version: 3.0.0 contact: name: Modellix Support email: support@modellix.ai servers: - url: https://api.modellix.ai/api/v1 description: Modellix API security: - bearerAuth: [] paths: /alibaba/cosyvoice-clone: post: summary: CosyVoice Clone description: >- [Core Function] CosyVoice Clone clones a speaker from a public reference audio URL and synthesizes new speech in one async request; only the final audio is returned. [Strengths] No voice enrollment management; language_hint applies to both cloning and synthesis; SSML, hot_fix, and prosody controls. [Best For] One-off cloned narration and demos where a lasting voice library is not needed. [Limitations] Do NOT use this to obtain a reusable voice library entry; the cloned voice is temporary and is not returned. Reference URL must be publicly accessible. model must be cosyvoice-v3.5-plus or cosyvoice-v3.5-flash. [Routing] Choose cosyvoice-v3.5-plus for higher speech quality; cosyvoice-v3.5-flash for lower latency. operationId: cosyvoiceClone requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CosyVoiceCloneRequest' example: model: cosyvoice-v3.5-plus url: https://example.com/reference.wav text: There is a large garden behind my house. language_hint: en format: mp3 enable_preprocess: false responses: '200': description: >- Task submitted successfully. Poll GET /api/v1/tasks/{task_id} until the task completes; synthesized audio is returned on the task result. content: application/json: schema: $ref: '#/components/schemas/AsyncTaskResponse' example: code: 0 message: success data: status: pending task_id: task-cosyvoice-clone-001 model_id: alibaba/cosyvoice-clone get_result: method: GET url: >- https://api.modellix.ai/api/v1/tasks/task-cosyvoice-clone-001 '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '429': $ref: '#/components/responses/TooManyRequests' '500': $ref: '#/components/responses/InternalServerError' components: schemas: CosyVoiceCloneRequest: type: object required: - model - url - text description: >- One-shot voice clone + TTS request. Required: model, url, text. The cloned voice is temporary and is not returned. properties: model: $ref: '#/components/schemas/CosyVoiceEphemeralTargetModel' url: type: string description: Publicly accessible reference audio URL for cloning. minLength: 1 maxLength: 2048 example: https://example.com/reference.wav text: type: string description: >- Text to synthesize with the temporarily cloned voice. Required. Max 20,000 Unicode characters. Supports plain text and SSML (set enable_ssml to true). minLength: 1 maxLength: 20000 example: There is a large garden behind my house. language_hint: type: string description: Language hint for both cloning and synthesis. Default zh. enum: - zh - en - fr - de - ja - ko - ru - pt - th - id - vi default: zh example: en max_prompt_audio_length: type: number description: >- Max reference audio duration in seconds used for cloning (3.0–30.0). Default 10.0. minimum: 3 maximum: 30 default: 10 example: 10 enable_preprocess: type: boolean description: >- Enable noise reduction and audio enhancement before cloning. Default false. default: false example: false format: type: string description: Output audio encoding format. Default mp3. enum: - mp3 - pcm - wav - opus default: mp3 example: mp3 sample_rate: type: integer description: Output sample rate in Hz. Default 22050. enum: - 8000 - 16000 - 22050 - 24000 - 44100 - 48000 default: 22050 example: 24000 volume: type: integer description: Output volume. Default 50. Range 0–100. minimum: 0 maximum: 100 default: 50 example: 50 rate: type: number description: Speech rate multiplier. Default 1.0. Range 0.5–2.0. minimum: 0.5 maximum: 2 default: 1 example: 1 pitch: type: number description: Pitch multiplier. Default 1.0. Range 0.5–2.0. minimum: 0.5 maximum: 2 default: 1 example: 1 bit_rate: type: integer description: >- Audio bit rate in kbps. Optional. Range 6–510. Only supported when format is opus; do not send for mp3, pcm, or wav. minimum: 6 maximum: 510 example: 32 instruction: type: string description: >- Optional speaking-style instruction. Weighted length ≤100 (CJK ideographs count as 2). example: Speak in a friendly customer-service tone. seed: type: integer description: Random seed. Default 0. Range 0–65535. minimum: 0 maximum: 65535 default: 0 example: 0 enable_ssml: type: boolean description: >- Whether to parse text as SSML. Default false. When true, text must follow Alibaba CosyVoice SSML rules. default: false example: false hot_fix: type: object description: >- Text hot-fix before synthesis. Optional object with pronunciation (custom pinyin) and replace (text substitution) arrays, per Alibaba CosyVoice HTTP API. example: replace: - Modellix: Modelix AsyncTaskResponse: description: Response object for asynchronous task submission. type: object required: - code - message - data properties: code: type: integer description: Response code, 0 indicates success example: 0 message: type: string description: Response message example: success data: type: object required: - status - task_id - model_id description: >- Task submission details. Poll GET /api/v1/tasks/{task_id} until status is success; audio appears in result.resources. properties: status: type: string enum: - pending - processing description: Initial task status example: pending task_id: type: string description: Unique task identifier for polling example: task-cosyvoice-clone-001 model_id: type: string description: Model ID in provider/model format example: alibaba/cosyvoice-clone get_result: type: object description: >- Endpoint to query the task result. See Common API: Query Task Result. properties: method: type: string example: GET url: type: string example: >- https://api.modellix.ai/api/v1/tasks/task-cosyvoice-clone-001 CosyVoiceEphemeralTargetModel: type: string description: Target CosyVoice v3.5 TTS model used for synthesis after cloning. enum: - cosyvoice-v3.5-plus - cosyvoice-v3.5-flash ErrorResponse: type: object required: - code - message properties: code: type: integer example: 400 message: type: string example: 'Invalid parameters: model is required' responses: BadRequest: description: Invalid request parameters content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' Unauthorized: description: Unauthorized - Invalid or missing API Key content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' TooManyRequests: description: Rate limit exceeded content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' InternalServerError: description: Internal server error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: API Key description: 'Modellix API Key. Format: Bearer ' ````